Topical Nonsteroidal Anti-Inflammatory Drugs: The Importance of Drug, Delivery, and Therapeutic Outcome

Study of the stereospecificity in the biotransformation of the four isomers of loxoprofen sodium in rats by chiral HPLC

Loxoprofen sodium is a chiral drug with two chiral centers. In our previous work, we found that the elimination of its four isomers showed stereospecificity in rats, while how the stereospecific behavior occurred in vivo was unclear. To clarify this issue, each single isomer of loxoprofen sodium was prepared by a chiral semi-preparative high-performance liquid chromatography (HPLC) and then administered to rats. By analysis of each isomer in rat plasma utilizing an analytical chiral HPLC, it was discovered that the chiral inversion occurred only to its (2R)-isomers, one from (1'S,2R)- to (1'S,2S)-isomer and the other from (1'R,2R)- to (1'R,2S)-isomer. The reduction of α-substituted cyclopentanone occurred only to its (1'R)-isomers, with (1'R,2R)-isomer reduced to (2'S,1'R,2R)-trans-alcohol and (1'R,2S)- to (2'S,1'R,2S)-trans-alcohol. Interestingly, both the inversion and the reduction reaction occurred to its (1'R,2R)-isomer due to the special stereo-structure with both (2R)- and (1'R)-configuration, and conversely, neither of them occurred to its (1'S,2S)-isomer, which caused the significantly different elimination rate in vivo. These new findings were meaningful for evaluation of the safety and efficacy of chiral drugs.

Amplified Targeted Drug Delivery Independent of Target Number through Alternative Administration of Two Matched Nanoparticles

Targeting nanoparticles (NPs) based on the specific binding of ligands with molecular targets provides a promising tool for tissue-selective drug delivery. However, the number of molecular targets on the cell surface is limited, hindering the number of NPs that can bind and, thus, limiting the therapeutic outcome. Although several strategies have been developed to enhance drug delivery, such as enhancing drug loading and circulation time or increasing the enhanced permeability and retention effect of nanocarriers, none have resolved this issue. Herein, we designed a simple method for amplified and targeted drug delivery using two matched NPs. One NP was aptamer-functionalized to specifically bind to target cells, while the other was aptamer-complementary DNA-functionalized to specifically bind to aptamer-NPs. Alternate administration of the two matched NPs enables their continuous accumulation in the disease site despite their limited molecular targets. As a proof of concept, the method was tested in a breast cancer model and significantly enhanced chemotherapy of tumor cells in vitro and in vivo. The potential applications of this method in a brain injury model were also demonstrated. Overall, the study describes a method for amplified targeted drug delivery independent of the target number.

A Bibliometric Analysis of Acupuncture Therapy in the Treatment of Musculoskeletal Pain from 2003 to 2022

Background

Acupuncture therapy has been widely used in the treatment of musculoskeletal pain (MP) in many countries around the world. However, there are no bibliometric studies on acupuncture therapy for MP. Therefore, the aim of this study was to analyze the current status, frontiers and hot spots in the use of acupuncture therapy for the treatment of MP.

Methods

Literature on acupuncture therapy for MP was extracted from the Web of Science Core Collection database from 2003 to 2022. CiteSpace 6.2.R4 (64-bit) software was used to analyze the number and centrality of journals, countries, institutions, authors, references and keywords, and the functions of co-occurrence and clustering were applied to draw a visual knowledge map.

Results

Over the past 20 years, the annual journal publications have been on a steady upward trend, with 438 articles published in 143 journals, including Acupuncture in Medicine Journal published the most (28, 6.39%), JAMA-Journal of the American Medical Association was the journal with the highest impact factor (IF = 120.7003), USA dominated with the most publications (140, 31.96%) among 44 countries, and among 196 research organizations Kyung Hee University was the most prolific (19, 4.34%) and Ha, In-Hyuk was the most published author (9, 2.05%). "Acupuncture" is the most popular and highly sought after keywords. "Low back pain" is the keyword with the highest centrality.

Conclusion

This article provides the current situation of the use of acupuncture therapy in the treatment of MP in the past 20 years, and statistical analysis reveals that "low back pain", "knit osteoporosis" and "break cancer" are new research diseases related to acupuncture therapy for MP, and "myobasic trigger point" is a new research direction of acupuncture therapy for MP. Therefore, this study helps researchers grasp the research hotspots and provide certain references for in-depth research and future topic selection.

What is the most effective and safest Non-steroidal anti-inflammatory drug for treating osteoarthritis in patients with comorbidities?

INTRODUCTION

Understanding what the most effective and safe non-steroidal anti-inflammatory drug (NSAID) is for managing osteoarthritis (OA) is complicated. OA is prevalent worldwide and people living with OA commonly have multiple comorbidities. The efficacy and safety of NSAIDs in a patient are influenced by their intrinsic and extrinsic factors. Current guidelines recommend the lowest dose for the shortest duration, monitoring patients for risk factors and comorbidities but generally do not specify, which NSAID is most suitable for a patient with specific comorbidities.

AREAS COVERED

This paper looks at the mechanism of action of all NSAIDs and reviews the current literature concerning their safety in patients with and without comorbidities. Relevant publications were identified by searching PubMed and Cochrane Library using key terms. The search was conducted from inception to 18 July 2023 and included results published before 18 July 2023. The search results and their references were then manually reviewed.

EXPERT OPINION

In the paper, we determine whether the current practice of 'lowest dose for shortest duration' is in fact the best approach for prescribing NSAIDs and identify which NSAIDs are most suitable given a patient's risk factors and comorbidities. Our aim is to help guide health professionals in recommending the most suitable NSAID for each patient.

Antinociceptive and anti-inflammatory activity of DW-1021, the ionic complex of pelubiprofen and tramadol, in rodents

Although drugs such as acetaminophen, opioids, and nonsteroidal anti-inflammatory drugs (NSAIDs), are commonly used for pain management, the side effects of these drugs such as hepatotoxicity, nephrotoxicity, nausea, and vomiting, can not be neglected. Therefore, combinations of analgesics with different mechanisms raise the possibility of developing novel analgesics. Therefore, the aim of the present study was to evaluate whether DW-1021, the ionic complex of pelubiprofen (NSAID) and tramadol (opioid), has synergic antinociceptive and anti-inflammatory effects in nociceptive as well as inflammation-induced nociceptive models compared to pelubiprofen- or tramadol-only administration. Strong synergistic antinociceptive efficacy of DW-1021 was observed in the mouse writhing test and von Frey paw withdrawal threshold test in the carrageenan-induced rats. The hot plate test in mice and the Randall-Selitto mechanical paw pressure test in carrageenan-induced rats revealed that DW-1021 had a preferable effect on relieving pain to pelubiprofen, but not as much as tramadol. In the carrageenan-induced rats, DW-1021 had a more potent effect on reducing paw inflammation (paw volume, width, and thickness) via the suppression of PGE₂ production than tramadol, but less than that of pelubiprofen. Taken together, our results suggest that the administration of DW-1021, a combination of pelubiprofen and tramadol, exerted a potent effect and can be used as a potential therapeutic agent for relieving pain and inflammation.

Multidisciplinary Guidelines for the Rational Use of Topical Non-Steroidal Anti-Inflammatory Drugs for Musculoskeletal Pain (2022)

(1) Background: Topical non-steroidal anti-inflammatory drugs (NSAIDs) are one of the primary drugs for treating musculoskeletal pain. However, there are currently no evidence-based recommendations about drug selection, drug administration, drug interactions, and use in special populations or other pharmacology-related content of such medications. To this end, the Chinese Pharmaceutical Association Hospital Pharmacy Professional Committee developed multidisciplinary guidelines on using topical NSAIDs to treat musculoskeletal pain. (2) Methods: The guidelines development process followed the World Health Organization guideline development handbook, the GRADE methodology, and the statement of Reporting Items for Practice Guidelines in Healthcare. The guideline panel used the Delphi method to identify six clinical questions to be addressed in the guidelines. An independent systematic review team conducted a systematic search and integration of evidence. (3) Results: Based on the balance between the benefits and harms of an intervention, the quality of the evidence, patient preferences and values, and resource utilization, the guideline panel developed 11 recommendations and nine expert consensuses on using topical NSAIDs to treat acute and chronic musculoskeletal pain. (4) Conclusions: Based on the effectiveness and overall safety of topical NSAIDs, we recommend patients with musculoskeletal pain use topical NSAIDs and suggest high-risk patients use topical NSAIDs, such as those with other diseases or receiving other concurrent treatments. The evidenced-based guidelines on topical NSAIDs for musculoskeletal pain incorporated a pharmacist perspective. The guidelines have the potential to facilitate the rational use of topical NSAIDs. The guideline panel will monitor the relevant evidence and update the recommendations accordingly.

Nanostructured Lipid Carriers (NLC)-Based Gel Formulations as Etodolac Delivery: From Gel Preparation to Permeation Study

Topical administration of drug is an attractive alternative to the oral administration as it provides a reduction in adverse reactions and an enhancement of therapeutic effects. The use of lipid carriers in hydrogel structures makes it possible to introduce lipophilic substances in a dissolved form. In this study, an NSAID from the BCS class II, etodolac (ETD), was used. The nanostructured lipid carriers (NLC) obtained with ETD were incorporated into semi-solid forms (gels). Hydrogels with the suspended drug and oleogel were also prepared for comparison purposes. The obtained gels were tested in terms of pH, viscosity, rheological, mechanical, and bioadhesive properties. The release and permeation through membranes were also studied. All tested formulations were characterized by a pH below 7, which ensured the physiological state of the skin. The viscosities of all gels decreased with increasing shear rate, indicating non-Newtonian behavior. The fastest ETD release was observed for NLC with a Carbopol base (formulation F1); a similar result was noticed in the permeation test. The developed gel formulations containing ETD-NLC dispersion and Carbopol or Poloxamer as gelling agents were stable and possessed beneficial pharmaceutical properties.

Shea Butter Potentiates the Anti-Bacterial Activity of Fusidic Acid Incorporated into Solid Lipid Nanoparticle

Fusidic acid (FA) is an efficient anti-bacterial drug proven to be efficient against a wide range of bacteria. Nevertheless, the main restriction in its formulation is the limited solubility. To avoid such an obstacle, the drug is incorporated into the lipid core of the nanolipid formulation. Consequently, the present study was an attempt to formulate nanolipid preparation, mainly, solid lipid nanoparticle (SLN) integrating FA. FA-SLN was prepared using shea butter as a lipid phase owing to its reported anti-bacterial activity. Different FA-SLNs were fabricated using the central composite design (CCD) approach. The optimized formula was selected and integrated into a hydrogel base to be efficiently used topically. FA-SLN-hydrogel was evaluated for its character, morphology, in vitro release and stability. The formula was examined for irritation reaction and finally evaluated for its anti-bacterial performance. The optimized formula showed particle size 283.83 nm and entrapment 73.057%. The formulated FA-SLN-hydrogel displayed pH 6.2, viscosity 15,610 cP, spreadability 51.1 mm and in vitro release 64.6% following 180 min. FA-SLN-hydrogel showed good stability for three months at different conditions (room temperature and refrigerator). It exhibited no irritation reaction on the treated rats. Eventually, shea butter displayed a noteworthy effect against bacterial growth that improved the effect of FA. This would indicate prospective anti-bacterial activity of FA when combined with shea butter in SLN formulation as a promising nanocarrier.

Integrating Inflammation-Responsive Prodrug with Electrospun Nanofibers for Anti-Inflammation Application

Chronic inflammation plays a side effect on tissue regeneration, greatly inhibiting the repair or regeneration of tissues. Conventional local delivery of anti-inflammation drugs through physical encapsulation into carriers face the challenges of uncontrolled release. The construction of an inflammation-responsive prodrug to release anti-inflammation drugs depending on the occurrence of inflammation to regulate chronic inflammation is of high need. Here, we construct nanofiber-based scaffolds to regulate the inflammation response of chronic inflammation during tissue regeneration. An inflammation-sensitive prodrug is synthesized by free radical polymerization of the indomethacin-containing precursor, which is prepared by the esterification of N-(2-hydroxyethyl) acrylamide with the anti-inflammation drug indomethacin. Then, anti-inflammation scaffolds are constructed by loading the prodrug in poly(ε-caprolactone)/gelatin electrospun nanofibers. Cholesterol esterase, mimicking the inflammation environment, is adopted to catalyze the hydrolysis of the ester bonds, both in the prodrug and the nanofibers matrix, leading to the generation of indomethacin and the subsequent release to the surrounding. In contrast, only a minor amount of the drug is released from the scaffold, just based on the mechanism of hydrolysis in the absence of cholesterol esterase. Furthermore, the inflammation-responsive nanofiber scaffold can effectively inhibit the cytokines secreted from RAW264.7 macrophage cells induced by lipopolysaccharide in vitro studies, highlighting the great potential of these electrospun nanofiber scaffolds to be applied for regulating the chronic inflammation in tissue regeneration.

In Vitro Evaluation of a Foamable Microemulsion Towards an Improved Topical Delivery of Diclofenac Sodium

Topical microemulsion (ME) might provide a novel and advanced transdermal delivery system due to the enhances of drug solubility and permeability across the stratum corneum. Foams are topical delivery systems that have excellent patient compliance, acceptability, and preference. Therefore, this study aimed to investigate a foamable microemulsion as an alternative topical and transdermal dosage form for diclofenac sodium (DS). The physicochemical properties (optical clarity, percentage transmittance, homogeneity, consistency of formulation, particle size, zeta potential, conductivity, viscosity, and morphology, etc.) of the DS-loaded ME were investigated. The foam stability of both drug-free ME and DS-loaded ME was measured. The foam quality was evaluated, and the chemical stability over 90 days was determined. Franz diffusion cells were employed to assess the in vitro drug release of a foamed DS-loaded ME and compared with a commercial topical product. A foamable and stable DS-loaded ME that maintained small particle sizes and constant zeta potential and was transparent and translucent in appearance after 90 days was successfully produced. The foam of the DS-loaded ME was physically more stable compared to the drug-free foam. The foam had an increased drug release rate compared to the commercial product. The foamable DS-loaded ME has a great potential to enhance the transdermal delivery of DS after topical administration. Foamed DS-loaded ME is a promising alternative to the current topical formulation of DS.

Biosorption of ketoprofen and diclofenac by living cells of the green microalgae Chlorella sp

There is a growing interest for the removal of different pharmaceuticals from water owing to their toxicity to various organisms. The present study investigated the use of living cells of the green alga Chlorella sp. in the short-term adsorption of ketoprofen (KET) and diclofenac (DIF) from aqueous solutions. The bioremoval efficiency of both KET and DIF was highly dependent on various parameters such as time, pH, algal dosage, and drug concentration. The adsorption efficiencies of both KET and DIC were maximized at pH 6. The biosorption of KET was better described by pseudo-first-order kinetics, while DIC obeyed the pseudo-second-order model. The maximum adsorption capacities of KET and DIF were attained as 0.328 and 0.429 mg g^-1, respectively. The equilibrium data of the investigated drugs showed a better fit to the Freundlich model than the Langmuir model. The Elovich and Temkin models indicated that the algal surface was heterogeneous with different binding energies, while the intraparticle diffusion model assumed a boundary layer effect. Additionally, the Dubinin-Radushkevich isotherm indicated that the adsorption process was predominantly physisorption. FT-IR analysis revealed that H-bonding and n-π interactions were prominent in the biosorption process of the investigated pharmaceuticals on the surface of microalgae. The results of the present study showed that microalgae living cells could be applied as an eco-friendly and cost-effective biosorbent for the removal of KET and DIF at low concentrations.

Topical opioid use in dermatologic disease: A systematic review

Topical opioid formulations offer a potential solution to manage pain and decrease the use of systemic opioids. Synthesis of use and efficacy of topical opioids in dermatological conditions has not been well characterized. We conducted a systematic search of the PubMed, Embase, and Cochrane databases from 1980 to February 2021. This study analyzed data from 14 articles and 263 patients on the use of topical opioids for pain related to chronic ulcers, burns, oral lichen planus, photodynamic therapy, and split-thickness skin grafts. Topical opioids included in this review were topical morphine and diamorphine. Common formulations consisted of 0.2-10 mg of opioid compounded with hydrogel or IntraSite gel. Topical opioids were variably effective in the use for pain control related to chronic ulcers and other dermatologic conditions. For example, the use of topical opioids appears to be effective in the reduction of pain related to pressure ulcers. Topical opioids were generally well tolerated. Insufficient data exist to adequately evaluate the efficacy and safety of topical opioid use in the context of nonpressure ulcers, burns, oral lichen planus, photodynamic therapy, and split-thickness skin grafts.

Enantioselective separation of nonsteroidal anti-inflammatory drugs with amylose tris(3-chloro-5-methylphenylcarbamate) stationary phase in HPLC with a focus on enantiomeric quality control in six pharmaceutical formulations containing racemic mixtures or single stereoisomers

In the present study, an accurate, rapid, and simple chiral HPLC-UV method with amylose tris(3-chloro-5-methylphenylcarbamate) as stationary phase was developed and applied for enantiomeric determination of six nonsteroidal anti-inflammatory drugs (NSAIDs) in the commercial pharmaceutical formulations, including (R,S)-ibuprofen, S-ibuprofen, (R,S)-ketoprofen, S-ketoprofen, S-naproxen, and (R,S)-loxoprofen sodium. Experiments on the influence of mobile phase composition, proportion of organic modifier, percentage of acid additives, and column temperature on enantioseparation were conducted to obtain the best separation condition. It was indicated that one mobile phase simply composed of acetonitrile-water (0.1% formic acid, v/v) at the proportion of 50:50 (v/v) with a flow rate of 0.6 ml/min at 22°C could simultaneously provide the excellent enantiomeric resolutions for all selected NSAIDs, which made the enantioseparation process more applicable and operable. The newly developed method was then applied for determination of NSAID enantiomers in pharmaceutical formulations containing racemic mixtures or single stereoisomers. Calibration curve of each enantiomer at the concentration of 5.0-100 ug/ml showed good linearity with the correlation coefficient above 0.9996. Satisfactory recovery (96.54-101.54%), good intra-day precision (RSD 0.52-1.46%), and inter-day precision (RSD 0.13-1.09%) were also obtained. The newly developed method was then applied for determination of NSAID enantiomers in pharmaceutical formulations containing racemic mixtures or single stereoisomers. Quantitative results of the commercial capsules and tablets demonstrated that the difference between the declared and measured values did not exceed 1.52%.

Polyhydroxyalkanoates, bacterially synthesized polymers, as a source of chemical compounds for the synthesis of advanced materials and bioactive molecules

Research into polyhydroxyalkanoates (PHAs) is growing exponentially. These bacterially derived polyesters offer a spectrum of possible applications, such as in manufacturing of daily-use objects, production of medical devices and implantable objects, or as synthons in chemical and pharmaceutical industries. Thanks to their broad physicochemical features, PHAs can be seen as polymers of the future, which can replace traditional petrochemical equivalents. As they are synthesized by bacteria through fermentation processes, these polyesters can be obtained from virtually any carbon source in a sustainable manner. Characterized by biodegradability and biocompatibility, they are used in many industries, ranging from production of everyday objects to medical applications. Furthermore, as they are built from bioactive monomers, namely (R)-3-hydroxyacids, they provide a platform for the synthesis of advanced chemical compounds. In this mini review, the reader will be acquainted with recent studies conducted at the Jerzy Haber Institute of Catalysis and Surface Chemistry of the Polish Academy of Sciences in collaboration with other groups that have contributed to the development of PHA-based medical materials, bioactive molecules and novel green solvents derived from PHA monomers.Key points• Polyhydroxyalkanoates are emerging polymers for biomedical applications• Polyhydroxyalkanoates can be modified easily to provide novel materials• (R)-3-Hydroxyacids are good synthons for bioactive substances and green solvents.

Topical NSAIDs for acute local pain relief: in vitro characterization of drug delivery profiles into and through human skin

OBJECTIVE

The efficacy of topical nonsteroidal anti-inflammatory drugs (NSAIDs) relates not only to the individual NSAID used but also to differences in formulation design. The aim of this study was to investigate the fundamental differences in ibuprofen and diclofenac drug delivery vehicles, specifically gels and plasters, compared to a recently launched 200 mg ibuprofen medicated plaster and characterize the resulting dermatologic-pharmacokinetic profiles into and through ex vivo human skin layers.

METHODS

In vitro skin permeation testing over 24 h and sacrificial timepoint penetration experiments (at 1, 4, 8, 12, and 24 h) were conducted using an automated flow-through diffusion cell system. The amount of drug delivered to the epidermis, dermis, and receptor solution (representing deeper tissue) was determined by liquid chromatography-tandem mass spectrometry. Skin protein binding of ibuprofen and diclofenac was investigated by spiking skin homogenate with increasing concentrations of each drug and determining the fraction unbound.

RESULTS

Differences were observed in the amount of drug recovered at sacrificial timepoints and rate at which drug was delivered to the target site between plaster and gel formulations of ibuprofen and diclofenac and between plaster formulations of the same drug (ibuprofen). While the amount of drug quantified at sacrificial timepoints did not necessarily determine in vivo flux rates, differences in drug distribution within the skin layers indicated where drug reservoirs were formed.

CONCLUSIONS

These findings highlight the importance of intelligent formulation design in determining NSAID delivery through skin layers. Further work is required to quantify drug delivery into deeper tissues and the resultant local anti-inflammatory effects.

Effect and usability of anti-inflammatory drug plasters for knee osteoarthritis: A crossover, double-blind, repeated measures, randomized controlled trial

BACKGROUND

The use of plasters is a well-accepted treatment with high adherence. However, the characteristics such as its cool feeling or extensibility favored by elderly have a possibility to contribute to clinical utility. The purpose is to examine the effect of anti-inflammatory drug plasters for knee osteoarthritis and the clinical preference of the patients for using plasters. We conducted a crossover, double-blind, randomized controlled trial (RCT) recruited 168 patients with knee osteoarthritis.

METHODS

We included a "run-in-period" to evaluate the patients' preference among A (first-generation; methyl salicylate), B (second-generation; indomethacin), and N (base substrate for B) before the crossover sequence of two treatment periods with A and B plasters; four arms (N-A-B, A-A-B, N-B-A, and B-B-A) were made to compare the assessment of A, B, and N plasters. We used two measures: The Japanese Knee Osteoarthritis Measure (JKOM), for clinical functions, and the usability questionnaire to evaluate the clinical value of plasters.

RESULTS

At baseline, there were no significant differences in characteristics. The subjects in groups A and B showed improved overall JKOM scores at the end of each intervention. Comparison of the change of the mean difference showed that A and B were statistically significant improvement over N (-2.40, (95%CI = -3.58 to -1.21), -2.52, (-3.65 to -1.40)) but no significant difference between A and B - 0.13, (-1.14 to 0.89)). In network analysis for usability, twelve items were independent of JKOM's network structure and consisted of two domains. The analysis of usability showed that N and B were preferred over A significantly.

CONCLUSION

Both the first- and second-generation plasters were statistically superior to the base only, but no significant difference between two generations. The patient is surely aware of the effect of the drug itself, but the two feelings are important in the preference.

Self-Medicating for Pain: A Public Health Perspective

BACKGROUND

Pain is one of the symptoms for which any man is willing not only to go to the doctor but also to resort to any means, including self-medication, to "get rid" of it. Self-medication is not only a current practice but also a public health problem, under the circumstances that it can influence the way in which a disease is diagnosed and/or treated in a timely manner, and, consequently, repercussions may occur on the cost of treatment, in the case of severe forms. Pain is a vital symptom, and the diminution until the disappearance of pain is a fundamental right of each individual; the analysis of ethical issues in the case of self-administration of analgesic medication has not been a major concern.

AREAS OF UNCERTAINTY

Understanding the problem is important to realize whether self-medicating for pain is a necessity or an abuse, and in this respect, we review scientific articles from international databases: PubMed and ProQuest.

DATA SOURCES

The study is based on the consultation of scientific articles from international databases-PubMed and ProQuest, the main keywords in the search being pain and self-medication, to which a stigma or public health is sequentially added.

RESULTS

Pain is becoming more and more a global problem and the extent of its spread can substantiate our assertion about pathology with pandemic impact. Under the pressure of patient associations, of the media, and of nonmedical authorities, the opinion about the need for a stoic approach to pain has long become an outdated theory, and chronic pain, beyond a multidimensional approach, is increasingly considered not only a useless element but also even a destructive one.

CONCLUSIONS

Pain and self-medication must be addressed, including in medical practice, starting from their multidimensionality from the following perspectives: medicobiological, sociocultural, instructive-educational, legal-political, and especially ethical. They are not only individual health problems but also become, when connected with a stigma, a public health problem.

A systematic assessment of the association between frequently prescribed medicines and the risk of common cancers: a series of nested case-control studies

BACKGROUND

Studies systematically screening medications have successfully identified prescription medicines associated with cancer risk. However, adjustment for confounding factors in these studies has been limited. We therefore investigated the association between frequently prescribed medicines and the risk of common cancers adjusting for a range of confounders.

METHODS

A series of nested case-control studies were undertaken using the Primary Care Clinical Informatics Unit Research (PCCIUR) database containing general practice (GP) records from Scotland. Cancer cases at 22 cancer sites, diagnosed between 1999 and 2011, were identified from GP records and matched with up to five controls (based on age, gender, GP practice and date of registration). Odds ratios (OR) and 95% confidence intervals (CI) comparing any versus no prescriptions for each of the most commonly prescribed medicines, identified from prescription records, were calculated using conditional logistic regression, adjusting for comorbidities. Additional analyses adjusted for smoking use. An association was considered a signal based upon the magnitude of its adjusted OR, p-value and evidence of an exposure-response relationship. Supplementary analyses were undertaken comparing 6 or more prescriptions versus less than 6 for each medicine.

RESULTS

Overall, 62,109 cases and 276,580 controls were included in the analyses and a total of 5622 medication-cancer associations were studied across the 22 cancer sites. After adjusting for comorbidities 2060 medicine-cancer associations for any prescription had adjusted ORs greater than 1.25 (or less than 0.8), 214 had a corresponding p-value less than or equal to 0.01 and 118 had evidence of an exposure-dose relationship hence meeting the criteria for a signal. Seventy-seven signals were identified after additionally adjusting for smoking. Based upon an exposure of 6 or more prescriptions, there were 118 signals after adjusting for comorbidities and 82 after additionally adjusting for smoking.

CONCLUSIONS

In this study a number of novel associations between medicine and cancer were identified which require further clinical and epidemiological investigation. The majority of medicines were not associated with an altered cancer risk and many identified signals reflected known associations between medicine and cancer.

The importance of over-the-counter-sales and product format in the environmental exposure assessment of active pharmaceutical ingredients

When assessing the environmental exposure of active pharmaceutical ingredients (APIs), the mass contributed from over the counter (OTC) sales are often not included due to difficulty obtaining this data and topical formats are overlooked completely. This study presents a comprehensive approach, investigating the significance of OTC and topical applications as sources of API releases to wastewater, in addition to temporal and subnational variations in use in the UK. The study provides methods to obtain and make use of OTC sales data which can be applied widely. The calculated releases to wastewater compared well with influent concentrations measured at several UK wastewater treatment plants (WWTPs). Consistent overestimation was observed, attributed to a number of factors, including in-sewer removal. OTC sales were found to make up a large proportion of the mass of ibuprofen (76%) and diclofenac (35%) consumed and topical formats were also found to be vital, contributing disproportionately to wastewater loadings per unit mass of ibuprofen and diclofenac used (43% and 99% of the total mass released, respectively). Releases of the APIs investigated did not vary temporally, but regional variation was significant and where possible should be considered for the most accurate exposure assessment of pharmaceuticals.

Topical capsaicin versus topical ibuprofen in acute musculoskeletal injuries: A randomized, double-blind trial

Background:

Acute musculoskeletal pain is one of the common causes of emergency admissions. Topical analgesics are an easily tolerated option in the treatment of these pains.

Objective:

This study aimed to compare the efficacy of topical capsaicin and topical non-steroidal anti-inflammatory drugs in acute musculoskeletal injuries.

Methods:

In this prospective, randomized, controlled, double-blinded study, patients were allocated to two groups—the topical non-steroidal anti-inflammatory drug (n = 60) and topical capsaicin (n = 59). For both groups, the first dose treatment was applied as a thin layer in the emergency department to a maximum area of 5 × 5 cm. The remaining doses were administered at home by the patients for 72 h. The initial visual analog scale scores were compared with the 60th and 120th minute as well as the 24th and 72nd hour values. Differences between the visual analog scale scores, clinical response to the treatment, and side effects were evaluated.

Results:

The proportional reduction in visual analog scale scores for topical capsaicin was significantly higher, especially at 36 and 72 h. These rates were 0.75 (95% confidence interval: 0.77–1.42; p = 0.029) and 9.08 (95% confidence interval: 1.02–17.14; p = 0.028) at 36 h, respectively. At 72 h, they were 1.27 (95% confidence interval: 0.48–2.05; p = 0.002) and 17.07 (95% confidence interval: 8.39–25.76; p < 0.001), respectively. In the topical capsaicin group, the clinical response to treatment was significantly higher (p = 0.001). Treatment-related systemic side effects were experienced only in the topical non-steroidal anti-inflammatory drug group (1.7%).

Conclusion:

Topical capsaicin can be used safely in patients presenting to the emergency department with acute pain with its high analgesic efficacy and absence of systemic side effects.

An ex vivo skin model to probe modulation of local cutaneous arachidonic acid inflammation pathway

There is a need for inexpensive and reliable means to determine the modulation of cutaneous inflammation. The method outlined in this article draws together a number of scientific techniques and makes use of generally unwanted biological tissues as a means of determining skin inflammation ex vivo, and focuses on probing aspects of the arachidonic acid inflammation pathway. Freshly excised skin contains elevated levels of short-lived inducible cyclooxygenase-2 (COX-2) and, under viable conditions, COX-2 and its eicosanoid products will continue to be produced until tissue necrosis, providing a window of time in which relative levels can be probed to determine exacerbation due to an upregulating factor or downregulation due the presence of an agent exerting anti-inflammatory activity. Ex vivo porcine skin, mounted in Franz diffusion cells, is dosed topically with the xenobiotic challenge and then techniques such as Western blotting and immunohistochemistry can then be used to probe relative COX-2 levels on a semi-quantitative or qualitative level. Enzyme-linked immunosorbent assay or LCMS can be used to determine relative prostaglandin E-2 (PGE-2) levels. Thus far, the technique has been used to examine the effects of topically applied anti-inflammatories (betamethasone, ibuprofen, ketoprofen and methotrexate), natural products (fish oil, Devil’s claw extract and pomegranate rind extract) and drug delivery vehicle (polyNIPAM nanogels). Topically applied xenobiotics that modulate factors such as COX-2 and PGE-2 must penetrate the intact skin, and this provides direct evidence of overcoming the "barrier function" of the stratum corneum in order to target the viable epidermis in sufficient levels to be able to elicit such effects. This system has particular potential as a pre-clinical screening tool for those working on the development of topical delivery systems, and has the additional advantage of being in line with 3 Rs philosophy.

Comparison of ibuprofen and piroxicam gel in the treatment of trauma pain: A randomized double-blind trial of geriatric population

OBJECTIVE

This study aimed to compare the analgesic efficacy of topical ibuprofen and topical piroxicam for acute musculoskeletal injuries.

METHODS

In this prospective, randomized, controlled, double-blinded study, geriatric patients were assigned to groups to receive either topical ibuprofen (n = 70) or topical piroxicam (n = 69). The first dose of gel was applied in the emergency department and the remaining doses were self-administered at home by the patients thrice daily for 72 h. For each patient, the initial baseline visual analog scale (VAS) score (V 0) was compared with the VAS scores at the 60 min (V1), 120 min (V2), 24 h (V3) and 72 h (V4) time points. The decreases in VAS scores, clinical effectiveness of the treatments, and incidence of adverse events were evaluated.

RESULTS

In the topical ibuprofen group, the VAS scores were significantly lower at each measurement time point compared to baseline (p < .001). The results were as follows: V0 -V: 1.08, 95% CI: 0.56-1.61; V0 -V2: 1.09, 95% CI: 0.49-1.69; V0 -V3: 1.44, 95% CI: 0.81-2.07; V0 -V4: 1.59, 95% CI: 0.91-2.26. The mean percentage decrease in the VAS scores in the topical ibuprofen group was significantly higher than that in the topical piroxicam group (p < .001). The clinical effect of treatment was found to be significantly higher for the ibuprofen gel group (p < .001). There was no substantial difference in treatment-related adverse events between the groups (p > .05).

CONCLUSION

Ibuprofen gel, which is a safe treatment option for geriatric patients, is more clinically effective than piroxicam gel. Response to Reviewers.

Copaiba oleoresin has topical antinociceptive activity in a UVB radiation-induced skin-burn model in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Copaiba oleoresin, extracted from Copaifera L., is used as a wound healing, analgesic, antimicrobial and, mainly, anti-inflammatory agent. Thus, in this study we investigated the antinociceptive and anti-inflammatory effects of a topical formulation containing Copaiba oleoresin (3%) in a UVB radiation-induced skin burn model (0.75 J/cm²) in mice and performed a cream-formulation stability study.

MATERIALS AND METHODS

The chemical composition of Copaiba oleoresin was analyzed using gas chromatography (GC-MS). The topical antinociceptive (evaluated through mechanical allodynia and thermal hyperalgesia) and the anti-inflammatory (dermal thickness and inflammatory cell infiltration) effects of treatments were assessed. The cream-formulation stability study was performed after two months, and organoleptic characteristics, pH, spreadability and rheological characteristics were analyzed.

RESULTS

Copaiba oleoresin cream was able to prevent UVB radiation-induced mechanical allodynia on the 2nd, 3rd and 4th day after UVB radiation exposure with a maximum inhibition (I_max) of 64.6 ± 7% observed on the 2nd day; it also reduced the thermal hyperalgesia on the 1st and 2nd days post UVB radiation, with a I_max of 100% observed on the 2nd day. Moreover, topical treatment with Copaiba oleoresin cream inhibited the inflammatory cell infiltration, but did not reduce the dermal thickness. Such effects can be attributed, at least in part, to the presence of biological components, such as β-caryophyllene and other sesquiterpenes identified by GC-MS.

CONCLUSION

Our results demonstrate that the topical formulation containing Copaiba oleoresin presented antinociceptive and anti-inflammatory effects in mice subjected to a UVB radiation and that the cream-formulation was stable for two months. Thus, use of Copaiba oleoresin is a promising strategy for the treatment of inflammatory pain associated with sunburn.

Diclofenac sodium aqueous systems at low concentrations: Interconnection between physicochemical properties and action on hydrobionts

Diclofenac sodium (DS) is a widely used nonsteroidal anti-inflammatory drug (NSAIDs). NSAIDs are poorly removed during standard wastewater treatment. The consequences of the presence of NSAIDs in rivers and lakes at 10^-11-10^-8 mol/L are not yet established; therefore, ecotoxicologists have focused their efforts on studying the effect of low-concentration NSAIDs on fish and hydrobionts, and also on predicting the potential risks to humans. Literature provides some information about the bioeffects of some NSAID solutions in low concentrations but there is no physicochemical explanation for these phenomena. Studying the physicochemical patterns of DS solutions in the low range of concentrations and establishing an interconnection between the solutions' physicochemical properties and bioeffects can provide a conceptually new and important source of information regarding the unknown effects of DS. The physicochemical properties and action of DS solutions on Ceriodaphnia affinis cladocerans, Paramecium caudatum infusoria, Chlorella vulgaris unicellular green algae, as well as on the growth of the roots of Triticum vulgare wheat seeds, were studied in the calculated concentration range of 1 × 10^-3-1 × 10^-18 mol/L. The relationship between these phenomena was established using the certified procedures for monitoring the toxicity of natural water and wastewater. It was shown for the first time that water solutions of DS are dispersed systems in which the dispersed phase undergoes a rearrangement with dilution, accompanied by changes in its size and properties, which affects the nonmonotonic dependences of the system's physicochemical properties and could cause nonmonotonic changes in action on hydrobionts in the low concentration range.

Transdermal Administration of Ibuprofen-Loaded Gel: Preparation, Pharmacokinetic Profile, and Tissue Distribution

The purpose of this study was to compare the pharmacokinetics and tissue distribution of ibuprofen (IBU) gel in female rats after transdermal administration through the skin of the abdomen and back. IBU was used as the model drug to prepare carbomer gel. After the abdominal and back administration, the concentration of IBU in rat plasma was detected by high-performance liquid chromatography (HPLC). Besides, the contents of IBU in the uterus, heart, liver, spleen, lung, and kidney were detected, respectively, to clarify the distribution characteristics in vivo. Through abdominal route, the AUC0- ∞ (area under the concentration-time curve from time zero to infinity) of uterus was 424.75 μg/g h, which is 3.60 times higher than that of plasma, and was significantly higher than that of other tissues (P < 0.0001). Tmax (peak time) of uterus and plasma was 4 h and 2 h, respectively. Upon transdermal application of IBU to the back, the AUC0-∞ of uterus was 75.47 μg/g h, which is 12.63 times lower than that of plasma, while Tmax of uterus and plasma was not lower than 20 h. These results indicated that IBU entered the blood circulation through abdominal administration in a small amount and mainly of the drug entered the uterus, while IBU entered the blood circulation and redistributed to tissues after absorption through the dorsal skin slowly. IBU could effectively reach the uterus and have a certain targeting through abdominal administration, which provides a prospect for clinical transdermal administration in the treatment of dysmenorrhea.

Efficacy and safety of loxoprofen sodium topical patch for the treatment of pain in patients with minor acute traumatic limb injuries in Brazil: a randomized, double-blind, noninferiority trial

Posttraumatic injury pain is commonly treated with oral nonsteroidal anti-inflammatory drugs. However, oral nonsteroidal anti-inflammatory drugs cause several adverse events, with topical formulations arising as an important alternative. Therefore, we aimed at evaluating the efficacy and safety of loxoprofen patch (LX-P) in the treatment of patients with posttraumatic pain. This phase III, randomized, double-blind, noninferiority study enrolled Brazilian patients aged 18 to 65 years diagnosed with lower and upper limb posttraumatic injury who were experiencing moderate or severe pain. Patients were assigned to active LX-P or to loxoprofen tablet (LX-T), and pain intensity was measured based on a visual analog scale score variation after 7 days of treatment. Data on clinical symptoms, rescue medication use, and adverse events were also collected. Visual analog scale score variation was compared using a 10% noninferiority margin. Two hundred forty-two patients were randomly assigned to LX-P (n = 123) or to LX-T (n = 119). The results showed a reduction in pain after 7 days of treatment: -49.96 (n = 118; SE 1.7) in the LX-P and -47.71 (n = 117; SE 1.6) in the LX-T groups (difference of -2.25; 95% CI: -5.97 to 1.47; P = 0.23). On the safety analysis, the LX-T group presented twice as many patients with treatment-emergent adverse events as the LX-P group (30.8% and 14.2%, respectively). A sensitivity analysis demonstrated that rescue medication use has not affected the primary end point. This study showed that LX-P has a comparable efficacy to LX-T, but with a better safety profile, being a therapeutic option for the treatment of posttraumatic injury pain.

Inhibition of platelet function after ocular administration of non-steroidal anti-inflammatory drugs

INTRODUCTION

The use of topical NSAIDs is frequent in ophthalmology to reduce the local inflammatory reaction resulting from surgical procedures. Ocular use of some drugs was previously found to lead to significant systemic absorption with possible systemic effects. NSAIDs may enhance the hemorrhagic risk of anticoagulant and antiplatelet drugs. Aim of our study was to evaluate the systemic effects of two NSAIDs given by eyedrops on platelet COX-1 and on ex vivo and in vivo platelet activation.

MATERIALS AND METHODS

20 patients planned to undergo cataract surgery were randomized to the use of an ophthalmic solution containing Diclofenac or Indomethacin. Blood was taken at enrollment (baseline) and after 3 days of therapy (1 drop, 4 times a day). Arachidonic Acid (AA)-induced light transmission aggregometry (LTA), PFA-100® C-EPI, circulating platelet P-Selectin expression by flow cytometry and serum and AA-induced TxB₂ production were evaluated before and after eyedrop therapy.

RESULTS

AA (0.1-0.2 mM)-induced LTA was significantly reduced after ocular indomethacin but not after diclofenac. PFA-100® C-EPI closure time was also significantly prolonged in the indomethacin group but not in the diclofenac group. Circulating platelet P-selectin expression was significantly reduced after treatment with indomethacin compared with diclofenac. Finally, treatment with eyedrop indomethacin, but not with diclofenac, strikingly suppressed AA-induced TxB₂ generation, while treatment with diclofenac did not modify it.

CONCLUSIONS

Our data show that indomethacin administered by ophthalmic eye drops has a relevant systemic antiplatelet effect. This should be taken into account in patients under concurrent therapy with antiplatelet or anticoagulant agents.

Ex vivo transdermal absorption of a liposome formulation of diclofenac

Topical formulations of non-steroidal anti-inflammatory drugs are often used to provide effective local drug concentration while limiting systemic exposure and associated adverse events. Formulation composition has great influence on the rate of transdermal drug transport through human skin. This study was performed to compare the ex vivo transdermal transport of diclofenac from three topical formulations, a 1% liposomal gel formulation of diclofenac sodium and two emulsion gel formulations, 1.16% and 2.32% diclofenac diethylamine (equivalent to 1% and 2% diclofenac sodium). Human skin was obtained during unrelated surgical procedures and frozen at -20 °C until use. Three skin specimens were thawed, prepared for testing, and placed in a Franz cell with the stratum corneum facing the donor compartment. About 200 μl of each formulation was placed on the skin, and the receptor compartment fluid (phosphate buffered saline, pH 7.4, 32 °C) was sampled over the next 48 h. Diclofenac concentration was measured with a validated HPLC method. The transdermal permeability coefficient for the liposome 1% gel was 69.3 ± 14.4 10^-8 cm•s^-1, compared with 34.9 ± 9.1 10^-8 cm•s^-1 (P = 0.001) and 47.1±9.5 10^-8 cm•s^-1 (P = 0.005) for the emulsion gel 1.16% and emulsion gel 2.32%, respectively. A statistically significant difference between transdermal transport of diclofenac from the liposome gel 1% and the emulsion gel 1.16% was evident after 9 h, a clinically relevant result because these products are typically applied 2 to 4 times daily. Based on these observations, liposome gel 1% formulation of diclofenac may have a clinical advantage compared with the emulsion gel 1.16% formulation.

Factors Related to the Use of Topical vs. Oral NSAIDs for Sprains, Strains, and Contusions in a Senior Population: A Retrospective Analysis of Administrative Claims Data

BACKGROUND

Research to date on sprains, strains, and contusions has focused mainly on the analysis of sports-related injuries, occupational injuries, injuries resulting from automobile accidents, and severe injuries that result in inpatient hospital stays. Little is known about real-world acute sprains, strains, and contusions in an aging population. Patients may be treated with over-the-counter, oral, non-steroidal anti-inflammatory drugs (NSAIDs) for acute sprains, strains, and contusions or may require the use of prescription NSAIDs. For sprains, strains, and contusions treated with prescription NSAIDs, the choice of topical administration or oral administration likely depends on a number of factors such as age and comorbid conditions.

OBJECTIVES

The objective of the study was to identify factors associated with the use of a prescription topical NSAID or a prescription oral NSAID for the treatment of sprains, strains, and contusions among patients aged 65-89 years enrolled in the Medicare Advantage with Prescription Drug plan.

METHODS

The study sample was selected from the Humana Research Database (Louisville, KY, USA). Study subjects were identified as patients enrolled in Medicare Advantage with Prescription Drug plans, aged 65-89 years, having a medical claim with an International Classification of Diseases, Ninth Revision, Clinical Modification indicative of an acute sprain, strain, and contusion between 1 January, 2010 and 31 March, 2014 (identification period). The date of the first claim was considered the index date, and subjects were required to have 12 months of continuous enrollment before the index date and a minimum of 3 months continuous enrollment after the index date. Prescription NSAID use during the 3 months after the index sprain, strain, and contusion diagnosis was required for study inclusion and was identified based on a pharmacy claim for a topical or an oral NSAID. Patients with prescription NSAID use leading up to the sprains, strains, and contusions were excluded. Potential factors related to the use of a topical vs. oral NSAID were identified using stepwise logistic regression with backward elimination.

RESULTS

After applying the inclusion and exclusion criteria, 42,283 patients were prescribed an oral or topical NSAID (39,294 oral; 2989 topical) within 3 months of the index sprain, strain, and contusion diagnosis. After applying stepwise logistic regression, and retaining variables with statistically significant parameter estimates (p < 0.05), use of topical NSAIDs was higher among female individuals [odds ratio and 95% confidence interval = 1.34 (1.24-1.45)], and appeared to increase with age [odds ratio = 1.04 (1.04-1.05)]. Topical NSAID use was lower in the Midwest region [odds ratio = 0.85 (0.77-0.94)] in comparison to the Southern region. Clinical factors associated with topical NSAID use included Elixhauser Comorbidity Index score [odds ratio = 1.06 (1.04-1.09)], medication burden [odds ratio = 1.06 (1.04-1.08), pill burden [odds ratio = 1.02 (1.01-1.03), specific comorbid conditions, including site-specific osteoarthritis of the upper arm [odds ratio = 2.34 (1.19-4.60)], ankle/foot [odds ratio = 1.46 (1.14-1.87)], or lower leg [odds ratio = 1.21 (1.07-1.36)], myofascial pain [odds ratio = 1.31 (1.21-1.42)], gastrointestinal/hepatic disorders [odds ratio = 1.15 (1.05-1.25)], systemic/central pain [odds ratio = 1.12 (1.01-1.23)], and cataracts [odds ratio = 1.10 (1.02-1.20)]. Conversely, a diagnosis of diabetes mellitus was related to use of an oral NSAID rather than a topical NSAID [odds ratio = 0.86 (0.78-0.94)]. Diagnosis of the index sprain, strain, and contusion in an emergency department instead of a physician's office was also associated with oral NSAID use [odds ratio = 0.42 (0.37-0.47)].

CONCLUSIONS

Topical NSAIDs were used less often than oral NSAIDs following a sprain, strain, or contusion. Age, medication burden, pill burden, evidence of gastrointestinal disorder, and evidence of certain pain-related conditions were significant factors associated with topical NSAID as opposed to oral NSAID use. In comparison to oral NSAIDs, topical NSAIDs were more likely to be prescribed in a physician's office than an emergency department, possibly because a patient's physician has a better understanding of the patient's concomitant medications and comorbidities. Although topical NSAIDs were more likely to be used than oral NSAIDs in patients with gastrointestinal disorders, the use of oral NSAIDs among patients with gastrointestinal bleeding was substantial.

A Pharmacokinetic Study of an Ibuprofen Topical Patch in Healthy Male and Female Adult Volunteers

The pharmacokinetics of a novel locally applied ibuprofen topical patch was evaluated. Healthy subjects (n = 28) were administered a 200-mg ibuprofen patch every 24 hours for 5 days, and steady-state pharmacokinetics was determined. The amount of ibuprofen remaining in the patch following each patch removal was also assessed. The maximum steady-state drug concentration and area under the concentration curve from time 0 on day 5 (t = 0) to the 24-hours sample on day 6 were 514 ng/mL (95% CI 439 to 603 ng/mL) and 9.78 kg·h/mL (95% CI 8.43 to 11.4 kg·h/mL), respectively. Maximum ibuprofen concentration on day 5 occurred at 20 hours post-patch application. No evidence of drug accumulation was observed, and steady state was achieved between days 2 and 5. Ibuprofen levels attenuated rapidly to baseline within 24 hours after treatment discontinuation. The amount of ibuprofen remaining in the patch was high (≥80%). Treatment-emergent adverse events were generally mild, with the most prevalent being headache (n = 6; 21.4%). Only 4 TEAEs were considered related to the ibuprofen patch: paresthesia (n = 1), headache (n = 2), and pruritic rash (n = 1). The study found that the systematic absorption of ibuprofen from a 200-mg patch was low and that the levels of ibuprofen leaving the patch over a 24-hour period are consistent with levels required for therapeutic relief as shown in other studies.

Gastrointestinal bleeding associated with chronic excessive use overdosing with topical ketoprofen patch in elderly patient

PURPOSE

Topical ketoprofen patch has been developed to reduce the risk of systemic adverse effects such as gastrointestinal injury and renal toxicity.

MATERIALS AND METHODS

We reported here a case of lower intestinal bleeding associated with chronic excessive use of topical ketoprofen patch in an elderly patient.

RESULTS

A 74-year-old female visited to the outpatient clinic of the Gifu University Hospital and admitted thereafter. She had fecal occult blood and anemia. Enteroscopic examination showed several ulcerative lesions and a protruded lesion accompanied with redness in the small intestinal mucosa. She used 8 sheets of 20 mg ketoprofen patch every day for a long period to relieve pain in the shoulder, lower back and lower limb. She had no diseases that are related to the initiation of gastrointestinal bleeding, including infection, inflammatory bowel disease, autoimmune disease and malignant disease. Thus, the present lower intestinal bleeding was concluded to be due to the use of topical ketoprofen patch. The symptoms were recovered after cessation of the patch.

CONCLUSIONS

Extensive care should be taken to avoid ulcerative intestinal hemorrhage to elderly patients receiving multiple doses of non-steroidal anti-inflammatory drug patch for multiple days.

Consensus recommendations for managing osteoarthritic pain with topical NSAIDs in Asia-Pacific

Osteoarthritis prevalence is expected to increase markedly in the Asia-Pacific region due to rapid population aging. Identifying effective and safe therapeutic options to manage osteoarthritic pain is viewed as a priority. The Asia-Pacific Experts on Topical Analgesics Advisory Board developed consensus statements for use of topical NSAIDs in musculoskeletal pain. Evidence supporting these statements in osteoarthritic pain was reviewed. Best available evidence indicates that topical NSAIDs have a moderate effect on relief of osteoarthritic pain, comparable to that of oral NSAIDs but with a better risk-to-benefit ratio. International clinical practice guidelines recommend topical NSAIDs on par with or ahead of oral NSAIDs for pain management in patients with knee and hand osteoarthritis, and as the first-line choice in persons aged ≥75 years.

Efficacy and tolerability of a new ibuprofen 200mg plaster in patients with acute sports-related traumatic blunt soft tissue injury/contusion

BACKGROUND

Ibuprofen is used for the treatment of non-serious pain. This study assessed the efficacy and safety of a new ibuprofen plaster for the treatment of pain associated with acute sports impact injuries/contusions.

METHODS

In this randomised, double-blind, multi-centre, placebo controlled, parallel group study, adults (n = 130; 18-58 years of age) diagnosed with acute sports-related blunt soft tissue injury/contusion were randomized to receive either ibuprofen 200 mg plaster or placebo plaster. Plasters were administered once daily for five consecutive days. The primary assessment was area under the visual analogue scale (VAS) of pain on movement (POM) over 0 to three days (VAS AUC_0-3d). Other endpoints included algometry AUC from 0 to three days (AUC_0-3d) and 0 to five days (AUC_0-5d), to evaluate improvement of sensitivity at the injured site, and patient and investigator global assessment of efficacy. Safety was monitored throughout the study.

RESULTS

The ibuprofen plaster resulted in superior reduction in AUC_0-3d compared with placebo; the Least Squares (LS) mean difference was 662.82 mm*h in favour of the ibuprofen 200mg plaster (P = 0.0011). The greater improvement in VAS AUC of POM was also observed after 12 h, 24 h, and five days of therapy. Tenderness also significantly improved with the ibuprofen plaster compared with placebo; LS mean difference in algometry/tenderness AUC_0-3d was 1.87 N/cm²*d and AUC_0-5d was 1.87 N/cm²*d (P values ≤0.0004). At all study timepoints, a greater percentage of patients and investigators rated the effectiveness of the ibuprofen 200 mg plaster as good/excellent than the placebo plaster. Treatment-emergent adverse events for the ibuprofen plaster were few (≤1.5%) and were mild in severity.

CONCLUSIONS

The results of this study indicate 200 mg plaster is effective and safe for the treatment of pain due to acute sports-related traumatic blunt soft tissue injury/contusion in adults.

Efficacy and safety assessment of acute sports-related traumatic soft tissue injuries using a new ibuprofen medicated plaster: results from a randomized controlled clinical trial

OBJECTIVE

To investigate the efficacy and safety of a recently developed ibuprofen medicated plaster in the treatment of acute sports impact injuries/contusions.

METHODS

In this double-blind, multi-center, placebo-controlled, parallel group, phase 3 study (EudraCT Number: 2012-003257-2) patients (n = 132; ages 18 to 60 years) diagnosed with acute sports-related traumatic blunt soft tissue injury/contusion to the upper or lower limbs were randomized to receive either ibuprofen 200 mg plaster (n = 64) or placebo plaster (n = 68). Plasters were administered once daily for five consecutive days. The primary assessment was the area under the curve (AUC) of the visual analogue scale (VAS) of pain on movement (POM) over 0 to 72 h (VAS_0-72).

RESULTS

The ibuprofen medicated plaster was associated with a reduction in pain on movement (POM) based on lower VAS AUC_0-72h (2399.4 mm*h) compared with placebo (4078.9 mm*h) (least squares mean difference: - 1679.5 mm*h; P < 0.0001). The reduction in AUC of POM was also significantly greater for the ibuprofen medicated plaster compared with placebo at 12, 48, 24, and 120 h (P < 0.0001). Algometry/tenderness measurements found that the ibuprofen medicated plaster was associated with greater reduction in tenderness/pain than placebo at each timepoint (P values <0.0001). Seven patients experienced drug-related adverse events (n = 1 [1.6%] for the ibuprofen plaster, and n = 6 [8.8%] for placebo). All drug-related AEs were administration site reactions and were mild in intensity.

CONCLUSIONS

The results of this study indicate that ibuprofen medicated plaster results in rapid and clinically relevant reduction of pain in patients suffering from blunt musculoskeletal injuries or recurrent pain. The ibuprofen medicated plaster was well tolerated.

Cutaneous irritancy of an ibuprofen medicated plaster in healthy volunteers

OBJECTIVE

Ibuprofen is a commonly used non-steroidal anti-inflammatory drug administered to treat injuries, joint pain, and recurrent muscular skeletal pain. The aim of this study was to determine the cutaneous irritancy of a medicated ibuprofen plaster compared with a placebo plaster in healthy volunteers.

METHODS

Healthy volunteers (N = 31) were treated at the same time with one ibuprofen and one placebo plaster. The ibuprofen and placebo plaster were applied in a randomized fashion to sites on the left or right side of subjects' lower backs. At each scheduled visit, the plasters and applications sites were assessed for degree of adhesion and skin irritancy, respectively. The plasters were applied on study Days 1, 2, 3, 5, 8, 10, 12, 15, 17, and 19, with final plaster removal on Day 22.

RESULTS

The ibuprofen medicated plaster compared with placebo had a lower percentage of Grade 1 (23.3% vs. 46.7%, respectively), Grade 2 (10% vs. 20%), and ≥Grade 3 (3% vs. 16.1%) irritancy scores after 21 days of application. The mean irritation score across the study was 0.40 for the ibuprofen medicated plaster and 1.18 for the placebo plaster. The irritation score on Day 22 of the study was 0.53 for the ibuprofen medicated plaster and 1.50 for placebo. The placebo plaster was associated with a higher number of stopped applications due to Grade 3 or above skin reactions compared with the ibuprofen medicated plaster (5 vs. 1, respectively).

CONCLUSION

The ibuprofen medicated plaster was well tolerated and was associated with lower irritancy than the placebo plaster.

Skin penetration and tissue permeation after topical administration of diclofenac

OBJECTIVE

Topical delivery of drugs is an alternative to oral administration, often with similar efficacy but potentially a more favorable tolerability profile. However, topical formulations need to be able to penetrate the skin and permeate to the target areas in quantities sufficient to exert a therapeutic effect. Many factors can affect this process, including the physicochemical properties of the drug, the formulation used, and the site and mode of application. It is believed that measurement of drug concentrations at the sites of action may be an indicator of their likely efficacy. This review addresses these issues, with reference to topically administered diclofenac in osteoarthritis.

METHODS

Articles relevant to this review were identified after a systematic search of Medline and Embase, using the key words "diclofenac", "topical administration" and "osteoarthritis" in the search strategy.

RESULTS

The sparse data available indicate that topical diclofenac can penetrate and permeate to deeper tissues, with a lower plasma to tissue ratio than oral diclofenac. The tissue diclofenac levels after topical delivery are sustained over time (at least several hours). However, there is not enough data to establish how diclofenac levels in the joint compare with IC₅₀ levels (50% of the maximum inhibition of prostaglandin synthesis) established following oral administration.

CONCLUSIONS

After topical application, diclofenac can penetrate the skin and permeate to deeper tissues, where it reaches a concentration that appears to be sufficient to exert a therapeutic effect. More robust methods are required for in vivo characterization to better estimate the clinical efficacy of topically applied drugs.

Effects of anti-inflammatory (NSAID) treatment on human tendinopathic tissue

Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat tendinopathy, but evidence for this treatment is lacking, and little is known regarding effects of NSAIDs on human tendinopathic tendon. This study investigated the effects of NSAID treatment (ibuprofen) on human tendinopathic tendon, with changes in gene expression as the primary outcome, and tendon pain, function, and blood flow as secondary outcomes. Twenty-six adults (16 men, 10 women), diagnosed with chronic Achilles tendinopathy, were randomized to 1-wk treatment with ibuprofen (600 mg ×3/day) (n = 13) or placebo (n = 13) (double-blinded). Ibuprofen content in blood, visual analog scale score for tendon pain at rest and activity, Victorian Institute of Sports Assessment-Achilles (VISA-A) scores for tendon function, tendon thickness (with ultrasonography), and color Doppler were measured before and 1 h after treatment. After the last posttreatment test, a full-width tendon biopsy was taken from the affected area. Real-time-RT-PCR was used to assess expression of collagen I, collagen III, transforming growth factor (TGF-β) isoforms, cyclooxygenase-2 (COX-2), angiopoietin-like 4 (ANGPTL4), and cyclic AMP-dependent transcription factor (ATF3) in tendon tissue. Expression of collagens and TGF-β isoforms showed relatively low variation and was unaffected by ibuprofen treatment. Further, no changes were seen in tendon thickness or VISA-A score. The placebo treatment reduced the color Doppler (in tendon plus surrounding tissue) compared with the ibuprofen group and also increased the perception of pain at rest. In conclusion, there was no indication that short-term ibuprofen treatment affects gene expression in human chronic tendinopathic tendon or leads to any clear changes in tendon pain or function.NEW & NOTEWORTHY Nonsteroidal anti-inflammatory drugs are widely used in the treatment of tendinopathy, but little is known of the effects of these drugs on tendon tissue. We find that 1 wk of ibuprofen treatment has no effect on gene expression of collagen and related growth factors in adult human tendinopathic tendon in vivo (in spite of relatively low levels of variation in gene expression), suggesting that tendinopathic cells are not responsive to ibuprofen.

Ketorolac Tromethamine Spray Prevents Postendotracheal-Intubation-Induced Sore Throat after General Anesthesia

Background. Postoperative sore throat is one of the major complaints of general anesthesia in the postanesthesia care unit. This prospective study investigated the preventive effect of ketorolac tromethamine spray in postendotracheal-intubation-induced sore throat after general anesthesia. Methods. Surgical patients undergoing general anesthesia with endotracheal intubation were recruited from a medical center. Patients were randomly assigned to group K (treated with 5% ketorolac tromethamine spray) or group D (treated with distilled water spray). Before intubation, each endotracheal tube was sprayed with the appropriate solution by physicians over the 20 cm length of the cuff. Each group comprised 95 patients fitting the inclusion and exclusion criteria for whom complete data sets were collected. The intensity of the sore throat was measured at 1, 3, 6, and 24 h after surgery, and data were compared. Results. The two groups had similar characteristics. Postoperative sore throat was significantly less frequent in group K than in group D (p < 0.001) and the pain intensity was significantly lower in group K than in group D at each time point (all p < 0.001). Conclusions. This study demonstrated that preanesthesia 5% ketorolac tromethamine spray could effectively decrease postendotracheal-intubation-induced sore throat in patients undergoing general anesthesia.

Evolution to low-dose NSAID therapy

All NSAIDs are to varying degrees associated with gastrointestinal, cardiovascular and renal adverse effects (AEs). Differences in selectivity for inhibition of the COX isozymes (COX-1/COX-2) have been used as an indicator of the likelihood of experiencing an AE, but the measure of 'selectivity' commonly used is less than desirable, and selectivity has not yielded unequivocal superior safety. Recent guidelines recommend that NSAIDs be used at the lowest effective dose and for the shortest period of time. In response, 'low-dose' NSAID formulations have been developed. Such formulations may help by reducing overall systemic exposure, thereby reducing the frequency or severity of AEs. It seems timely to review the need, rationale and application of such an approach.

The effect of application site of spinal manipulative therapy (SMT) on spinal stiffness

BACKGROUND CONTEXT

Like other factors that can influence treatment efficacy (eg, dosage, frequency, time of day), the site of treatment application is known to affect various physical interventions such as topical anesthetics and cardiopulmonary resuscitation. Like these examples, spinal manipulative therapy (SMT) is a physical intervention that may exhibit maximal benefit when directed to a specific site. Whereas numerous studies of SMT efficacy have produced mixed results, few studies have taken into account the site of SMT application.

PURPOSE

To determine if the site of SMT application modulates the effect of SMT in an anesthetized feline model.

STUDY DESIGN

Spinal manipulative therapy applied to specific anatomic locations randomized in a Latin square design with a no-SMT control.

OUTCOME MEASURES

Physiologic measures (spinal stiffness).

METHODS

Simulated SMT was delivered by a validated mechanical apparatus to the intact lumbar spine of eight anesthetized felines at four unique sites: L6 spinous process, left L6 lamina, left L6 mammillary process, and L7 spinous process. To measure spinal stiffness, a separate indentation load was applied mechanically to the L6 spinous process before and after each SMT application. Spinal stiffness was calculated from the resulting force-displacement curve as the average stiffness (k) and terminal instantaneous stiffness (TIS).

RESULTS

Relative to the no-SMT control, significant decreases in spinal stiffness followed the SMT when L6 spinous and L6 lamina were used as the contact site. Terminal instantaneous stiffness significantly decreased -0.48 N/mm (upper, lower 95% confidence interval [-0.86, -0.09]) with L6 spinous as the contact site and decreased -0.44 N/mm (-0.82, -0.05), with the L6 lamina as the contact site. k increased 0.44 N/mm (-0.01, 088), using L6 spinous as the contact site.

CONCLUSIONS

Decreases in terminal spinal stiffness were observed after SMT delivered at some application sites but not the others. The results suggest that SMT contact site modulates SMT's effect on spinal stiffness in a feline model. Changes in spinal terminal instantaneous spinal stiffness were similar in magnitude and direction to those observed in symptomatic human subjects who report benefits after SMT.

Advances in NSAID development: evolution of diclofenac products using pharmaceutical technology

Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID) of the phenylacetic acid class with anti-inflammatory, analgesic, and antipyretic properties. Contrary to the action of many traditional NSAIDs, diclofenac inhibits cyclooxygenase (COX)-2 enzyme with greater potency than it does COX-1. Similar to other NSAIDs, diclofenac is associated with serious dose-dependent gastrointestinal, cardiovascular, and renal adverse effects. Since its introduction in 1973, a number of different diclofenac-containing drug products have been developed with the goal of improving efficacy, tolerability, and patient convenience. Delayed- and extended-release forms of diclofenac sodium were initially developed with the goal of improving the safety profile of diclofenac and providing convenient, once-daily dosing for the treatment of patients with chronic pain. New drug products consisting of diclofenac potassium salt were associated with faster absorption and rapid onset of pain relief. These include diclofenac potassium immediate-release tablets, diclofenac potassium liquid-filled soft gel capsules, and diclofenac potassium powder for oral solution. The advent of topical formulations of diclofenac enabled local treatment of pain and inflammation while minimizing systemic absorption of diclofenac. SoluMatrix diclofenac, consisting of submicron particles of diclofenac free acid and a proprietary combination of excipients, was developed to provide analgesic efficacy at reduced doses associated with lower systemic absorption. This review illustrates how pharmaceutical technology has been used to modify the pharmacokinetic properties of diclofenac, leading to the creation of novel drug products with improved clinical utility.

Peripheral synergism between tramadol and ibuprofen in the formalin test

Preclinical Research Analgesics with different mechanisms of action can be combined in order to obtain pharmacological synergism, employing lower doses of each agent, thus diminishing side effects. For instance, an atypical dual analgesic such as tramadol (TMD) and a nonsteroidal anti-inflammatory drug such as ibuprofen (IBU) are good candidates to be evaluated when combined and applied peripherally. The present study was conducted to evaluate possible local synergism between TMD and IBU when combined peripherally using the formalin test in rats. The effects of the individual analgesics and their combinations were evaluated simultaneously using a 5% formalin dilution. Dose-effect curves were determined for TMD (50-400 μg/paw) and IBU (1-100 μg/paw). Experimental effective doses were evaluated and isobolographic analyses were constructed to evaluate TMD-IBU combination synergism. Both drugs produced a dose-dependent analgesic effect when applied separately. Isobolographic analysis showed synergism during phase 1 (0-10 min) and phase 2 (15-60 min) when compared with theoretical doses (P < 0.05), with interaction indexes of 0.06 and 0.09, respectively. The present information supports the peripheral analgesic effect of TMD and IBU, especially when combined at appropriate doses.

Topical gels of etofenamate: in vitro and in vivo evaluation

Non-steroid anti-inflammatory drugs (NSAIDs), such as etofenamate, are among the most prescribed drugs used for their analgesic, anti-rheumatic, antipyretic and anti-inflammatory properties. Topical formulations have the main advantage of targeted delivery. However, drugs must overcome the skin due to its role as a physical and chemical barrier against the penetration of chemicals and microorganisms. This barrier must be altered to allow the permeation of drugs at a suitable rate to the desired site of activity. Permeation modulators can intercalate the skin outer layers causing structure disruption, opening an energetically favourable route for the drug to diffuse through. The aim of this work was the development of hydroalcoholic gels containing 5.0% (w/w) of etofenamate for topical administration with anti-inflammatory activity and enhanced drug delivery. The physical and chemical characterization, in vitro release and permeation studies and in vivo anti-inflammatory activity were assessed. The gel with 30% ethanol showed in vivo anti-inflammatory activity with suitable physical chemical and microbiologic characteristics. In vitro release and permeation studies revealed that the different amounts of ethanol used influenced the release profiles of etofenamate. Moreover, it was demonstrated that this formulation is an adequate vehicle for the etofenamate skin permeation.