Diclofenac: an update on its mechanism of action and safety profile

Synergistic effect of the interaction between curcumin and diclofenac on the formalin test in rats

The association of non-steroidal anti-inflammatory drugs with certain plant extracts can increase antinociceptive activity, permitting the use of lower doses and thus limiting side effects. Therefore, the aim objective of the current study was to examine the effects of curcumin on the nociception and pharmacokinetics of diclofenac in rats. Antinociception was assessed using the formalin test. Diluted formalin was injected subcutaneously into the dorsal surface of the right hind paw. Nociceptive behavior was quantified as the number of flinches of the injected paw during 60 min after injection, and a reduction in formalin-induced flinching was interpreted as an antinociceptive response. Rats were treated with oral diclofenac (1-31 mg/kg), curcumin (3.1-100 mg/kg) or the diclofenac-curcumin combination (2.4-38.4 mg/kg). To determine the possibility of a pharmacokinetic interaction, the oral bioavailability of diclofenac (10 mg/kg) was studied in presence and the absence of curcumin (31 mg/kg). Diclofenac, curcumin, or diclofenac-curcumin combination produced an antinociceptive effect on the formalin test. ED30 values were estimated for the individual drugs, and an isobologram was constructed. The derived theoretical ED30 for the antinociceptive effect (19.2 mg/kg) was significantly different from the observed experimental ED30 value (9.8 mg/kg); hence, the interaction between diclofenac and curcumin that mediates the antinociceptive effect was synergistic. Notwithstanding, the interaction does not appear to involve pharmacokinetic mechanisms, as oral curcumin failed to produce any significant alteration in oral diclofenac bioavailability. Data suggest that the diclofenac-curcumin combination can interact at the systemic level and may have therapeutic advantages for the clinical treatment of inflammatory pain.

Efficacy and safety profile of combination of tramadol-diclofenac versus tramadol-paracetamol in patients with acute musculoskeletal conditions, postoperative pain, and acute flare of osteoarthritis and rheumatoid arthritis: a Phase III, 5-day open-label study

Objective

We aimed to evaluate the safety and efficacy of a fixed-dose combination (FDC) of tramadol and diclofenac versus a standard approved FDC of tramadol and paracetamol, in patients with acute moderate to severe pain.

Methods

A total of 204 patients with moderate to severe pain due to acute musculoskeletal conditions (n=52), acute flare of osteoarthritis (n=52), acute flare of rheumatoid arthritis (n=50), or postoperative pain (n=50) were enrolled in the study at baseline. Each disease category was then randomized to receive either of two treatments for 5 days: group A received an FDC of immediate-release tramadol hydrochloride (50 mg) and sustained-release diclofenac sodium (75 mg) (one tablet, twice daily), and group B received an FDC of tramadol hydrochloride (37.5 mg) and paracetamol (325 mg) (two tablets every 4–6 hours, up to a maximum of eight tablets daily). The primary efficacy end points were reductions in pain intensity from baseline at day 3 and day 5 as assessed by a Visual Analog Scale (VAS) score.

Results

Group A showed a significant reduction in the VAS score for overall pain from baseline on day 3 (P=0.001) and day 5 (P<0.0001) as compared with group B. The combination of tramadol-diclofenac resulted in few mild to moderate adverse events (nausea, vomiting, epigastric pain, and gastritis), which required minimal management, without any treatment discontinuation. The number of adverse events in group A was nine (8.82%) compared with 22 (21.78%) in group B, after 5 days of treatment.

Conclusion

An FDC of tramadol-diclofenac showed a significantly greater reduction in pain intensity and was well tolerated compared with tramadol-paracetamol, resulting in better analgesia in patients suffering from moderate to severe pain due to acute musculoskeletal conditions, postoperative pain following orthopedic surgery, or acute flare of osteoarthritis and rheumatoid arthritis.

Topical analgesic, anti-inflammatory and antioxidant properties of Oxybaphus nyctagineus: phytochemical characterization of active fractions

ETHNOPHARMACOLOGICAL RELEVANCE

Oxybaphus nyctagineus (Michx.) Sweet has traditionally been used by several Native American tribes predominantly as a topical anti-inflammatory and analgesic agent.

AIM OF THE STUDY

To evaluate the antioxidant, analgesic and anti-inflammatory activity of the extracts prepared from the aerial parts of Oxybaphus nyctagineus and to characterize the major chemical constituents of the bioactive extracts.

MATERIALS AND METHODS

Crude polar and apolar extracts (PCE and ACE) of the herb of Oxybaphus nyctagineus were prepared and tested in the models of the CFA-induced hyperalgesia in rat knee and carrageenan-induced paw edema in rat. To identify the active compounds, subfractions were prepared by column chromatography and subjected in vitro assays, such as antioxidant assays (DPPH, peroxynitrite (ONOO-) scavenging), and the LPS-induced IL-1β release test in human monocytes. Preparative HPLC was employed for the isolation of active substances, while phytochemical analysis was performed by mean of LC-MS/MS and NMR.

RESULTS

The topically administered PCE and ACE of Oxybaphus nyctagineus demonstrated a significant analgesic and anti-inflammatory effect in the inflammation animal models. The subfraction A4 of ACE and the subfraction P5 of PCE considerably inhibited the LPS-induced IL-1β release in human monocytes, while the strongest activity was localized in the subfraction P5 in the antioxidant assays. The HPLC-MS/MS and NMR analysis revealed that 6-methoxyflavonol diglycosides, namely patuletin-3-O-robinobioside (1), 6-methoxykaempferol-3-O-robinobioside (2), spinacetin-3-O-robinobioside (3), and hydroxy-polyenoic fatty acids, namely corchorifatty acid B (4), 9-hydroxy-10E,12Z,15Z-octadecatrienoic acid (9-HOT acid) (5), and 9-hydroxy-10E,12Z-octadecadienoic acid (9-HOD acid) (6) were present in PCE, and in ACE as major compounds.

CONCLUSION

The results of this study established a pharmacological evidence for the traditional use of Oxybaphus nyctagineus as an anti-inflammatory agent used topically, and provided data on its phytochemical composition for the first time.

Diclofenac potassium powder for oral solution: a review of its use in patients with acute migraine

Diclofenac potassium powder for oral solution (Voltfast(®), Catafast(®), Cambia(®); hereafter referred to as diclofenac potassium powder) is a non-steroidal anti-inflammatory drug (NSAID), and is indicated for the acute treatment of migraine. This article reviews the pharmacological properties of diclofenac potassium powder and its efficacy and tolerability in patients with acute migraine. Diclofenac potassium powder was clinically efficacious and generally well tolerated in placebo-controlled trials in patients with this indication; it was more effective than diclofenac potassium tablets with regard to the primary endpoint of 2-h pain relief as well as in several important secondary endpoints, such as time to onset of analgesic action. The oral powder-for-solution formulation of diclofenac potassium is a useful option in the acute treatment of migraine with or without aura.

Formulation of diclofenac for dermal delivery

Diclofenac (DF) was first synthesized in the 1960's and is currently available as ophthalmic, oral, parenteral, rectal and skin preparations. This review focuses on the administration of DF to the skin. As a member of the non-steroidal anti-inflammatory (NSAID) group of drugs the primary indications of DF are for the management of inflammation and pain but it is also used to treat actinic keratosis. The specific aims of this paper are to: (i) provide an overview of the pharmacokinetics and metabolism of DF following oral and topical administration; (ii) examine critically the various formulation approaches which have been investigated to enhance dermal delivery of DF; and (iii) identify new formulation strategies for enhanced DF skin penetration.

Pharmacological potential of Populus nigra extract as antioxidant, anti-inflammatory, cardiovascular and hepatoprotective agent

OBJECTIVE

To evaluate antioxidant, anti-inflammatory, hepatoprotective and vasorelaxant activities of Populus nigra flower buds ethanolic extract.

METHODS

Antioxidant and anti-inflammatory activities of the extract were assessed using respectively the ABTS test and the animal model of carrageenan-induced paw edema. Protection from hepatic toxicity caused by aluminum was examined by histopathologic analysis of liver sections. Vasorelaxant effect was estimated in endothelium-intact and -rubbed rings of porcine coronary arteries precontracted with high concentration of U46619.

RESULTS

The results showed a moderate antioxidant activity (40%), but potent anti-inflammatory activity (49.9%) on carrageenan-induced mice paw edema, and also as revealed by histopathologic examination, complete protection against AlCl₃-induced hepatic toxicity. Relaxant effects of the same extract on vascular preparation from porcine aorta precontracted with high concentration of U46619 were considerable at 10⁻¹ g/L, and comparable (P>0.05) between endothelium-intact (67.74%, IC₅₀=0.04 mg/mL) and -rubbed (72.72%, IC₅₀=0.075 mg/mL) aortic rings.

CONCLUSIONS

The extract exerted significant anti-inflammatory, hepatoprotective and vasorelaxant activities, the latter being endothelium-independent believed to be mediated mainly by the ability of components present in the extract to exert antioxidant properties, probably related to an inhibition of Ca²⁺ influx.

Synthesis, In Vitro and In Vivo Evaluation of the N-ethoxycarbonylmorpholine Ester of Diclofenac as a Prodrug

The N-ethoxycarbonylmorpholine moiety was evaluated as a novel prodrug moiety for carboxylic acid containing drugs represented by diclofenac (1). Compound 2, the N-ethoxycarbonylmorpholine ester of diclofenac was synthesized and evaluated as a potential prodrug. The stability of the synthesized prodrug was evaluated in solutions of pH 1 and 7.4, and in plasma. The ester’s half lives were found to be 8 h, 47 h and 21 min in pH 1, pH 7.4 and plasma, respectively. Equimolar doses of diclofenac sodium and its synthesized prodrug were administered orally to a group of rabbits in a crossover study to evaluate their pharmacokinetic parameters. The prodrug 2 shows a similar rate and extent of absorption as the parent drug (1). The ulcerogenicity of the prepared prodrug was evaluated and compared with the parent drug. The prodrug showed less ulcerogenicity as detected by fewer number and smaller size of ulcers. In conclusion, the newly synthesized N-ethoxycarbonylmorpholine ester of diclofenac prodrug showed appropriate stability properties at different pHs, similar pharmacokinetic profile, and much less ulcerogenecity at the GIT compared to the parent drug diclofenac.

Manipulating ratio spectra for the spectrophotometric analysis of diclofenac sodium and pantoprazole sodium in laboratory mixtures and tablet formulation

Objective. Three sensitive, selective, and precise spectrophotometric methods based on manipulation of ratio spectra, have been developed and validated for the determination of diclofenac sodium and pantoprazole sodium. Materials and Methods. The first method is based on ratio spectra peak to peak measurement using the amplitudes at 251 and 318 nm; the second method involves the first derivative of the ratio spectra (Δλ = 4 nm) using the peak amplitudes at 326.0 nm for diclofenac sodium and 337.0 nm for pantoprazole sodium. The third is the method of mean centering of ratio spectra using the values at 318.0 nm for both the analytes. Results. All the three methods were linear over the concentration range of 2.0–24.0 μg/mL for diclofenac sodium and 2.0–20.0 μg/mL for pantoprazole sodium. The methods were validated according to the ICH guidelines and accuracy, precision, repeatability, and robustness are found to be within the acceptable limit. The results of single factor ANOVA analysis indicated that there is no significant difference among the developed methods. Conclusions. The developed methods provided simple resolution of this binary combination from laboratory mixtures and pharmaceutical preparations and can be conveniently adopted for routine quality control analysis.

Analgesic efficacy and safety of a novel injectable formulation of diclofenac compared with intravenous ketorolac and placebo after orthopedic surgery: a multicenter, randomized, double-blinded, multiple-dose trial

OBJECTIVES

A novel injectable formulation of diclofenac, Dyloject, utilizes hydroxypropyl-β-cyclodextrin (HPβCD) as a solubilizing agent, allowing dosing as a small-volume intravenous bolus for postoperative pain. In this test of the efficacy and safety of HPβCD diclofenac, we hypothesized that HPβCD diclofenac would relieve moderate and severe pain after orthopedic surgery.

PATIENTS AND METHODS

Adults 18 to 85 years old with moderate and severe pain within 6 hours after surgery were randomized to HPβCD diclofenac, ketorolac tromethamine, or placebo, and stratified by risk cohort. The HPβCD diclofenac non-high-risk cohort dose was 37.5 mg, the high-risk cohort received 18.75 mg, and patients ≥95 kg received 50 mg. The ketorolac dose was 30 mg in the non-high-risk and high-weight cohorts and 15 mg in the high-risk cohort. Rescue intravenous morphine was given for pain as needed. Efficacy was measured by the sum of pain intensity differences (SPID).

RESULTS

Mean SPID scores of 277 patients were significantly better with HPβCD diclofenac and ketorolac than with placebo (P<0.0001), across all risk cohorts (P<0.05). HPβCD diclofenac was associated with better SPID scores, faster onset of analgesia, and significantly lower opioid requirement (P<0.008) than ketorolac. In patients more than or equal to 65 years, HPβCD diclofenac was associated with significantly better analgesic efficacy (P=0.05), and lower opioid requirement versus ketorolac. The incidence of treatment-related adverse events was similar across groups.

DISCUSSION

HPβCD diclofenac is safe and efficacious for acute moderate and severe pain after orthopedic surgery and significantly spares morphine use.

Antinociceptive synergy between diclofenac and morphine after local injection into the inflamed site

BACKGROUND

Combinations of non-steroidal anti-inflammatory drugs with opioids are frequently used to reduce opioid doses required in the clinical management of acute pain. The present study was designed to evaluate the possible antinociceptive interaction between morphine and diclofenac at peripheral level in male rats.

METHODS

Drugs were chosen based on their efficacy in the treatment of this kind of pain and as representative drugs of their respective analgesic groups. For the formalin test, 50 μ of 1% formalin solution was injected subcutaneously into the right hind paw. The interaction between morphine and diclofenac was evaluated by using isobolographic analysis and interaction index. Drug interaction was examined by administering fixed-ratio combinations of morphine-diclofenac (1 : 1 and 3 : 1) of their respective ED30 fractions.

RESULTS

Diclofenac and morphine reduced flinching behavior in a dose-dependent manner during phase 2 but not phase 1 of the formalin test. Isobolographic analysis showed a synergistic interaction for the combination of morphine and diclofenac after local peripheral administration.

CONCLUSIONS

Data suggest that the combination of morphine with diclofenac at the site of injury is synergistic and could be useful in the treatment of wounds, bruises, rheumatisms and other painful peripheral conditions associated with an inflammatory process.

Effects of topical nasal steroids and diclofenac on the nasal mucosa during hyperbaric oxygen therapy: a double-blind experimental study

We aimed to evaluate nasal mucosal changes and efficiency of nasal steroids and diclofenac on nasal mucosa during hyperbaric oxygen (HBO) treatment. Forty adult Albino-Wistar rats were randomized into four groups. Group 1 (control group) (n = 10) not exposed to hyperbaric or enhanced oxygen concentrations; group 2 (HBO group) (n = 10) underwent only HBO treatment; group 3 (n = 10) received HBO and intranasal mometasone furoate (10 μl/day); group 4 (n = 10) treated with HBO and diclofenac sodium (10 mg/kg/day ip). Specimens of nasal mucosa were collected after sacrificing and dissection of animals. The specimens were processed for light microscopic evaluation, and then evaluated histopathologically for fibroblastic proliferation and inflammation. Regarding the scores of inflammation, the level of inflammation in the control group was significantly less severe than the other groups (p < 0.05). Evaluation of the fibrosis scores showed that the scores of both groups 2 and 4 were significantly increased (p < 0.05). There were no statistically significant differences between groups 2, 3, and 4 as for fibrosis and inflammation (p > 0.05). Chronic HBO treatment induced mild inflammation of the nasal mucosa. These effects cannot be prevented adequately by administration of nasal steroids and diclofenac.

Inhibiting cycloxygenase and ornithine decarboxylase by diclofenac and alpha-difluoromethylornithine blocks cutaneous SCCs by targeting Akt-ERK axis

Non-melanoma skin cancer (NMSC) is the most common type of skin cancer in Caucasian populations. Its increasing incidence has been a major public health concern. Elevated expressions of ODC and COX-2 are associated with both murine and human NMSCs. Inhibition of these molecular targets singly employing their respective small molecule inhibitors showed limited success. Here, we show that combined blockade of ODC and COX-2 using their potent inhibitors, DFMO and diclofenac respectively abrogates growth of A431 epidermal xenograft tumors in nu/nu mice by more than 90%. The tumor growth inhibition was associated with a diminution in the proliferation and enhancement in apoptosis. The proliferation markers such as PCNA and cyclin D1 were reduced. TUNEL-positive apoptotic cells and cleaved caspase-3 were increased in the residual tumors. These agents also manifested direct target-unrelated effects. Reduced expression of phosphorylated MAPKAP-2, ERK, and Akt (ser(473) & thr(308)) were noticed. The mechanism by which combined inhibition of ODC/COX attenuated tumor growth and invasion involved reduction in EMT. Akt activation by ODC+COX-2 over-expression was the key player in this regard as Akt inhibition manifested effects similar to those observed by the combined inhibition of ODC+COX-2 whereas forced over-expression of Akt resisted against DFMO+diclofenac treatment. These data suggest that ODC+COX-2 over-expression together leads to pathogenesis of aggressive and invasive cutaneous carcinomas by activating Akt signaling pathway, which through augmenting EMT contributes to tumor invasion.

Osteoarthritis of the hand II: chemistry, pharmacokinetics and pharmacodynamics of naproxen, and clinical outcome studies

Objective

This article aims to review osteoarthritis of the hand and the role of the non-steroidal anti-inflammatory drug (NSAID) naproxen on its management. We discuss the chemical and pharmacological properties of naproxen and the NSAID class, with an emphasis on its mechanism and adverse reactions. In the context of part I of this paper in characterizing hand osteoarthritis (OA), we review clinical trials that have been conducted involving hand OA and naproxen.

Key findings

The therapeutic effect of NSAIDs stems from its role on inhibiting cyclo-oxygenase (COX)-1 or COX-2 enzyme activity in the body. These enzymes play a major role in maintaining several functions in the body and due NSAIDs' inhibitory effects; many principle adverse reactions occur with the use of NSAIDs such as: gastrointestinal tract issues, cardiovascular risks, renal, hepatic, central nervous system and cutaneous. Review of clinical trials involving naproxen and hand OA show that it is significantly more efficacious when compared with placebo.

Summary

These studies, along with the finding that naproxen is of least cardiovascular risk in the NSAID class, may show that it can be part of one of the approaches in managing the condition. It is important to note that the optimal NSAID to use varies for each individual. The finding that the use of naproxen leads to the smallest increase in cardiovascular risk appeals to those at-risk individuals who suffer from OA and require pharmacological treatment for relief.

Mouse model phenotypes provide information about human drug targets

Motivation: Methods for computational drug target identification use information from diverse information sources to predict or prioritize drug targets for known drugs. One set of resources that has been relatively neglected for drug repurposing is animal model phenotype.

Results: We investigate the use of mouse model phenotypes for drug target identification. To achieve this goal, we first integrate mouse model phenotypes and drug effects, and then systematically compare the phenotypic similarity between mouse models and drug effect profiles. We find a high similarity between phenotypes resulting from loss-of-function mutations and drug effects resulting from the inhibition of a protein through a drug action, and demonstrate how this approach can be used to suggest candidate drug targets.

Availability and implementation: Analysis code and supplementary data files are available on the project Web site at https://drugeffects.googlecode.com.

Contact:leechuck@leechuck.de or roh25@aber.ac.uk

Supplementary information:Supplementary data are available at Bioinformatics online.

Cardiac safety of diclofenac at a single dose in ram

Nonsteroidal anti-inflammatory drugs are frequently prescribed drug group in human and veterinary medicine. However, diclofenac, a traditional nonsteroidal anti-inflammatory drug, related to cardiotoxicity is reported, and blood cardiac damage markers may increase within the first hours after damage. The aim of the current research was to determine the effect of diclofenac on the blood cardiac damage markers. Single dose of diclofenac (2.5 mg/kg, IM) was injected to 6 rams. Blood samples were collected in before (0 hour, control) and 6 hours after injection. Specific (troponin I, and creatine kinase-MB) and nonspecific (lactate dehydrogenase, aspartate aminotransferase) blood cardiac damage marker concentrations, routine biochemical (hepatic damage, renal damage, lipid metabolism, glucose, and phosphorus) parameters, and hemogram values were measured. Diclofenac increased (P < 0.05) specific (troponin I) and nonspecific cardiac (lactate dehydrogenase, aspartate aminotransferase), hepatic (aspartate aminotransferase, alkaline phosphatase, and alanine aminotransferase), and muscular (creatine kinase) damage markers and high density lipoprotein level, while it decreased (P < 0.05) low density lipoprotein level. Moreover, diclofenac decreased (P < 0.05) white blood cell counts and increased (P < 0.05) red blood cell counts. In conclusion, it may be stated that diclofenac shows slight cardiotoxicity, whereas it may show potent hepatic and muscular damage effects at an intramuscularly single dose in sheep. Thereby, repeated injections of diclofenac may be more harmful in sheep.

Enhanced Anti-Inflammatory Effects of Nanoencapsulated Diclofenac

This study was conducted to compare the anti-inflammatory efficacy of nanoencapsulated and free-form diclofenac in rat. Diclofenac-loaded liposomes were prepared using the proliposome method. The anti-inflammatory effects of nanoencapsulated and free diclofenac were evaluated using the carrageenan-induced paw edema, formalin-induced paw licking and cotton-pellet-induced granuloma tests in vivo. For carrageenan-induced paw edema, 2 and 20 mg/kg liposome-encapsulated diclofenac showed significant paw volume reduction compared to free form diclofenac of equivalent dosage groups. In the formalin test, significant reduction in paw-licking time was observed in late phase for both liposome-encapsulated and free-form diclofenac (2 and 20 mg/kg) with the percentage of inhibition of 28.62, 60.17% for free-form diclofenac and 31.45, 78.84% for liposome-encapsulated diclofenac, respectively. In cotton-pellet-induced granuloma test 20 mg/kg free-form diclofenac showed significant reduction in the size of granuloma in both transudative and granuloma weight with percentage of inhibition of 42.93 and 49.26%, respectively, when compared to controls. Interestingly, 20 mg/kg nanoencapsulated diclofenac showed a larger reduction of the parameter with percentage of inhibition of 48.43 and 63.55%, respectively. Collectively, these results indicated that nanoencapsulated diclofenac exhibited statistically higher efficacy than free-form diclofenac when orally administered. Hence, clinical dosage may be reduced thereby reducing the drug's adverse effects.

Parenteral diclofenac infusion significantly decreases brain-tissue oxygen tension in patients with poor-grade aneurysmal subarachnoid hemorrhage

Introduction

Diclofenac, a nonsteroidal antiinflammatory drug, is commonly used as antipyretic therapy in intensive care. The purpose of this study was to investigate the effects of parenteral diclofenac infusion on brain homeostasis, including brain-tissue oxygen tension (P_btO₂) and brain metabolism after aneurysmal subarachnoid hemorrhage (aSAH).

Methods

We conducted a prospective, observational study with retrospective analysis of 21 consecutive aSAH patients with multimodal neuromonitoring. Cerebral perfusion pressure (CPP), mean arterial pressure (MAP), intracranial pressure (ICP), body temperature, and P_btO₂ were analyzed after parenteral diclofenac infusion administered over a 34-minute period (20 to 45 IQR). Data are given as mean ± standard error of mean and median with interquartile range (IQR), as appropriate. Time-series data were analyzed by using a general linear model extended by generalized estimation equations (GEEs).

Results

One-hundred twenty-three interventions were analyzed. Body temperature decreased from 38.3°C ± 0.05°C by 0.8°C ± 0.06°C (P < 0.001). A 10% decrease in MAP and CPP (P < 0.001) necessitated an increase of vasopressors in 26% (n = 32), colloids in 33% (n = 41), and crystalloids in 5% (n = 7) of interventions. P_btO₂ decreased by 13% from a baseline value of 28.1 ± 2.2 mm Hg, resulting in brain-tissue hypoxia (P_btO₂ <20 mm Hg) in 38% (n = 8) of patients and 35% (n = 43) of interventions. P_btO₂ <30 mm Hg before intervention was associated with brain-tissue hypoxia after parenteral diclofenac infusion (likelihood ratio, 40; AUC, 93%; 95% confidence interval (CI), 87% to 99%; P < 0.001). Cerebral metabolism showed no significant changes after parenteral diclofenac infusion.

Conclusions

Parenteral diclofenac infusion after aSAH effectively reduces body temperature, but may lead to CPP decrease and brain-tissue hypoxia, which were both associated with poor outcome after aSAH.

Safety of a novel parenteral formulation of diclofenac after major orthopedic or abdominal/pelvic surgery in a population including anticoagulated, elderly or renally insufficient patients: an open-label, multiday, repeated dose clinical trial

OBJECTIVE

Decisions to use or avoid nonsteroidal anti-inflammatory drugs (NSAIDs) for postsurgical pain are often influenced by concerns about bleeding and renal adverse effects. The objective of this study was to evaluate the safety of a novel parenteral NSAID, hydroxypropyl-β-cyclodextrin (HPβCD) diclofenac, in a large postsurgical patient population, with particular focus on bleeding and renal effects.

METHODS

This was a large open-label study in adult patients with acute moderate-to-severe pain following major surgery. Patients received ≥2 days of continuous treatment with HPβCD diclofenac, administered as a small-volume bolus injection every 6 hours. Few exclusion criteria were applied in order to reflect surgical patient populations commonly managed in clinical practice. Adverse events (AEs) were recorded throughout the study. The incidences of bleeding- and renal-related AEs were examined in patient subpopulations with known risk factors for NSAID-induced complications: advanced age, pre-existing renal insufficiency, concomitant anticoagulant use, prolonged exposure, elevated dosage, and major surgeries.

RESULTS

Of the total 971 patients studied, 38% were ≥65 years old (12% >75 years), 62% received concomitant anticoagulants, and 6% had pre-existing renal insufficiency. HPβCD diclofenac was well tolerated by the patient population. AE rates are presented by risk factor to enable clinicians to better describe renal- or bleeding-related AEs.

CONCLUSIONS

In addition to its previously demonstrated efficacy, this study provides evidence of HPβCD diclofenac's safety in a large postsurgical population including anticoagulated, elderly or renally insufficient patients. Because study exclusion criteria were minimal, these findings may be broadly generalizable to populations commonly treated in clinical practice.

Nonsteroidal anti-inflammatory drugs during pregnancy and the initiation of lactation

Nonsteroidal anti-inflammatory drugs (NSAIDs) and aspirin, which are available as "over-the counter" medications in most countries, are widely used by both pregnant and lactating women. They are popular non-opioid analgesics for the treatment of pain after vaginal and operative delivery. In addition, NSAIDs are used for tocolysis in premature labor, and low-dose aspirin has a role in the prevention of preeclampsia and recurrent miscarriage in antiphospholipid syndrome. NSAIDs and aspirin may affect fertility and increase the risk of early pregnancy loss. In the second trimester their use is considered reasonably safe, but has been associated with fetal cryptorchism. In the third trimester, NSAIDs and aspirin are usually avoided because of significant fetal risks such as renal injury, oligohydramnios, constriction of the ductus arteriosus (with potential for persistent pulmonary hypertension in the newborn), necrotizing enterocolitis, and intracranial hemorrhage. Maternal administration or ingestion of most NSAIDs results in low infant exposure via breastmilk, such that both cyclooxygenase-1 and cyclooxygenase-2 inhibitors are generally considered safe, and preferable to aspirin, when breastfeeding.

Effects of ibuprofen, diclofenac, naproxen, and piroxicam on the course of pregnancy and pregnancy outcome: a prospective cohort study

OBJECTIVE

To investigate the individual effects of ibuprofen, diclofenac, naproxen, and piroxicam on pregnancy outcome.

DESIGN

Cohort study.

SETTING

Norwegian population.

POPULATION

A total of 90 417 women and singleton child pairs.

METHODS

The Norwegian Mother and Child Cohort Study and Medical Birth Registry of Norway data sets were used.

MAIN OUTCOME MEASURES

Infant survival, congenital malformations, structural heart defects, neonatal complications, haemorrhage during pregnancy and postpartum, asthma at age of 18 months.

RESULTS

One or more of the four nonsteroidal anti-inflammatory drugs (NSAIDs) were used by 6511 pregnant women (7.2%). No effect on rates of infant survival, congenital malformation, or structural heart defects was found. The use of ibuprofen in the second trimester was significantly associated with low birthweight (adjusted OR 1.7, 95% CI 1.3-2.3), and ibuprofen use in the second and third trimesters was significantly associated with asthma in 18-month-old children (adjusted OR 1.5, 95% CI 1.2-1.9; adjusted OR 1.5, 95% CI 1.1-2.1). The use of diclofenac in the second trimester was significantly associated with low birthweight (adjusted OR 3.1, 95% CI 1.1-9.0), whereas diclofenac use in the third trimester was significantly associated with maternal vaginal bleeding (adjusted OR 1.8, 95% CI 1.1-3.0). No associations with other neonatal complications were found.

CONCLUSIONS

The lack of associations with congenital malformations is reassuring. The significant association between diclofenac and ibuprofen use late in pregnancy, and maternal bleeding and asthma in the child, respectively, is consistent with their pharmacological effects. The increased risk of low birthweight may partly have been caused by underlying inflammatory conditions, and was reassuringly similar to the expected baseline risk of low birthweight.

Lower gastrointestinal adverse effects of NSAIDS: an extreme example of a common problem

Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly prescribed throughout the world. Their adverse effects on the upper gastrointestinal (GI) tract are well documented and well known among clinicians and often mitigated against by coprescribing proton pump inhibitors. This case exemplifies the lesser-known lower GI adverse effects of NSAIDS. A 55-year-old patient took a large mixed overdose including more than 11 g of diclofenac. He went onto require subtotal colectomy following widespread perforations of an ulcerated large bowel as a direct result of exposure to a high-dose of NSAIDs. However, the upper GI tract remained relatively unaffected in comparison. This case highlights important lessons from recent literature identifying an increasing incidence of lower GI complications of NSAIDS, the limited protective effect of PPIs on the lower GI tract and the need for clinicians to now consider the integrity of the whole GI tract when prescribing NSAIDS.

A proteomic evaluation of the effects of the pharmaceuticals diclofenac and gemfibrozil on marine mussels (Mytilus spp.): evidence for chronic sublethal effects on stress-response proteins

Human pharmaceuticals (e.g. the lipid regulator gemfibrozil and the non-steroidal anti-inflammatory drug diclofenac) are an emerging environmental threat in the aquatic environment. This study aimed to evaluate sublethal effects of these two commonly found pharmaceuticals on the protein profiles of marine mussels (Mytilus spp.). Mytilus spp. was exposed to environmentally relevant and elevated concentrations (1 and 1000 µg/l respectively) of both drugs for 14 days. In addition, mussels were maintained for seven days post treatment to examine the potential of blue mussels to recover from such an exposure. Differential protein expression signatures (PES) in the digestive gland of mussels were obtained using two-dimensional gel electrophoresis after 7, 14, and 21 days of exposure. Twelve spots were significantly increased or decreased by gemfibrozil and/or diclofenac, seven of which were successfully identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. These proteins were involved in energy metabolism, oxidative stress response, protein folding, and immune responses. Changes in the PES over time suggested that mussels were still experiencing oxidative stress for up to seven days post exposure. In addition, a suite of biomarkers comprising glutathione transferase, lipid peroxidation, and DNA damage were studied. An oxidative stress response was confirmed by biomarker responses. To our knowledge, this is the first investigation using proteomics to assess the potential effects of human pharmaceuticals on a non-target species in an environmentally-relevant model. The successful application of this proteomic approach supports its potential use in pollution biomonitoring and highlights its ability to aid in the discovery of new biomarkers.

The α7 nicotinic ACh receptor agonist compound B and positive allosteric modulator PNU-120596 both alleviate inflammatory hyperalgesia and cytokine release in the rat

BACKGROUND AND PURPOSE

Agonists selective for the α7 nicotinic acetylcholine (nACh) receptor produce anti-hyperalgesic effects in rodent models of inflammatory pain, via direct actions on spinal pain circuits and possibly via attenuated release of peripheral pro-inflammatory mediators. Increasingly, allosteric modulation of ligand-gated receptors is recognized as a potential strategy to obtain desired efficacy in the absence of the putative adverse effects associated with agonist activation.

EXPERIMENTAL APPROACH

We compared the anti-hyperalgesic and anti-inflammatory effects of the α7 nACh receptor agonist compound B with the positive allosteric modulator (PAM) PNU-120596 and the standard non-steroidal anti-inflammatory drug (NSAID), diclofenac, in rats with hind paw inflammation induced by either formalin, carrageenan or complete Freund's adjuvant (CFA).

KEY RESULTS

When administered before carrageenan, both diclofenac (30 mg·kg(-1) ) and PNU-120596 (30 mg·kg(-1) ) significantly reduced mechanical hyperalgesia and weight-bearing deficits for up to 4 h. Compound B (30 mg·kg(-1) ) also attenuated both measures of pain-like behaviour, albeit less robustly. Whereas compound B and PNU-120596 attenuated the carrageenan-induced increase in levels of TNF-α and IL-6 within the hind paw oedema, diclofenac only attenuated IL-6 levels. Established mechanical hyperalgesia induced by carrageenan or CFA was also partially reversed by compound B and PNU-120596. However, diclofenac was considerably more efficacious. Formalin-induced nocifensive behaviours were only reversed by compound B, albeit at doses which disrupted motor performance.

CONCLUSIONS AND IMPLICATIONS

α7 nACh receptor PAMs could prove to be useful in the treatment of inflammatory pain conditions, which respond poorly to NSAIDs or in situations where NSAIDs are contra-indicated.

Treatment of mild to moderate Graves' ophthalmopathy with sodium diclofenac: a pilot study

OBJECTIVE

To report the use of sodium diclofenac, an antagonist of PPAR-gamma and cyclooxigenase-2 (COX-2) inhibitor in the treatment of mild to moderate Graves' ophthalmopathy.

SUBJECTS AND METHODS

Thirteen patients with clinical activity score (CAS) 2 to 7 were treated during a period ranging from 3 to 12 months (mean 7.8 ± 3.4) with oral sodium diclofenac, 50 mg every 12 hours.

RESULTS

Extra-ocular muscle restriction and CAS improved significantly, p = 0.003 and = 0.004, respectively. Ocular pain and diplopia disappeared, except for one patient who reported improvement of these symptoms. No recurrence was found after interruption of treatment.

CONCLUSIONS

Treatment of moderate Graves' ophthalmopathy with oral sodium diclofenac is a good, safe and less expensive therapeutic option. Like others new treatment trials, findings must be confirmed in a greater number of patients in a controlled study.

A novel injectable formulation of diclofenac compared with intravenous ketorolac or placebo for acute moderate-to-severe pain after abdominal or pelvic surgery: a multicenter, double-blind, randomized, multiple-dose study

BACKGROUND

Injectable formulations of diclofenac have long been available in Europe and other countries. These formulations use a default dose of 75 mg of diclofenac delivered IV over 30 to 120 minutes or as an IM injection. A novel formulation of injectable diclofenac sodium, Dyloject®, is solubilized with hydroxypropyl β-cyclodextrin (HPβCD) so that it can be given IV or IM in a small volume bolus. In this multicenter, multiple-dose, multiple-day, randomized, double-blind, parallel-group phase 3 study, we investigated whether lower doses of HPβCD diclofenac delivered as a small volume bolus would be effective for the management of acute pain after abdominal or pelvic surgery.

METHODS

Adults with moderate and severe pain, defined as ≥50 mm on a 0 to 100 mm visual analog scale, within 6 hours after surgery were randomly assigned (1:1:1:1 ratio) to receive HPβCD diclofenac, 18.75 mg or 37.5 mg; ketorolac tromethamine 30 mg; or placebo. Patients in all treatment arms received a bolus IV injection every 6 hours until discharged. They were observed for at least 48 h, and for up to 5 days. Rescue IV morphine was available any time, up to a total of 7.5 mg over a 3-hour period. The primary efficacy measure was the sum of pain intensity differences from 0 to 48 hours after study drug initiation.

RESULTS

Three hundred thirty-one patients received ≥1 dose of study drug. Over the first 48 hours, both IV HPβCD diclofenac doses, as well as ketorolac, produced significant reductions in pain intensity over placebo (all P < 0.05), as well as significant reductions in the need for rescue morphine administration. Both doses of HPβCD diclofenac, as well as ketorolac, significantly reduced rescue morphine dosages, as compared to placebo (P < 0.0001), and time to rescue morphine administration was significantly increased by treatment with 18.75 mg diclofenac and ketorolac. The overall incidence of treatment-related adverse events was 20.2%. No treatment-related serious adverse events were reported in either diclofenac dose group, whereas only 1 was reported in the ketorolac group.

CONCLUSIONS

For patients with acute moderate and severe pain after abdominal or pelvic surgery, repeated 18.75 mg and 37.5 mg doses of HPβCD diclofenac provided significant analgesic efficacy, as compared to placebo. Significant analgesic efficacy was also provided by the active comparator ketorolac. Both HPβCD diclofenac and ketorolac significantly reduced the need for opioids.

An assessment of the efficacy and safety of diclofenac potassium liquid-filled capsules in patients with various levels of baseline pain intensity

CONTEXT

Diclofenac potassium liquid-filled soft gelatin capsule (DPSGC; Zipsor*) is a novel formulation of diclofenac potassium used to treat mild to moderate acute pain.

OBJECTIVE

To investigate whether DPSGC 25 mg provided significant reduction in pain intensity compared with placebo, regardless of baseline pain intensity, a post hoc analysis was performed of pooled data from two replicate randomized controlled trials (NCT00366444 and NCT00375934) that evaluated the safety and efficacy of DPSGC in postbunionectomy treatment.

METHODS

Patients from the two randomized trials were assigned to one of two subgroups: patients with baseline numerical pain rating scale (NPRS) scores of 4 or greater to less than 7 and those with baseline NPRS scores of 7 or greater. Within each subgroup, efficacy and safety of DPSGC was compared with placebo.

RESULTS

Across the two studies, 73 DPSGC- and 59 placebo-treated patients had baseline pain intensity scores ranging from 4 or greater to less than 7, while 128 DPSGC- and 141 placebo-treated patients had baseline pain intensity scores of 7 or greater. Significantly lower mean 48-hour NPRS scores were observed in the DPSGC group, regardless of baseline pain intensity (P < 0.0001). In both subgroups, at least twice as many patients treated with DPSGC rated the study drug as very good or excellent compared with patients taking placebo. Potential limitations for this post hoc analysis include study design and patient population. As with all studies investigating treatment for pain, the use of rescue medication may also be a potential limitation.

CONCLUSIONS

DPSGC provided significantly greater improvements in pain compared with placebo following bunionectomy, regardless of patients' baseline pain level.

A comparison of the therapeutic efficacy of diclofenac in osteoarthritis: a systematic review of randomised controlled trials

OBJECTIVE

Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID) commonly prescribed for pain relief in osteoarthritis (OA). The relative efficacy of diclofenac compared to other pain relief medications used in OA (e.g., alternative NSAIDs, cyclooxygenase type 2 [COX-2] inhibitors) is uncertain. The objective of this systematic review is to compare the current evidence on efficacy of diclofenac versus other pain relief medications.

RESEARCH DESIGN AND METHODS

A systematic literature search was carried out for randomised, well controlled clinical trials comparing the efficacy of diclofenac with other pain relief medications in OA (reviews, meta-analyses and n = 1 trials were excluded). The databases searched were EMBASE, Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, and Ovid MEDLINE Daily Update. Articles were included from 1999 onwards. Retrieved articles were discussed by comparator medication.

RESULTS

Of the 263 articles identified in the literature search, 37 were eventually included in this review. These were comparisons with the selective COX-2 inhibitors etoricoxib, celecoxib, lumiracoxib and rofecoxib; comparisons with the NSAIDs aceclofenac, dexketoprofen, etodolac, lornoxicam, meloxicam, nabumetone and nimesulide; and comparisons to acetaminophen, tramadol, diacerein, oxaceprol, oral hydrolytic enzyme therapies, Chinese herbal remedies and castor oil supplementation. Overall, in the majority of the trials at therapeutic doses diclofenac provided similar efficacy to comparator treatments; and in general diclofenac was able to support its position as a reference medication of choice for OA trials.

CONCLUSIONS

The efficacy of diclofenac is largely unchallenged in that it remains as effective as newer pain relief medications employed in OA. A review of the available data demonstrates that diclofenac continues to provide physicians with a benchmark pharmacological treatment for OA.

Risk of anastomotic leakage with use of NSAIDs after gastrointestinal surgery

PURPOSE

Analgesic regimes to avoid opioid-related adverse effects have been recommended in gastrointestinal surgery. Non-steroidal anti-inflammatory drugs (NSAIDs) are an important component of opioid sparing regimes in that these drugs indirectly reduce pain by inhibiting inflammation. Although beneficial for most surgical patients, animal studies and recent clinical studies suggest a harmful effect on new intestinal anastomoses by increasing the rate of leakage. NSAIDs may indirectly disturb anastomotic healing by inhibiting inflammation as an integrated part of the wound healing process in an early, critical phase after surgery.

METHODS

A literature review based on a structured search in PubMed of clinical and experimental studies investigating the effects of NSAIDs on anastomotic healing and leakage rates after intestinal surgery, as well as proposed mechanisms and effects studied in animal models.

RESULTS

Three recent observational cohort studies (accumulated n = 882) indicate an increased rate of anastomotic leakages (15-21%) associated with cyclooxygenase-2 (COX-2) selective NSAIDs after intestinal surgery compared to the leakage rates in controls or historical cohorts (1-4%). Three prospective studies on related topics contain relevant data on NSAIDs and are compared to these studies. Several experimental animal studies support an increased risk for anastomotic leakage with the use of NSAIDs.

CONCLUSION

The reported effects of NSAIDs on anastomotic healing suggest an increased risk for leakage. A better understanding of the complex interactions of NSAID-induced inhibition on anastomotic healing is a prerequisite for the safe use of NSAIDs. Until more data are available, a careful use of NSAIDs may be warranted in gastrointestinal anastomotic surgery.

Onset of action of diclofenac potassium liquid-filled capsules in dental surgery patients

OBJECTIVE

Diclofenac potassium soft gelatin capsules (DPSGC) are a low-dose, liquid-filled formulation that uses patented dispersion technology to facilitate rapid and consistent gastrointestinal absorption. Onset of pain relief experienced by patients receiving DPSGC was evaluated in two dental pain studies. Confirmed perceptible pain relief was evaluated in a post hoc analysis from these randomized controlled trials.

RESEARCH DESIGN AND METHODS

Adult patients (n = 514) were enrolled in two multicenter, parallel group, double-blind, placebo-controlled studies. Patients undergoing third molar extraction and experiencing a requisite level of pain (≥50 mm on a 100-mm visual analog scale within 4 hours post-surgery) were randomized to receive single doses of DPSGC 25 mg, 50 mg, 100 mg, or placebo. Pain was assessed at baseline and during 6 hours after dosing. Times to onset of perceptible and meaningful pain relief were recorded using the two-stopwatch method. Confirmed perceptible pain relief was determined in the DPSGC and placebo groups by calculating the median time to onset of perceptible pain relief (first stopwatch) in only those individuals who reported meaningful pain relief (second stopwatch).

RESULTS

More than 80% of patients achieved confirmed perceptible pain relief in the DPSGC groups compared with less than 30% of patients in the placebo group (Study 1 and Study 2, p < 0.0001). The median time to onset of confirmed perceptible pain relief in the two studies was less than 30 minutes for patients receiving any dose of DPSGC and more than 360 minutes in the placebo group (Study 1 and Study 2, p < 0.0001). DPSGC was well tolerated and no serious adverse events were reported. Study design limitations include the short duration of the trial and evaluation of a relatively limited patient population.

CONCLUSIONS

These results indicate that DPSGC was efficacious in providing a rapid onset of confirmed perceptible pain relief within 30 minutes of administration in these single dose postoperative dental pain studies.

Effects of the pharmaceuticals gemfibrozil and diclofenac on the marine mussel (Mytilus spp.) and their comparison with standardized toxicity tests

Human pharmaceuticals, like the lipid lowering agent gemfibrozil and the non-steroidal anti-inflammatory drug diclofenac are causing environmental concern. In this study, the marine mussel (Mytilus spp.) was exposed by injection to environmentally relevant and elevated (1 μg/L and 1000 μg/L) concentrations of both compounds and biomarker expression was observed. Gemfibrozil exposure induced biomarkers of stress (glutathione S-transferase and metallothionein) at both concentrations 24h and 96 h after exposure, respectively. Biomarkers of damage (lipid peroxidation (LPO) and DNA damage) were significantly affected, as well as the biomarker for reproduction, alkali-labile phosphate assay, indicating the potential oxidative stress and endocrine disrupting effect of gemfibrozil. Diclofenac significantly induced LPO after 96 h indicating tissue damage. Additionally standard toxicity tests using the marine species Vibrio fischeri, Skeletonema costatum and Tisbe battagliai showed differences in sensitivity to both drugs in the mg/L range. Results indicate a suite of tests should be used to give accurate information for regulation.

The outpatient utilization of non-steroidal anti-inflammatory drugs in South Bačka District, Serbia

OBJECTIVE

To evaluate the utilization of non-steroidal anti-inflammatory drugs (NSAIDs) in South Bačka District (SBD), Serbia.

SETTING

State-owned and private pharmacies in SBD, a northern district of Serbia, with 605,720 inhabitants (according to the 2008 census).

METHOD

Data on the number of packages, size of packages, and retail price of NSAIDs (Anatomical Therapeutic Chemical (ATC) group M01A) from 1 January to 31 March 2008 were obtained from all state-owned and private pharmacies in SBD. This included NSAIDs bought without prescription and those issued by prescription (on the Health Insurance Companies List for Reimbursement). The number of defined daily doses/1000 inhabitants/day (DDD/1000 inh/day) was calculated. Within the DU90% (drug utilization 90%) segment, the proportion of high-, medium- and low-risk NSAIDs with respect to the risk of gastrointestinal (GI) bleeding was determined. Price/DDD was also calculated.

MAIN OUTCOME MEASURE

Consumption of drugs expressed as DDD/1000 inh/day.

RESULTS

The total consumption of NSAIDs over a 3-month period was 48.31 DDD/1000 inh/day. Only four drugs were within DU90%: diclofenac, ibuprofen, nimesulide and meloxicam (62.14, 19.87, 5.77, and 5.73% of total NSAID consumption, respectively). All dispensed NSAIDs within the DU90% segment except nimesulide (which was exclusively purchased without prescription) were nearly equally purchased without prescription and issued by prescription. The average price per DDD within the DU90% segment was 0.17 Euro/DDD, whereas it was 0.30 Euro/DDD for NSAIDs beyond the DU90% segment. The pattern of use of NSAIDs according to their GI risk showed that medium-risk diclofenac accounted for 66.45%, whereas low-risk ibuprofen was estimated to be 21.25% within the DU90% segment.

CONCLUSION

Factors other than evidence-based medicine (such as poor health education in the past that led to long-lasting consequences on the cultural behaviour of the general population as well as on the prescribing habits of physicians) have a dominating impact on the use of NSAIDs in SBD. Targeted education from independent sources in the prescribing, dispensing and use of drugs is required to improve the quality of prescription and use of NSAIDs in Serbia.