Metamizole: A Review Profile of a Well-Known “Forgotten” Drug. Part II: Clinical Profile

Pain in Colorectal Surgery: How Does It Occur and What Tools Do We Have for Treatment?

Pain is a complex entity with deleterious effects on the entire organism. Poorly controlled postoperative pain impacts the patient outcome, being associated with increased morbidity, inadequate quality of life and functional recovery. In the current surgical environment with less invasive surgical procedures increasingly being used and a trend towards rapid discharge home after surgery, we need to continuously re-evaluate analgesic strategies. We have performed a narrative review consisting of a description of the acute surgical pain anatomic pathways and the connection between pain and the surgical stress response followed by reviewing methods of multimodal analgesia in colorectal surgery found in recent literature data. We have described various regional analgesia techniques and drugs effective in pain treatment, emphasizing their advantages and concerns. We have also tried to identify present knowledge gaps requiring future research. Our review concludes that surgical pain has peculiarities that make its management complex, implying a consistent, multimodal approach aiming to block both peripheral and central pain pathways.

Case Report: Simultaneously Induced Neutropenia and Hemolysis After a Single Metamizole Dose

BACKGROUND AND OBJECTIVE

Metamizole is a non-opioid ampyrone sulfonate compound with potent analgesic, antipyretic, and spasmolytic effects. Agranulocytosis is a rare life-threatening complication of metamizole.

CASE

Here, we present the case of a 62-year-old patient who developed agranulocytosis as well as hemolysis after a single administration of metamizole.

CONCLUSION

This case illustrates the inherent allergic potential of metamizole and its effects on different hematopoietic cell types.

Pyrazolone-type compounds (part II): in vitro and in silico evaluation of antioxidant potential; structure-activity relationship

The pyrazolone class comprises a variety of hybrid compounds displaying diverse biological actions. Although studied for decades, these compounds are still of interest due to their facile chemical transformations. In our previous work, we presented the synthetic route of functionalised pyrazolone derivatives. The presence of pyrazolone structural motif in many drugs, such as edaravone, prompted us to investigate the antioxidant features of the selected compounds. In this paper, we provide an extensive in vitro and in silico description of the antioxidant properties of selected pyrazolone analogues. The obtained in vitro results revealed their great antiradical potency against the DPPH radical (IC₅₀ values in the 2.6-7.8 μM range), where the best results were obtained for analogues bearing a catechol moiety. Density functional theory (DFT) was used to assess their antioxidant capacity from the thermodynamic aspect. Here, good agreement with in vitro results was achieved. DFT was employed for the prediction of the most preferable radical scavenging pathway, also. In polar solvents, the SPLET mechanism is a favourable scavenging route, whereas in nonpolar solvents the HAT is slightly predominant. Furthermore, antioxidant mechanisms were studied in the presence of relevant reactive oxygen species. The obtained values of the reaction enthalpies with the selected radicals revealed that HAT is slightly prevailing in polar solvents, while the SPLET mechanism is dominant in nonpolar solvents. Regarding the well-known antioxidant features of the drug edaravone, these findings represent valuable data for this pyrazolone class and could be used as the basis for further investigations.

Pain Management and Analgesics Used in Small Mammals during Post-Operative Period with an Emphasis on Metamizole (Dipyrone) as an Alternative Medication

Metamizole (dipyrone) is a widely used non-opioid analgesic in both human and animal medicine. Metamizole's safety has been the topic of numerous opposing debates, given the fact that in certain countries metamizole is frequently used as an over-the-counter (OTC) medicine, while in others it is banned due to the risk of agranulocytosis. Further, small mammals such as rabbits, ferrets, rodents, and hedgehogs have become some of the most common pets present in veterinary practice, and each of these species has specific analgesic needs due to their anatomy and physiology. The key to providing appropriate medical care is in finding a substance that has minimal negative effects. In small mammals, analgesia is an important factor and, it happens frequently that, pain in these patients is not well managed. Post-operative pain management is an important topic in the welfare of animals. The objectives of this review, thus, were to provide a concise overview of analgesics that are used in the treatment of postoperative pain in small mammals (e.g., rabbits and rodents) and to highlight the importance of this product, metamizole, in veterinary medicine, as well as the potential of this substance as an alternative analgesic for the treatment of postoperative pain in small mammals.

Pharmaceutical care for patients with headache

INTRODUCTION

Headache cephalalgia is the condition in which individuals feel pain in different parts of the head. It is one of the most common disorders believed to be amenable to self-treatment. The pharmacist can provide significant support to patients.

Nonopioid analgesics for analgesia in critically ill patients: Friends, enemies, or collaborators

Patients in intensive care units (ICUs) experience pain, which they describe as a significant cause of stress during treatment. It can progress to chronic pain and significantly affect the quality of life. Opioids have long been the backbone of ICU pain therapy. The consequences of their long-term use are known today, such as prolonged ICU stay and mechanical ventilation, resulting in increased treatment costs. Additionally, abstinence syndrome is a consequence of abrupt opioid withdrawal. Also, there is a risk of tolerance and hyperalgesia after prolonged opioid use. Globally, opioid dependence after hospital opioid treatment is alarming, although there is still a lack of data on its incidence after ICU. Multimodal analgesia enables comfort to the patient, opioid-sparing, and avoidance of side effects of non-opioid analgesics. Nonsteroidal anti-inflammatory drugs (NSAIDs) are a broad group of drugs recommended with paracetamol to treat mild to moderate acute postoperative pain. Although often prescribed by intensivists, their use in treating painful conditions in ICU is controversial due to the possible consequences on the organs of critically ill patients. Due to the inhibition of cyclooxygenases, NSAIDs indirectly cause vasoconstriction of the renal arteries and arterioles, leading to kidney damage. NSAIDs inhibit platelet aggregation and may predispose to bleeding. Analgesia of a critically ill patient is a important part of their treatment, however it can be challenging in certain patients. Numerous combinations of pharmacological and non-pharmacological approaches can be adapted to the patient's current characteristics.

Oxidative damage of canine erythrocytes after treatment with non-steroidal anti-inflammatory drugs

OBJECTIVE

To investigate oxidative erythrocyte damage in dogs treated with different non-steroidal anti-inflammatory drugs.

MATERIAL AND METHODS

Case-controlled prospective observational study using blood obtained from dogs presenting for lameness examinations or standard surgical procedures to a private referral clinic. Sampling was performed from April 2018 to July 2019. Groups comprised dogs receiving either metamizole (dipyrone) (22 dogs), carprofen (20 dogs) or meloxicam (20 dogs) for a minimum of 10 days. Dogs with gastrointestinal hemorrhage were excluded from the study. A complete hematological, as well as a basic biochemical profile were performed in every dog. Pappenheim stained blood smears were evaluated for eccentrocytes and brilliant cresyl blue stained smears for Heinz bodies. EDTA blood was frozen at -80°C immediately after sampling for measurement of superoxide dismutase and gluthathione peroxidase activity at an external laboratory. Hemoglobin concentration, superoxide dismutase and gluthathione peroxidase activities, reticulocyte count, eccentrocyte and Heinz body numbers were determined prospectively as key parameters for further statistical assessment with Kruskal-Wallis test and Dunn's multiple comparisons test.

RESULTS

Dogs receiving metamizole showed a significant increase in eccentrocyte (median 14.5/500 cells vs. 0/500 cells in the other groups, p < 0.0001) and reticulocyte number (median 191.4 × 10⁹/l vs. 31.6-37.9 × 10⁹/l, p < 0.0001) and a significant decrease in hemoglobin concentration (median 8.4 mmol/l vs. 10.1-10.5 mmol/l, p < 0.0003). No significant difference in superoxide dismutase and gluthathione peroxidase activities was observed between dogs receiving metamizole and the other groups. Heinz bodies were not found in any of the dogs.

CONCLUSION

Treatment with metamizole for 10 or more days resulted in decreased hemoglobin concentration, eccentrocytosis and reticulocytosis in dogs in this study. This might be a sign of increased oxidative damage caused by this drug.

CLINICAL SIGNIFICANCE

Prolonged metamizole therapy should be evaluated critically in patients already affected by severe illness or underlying anaemia.

Pharmacokinetic Profiles of Metamizole Metabolites after Intramuscular and Intravenous Administration in Healthy Arabian Horses

Metamizole sodium (MT) is an analgesic and antipyretic drug molecule used in humans, horses, cattle, swine, and dogs. Metamizole rapidly hydrolyzes and turns into methylamino antipyrine (MAA), an active primary metabolite of MT. The present study aims to determine the pharmacokinetic (PK) profiles of MT metabolites after intravenous (IV) and intramuscular (IM) administration into sex of Arabian horses (Equus ferus caballus) using a cross-over study design. The plasma samples were extracted by solid-phase extraction (SPE) method, and plasma concentrations of MT metabolites were analyzed by high-performance liquid chromatography (HPLC). After administrations of MT, plasma concentrations of methylamino antipyrine (MAA), amino antipyrone (AA), and acetylamino antipyrone (AAA) were determined within range of 15 min-12 h. Plasma concentrations of AA and AAA were lower than the plasma concentrations of major metabolite MAA at each sampling point. The PK parameters were statistically evaluated for MT's metabolites between male and female horses and also between IM and IV administrations of PK parameters such as C_max , t_max , t_1/2λz , AUC_0-t , AUC_0-∞ , λz, Cl and V_ss (p < .05). The AUC_IM /AUC_IV ratio in female and male horses for MAA was 1.19 and 1.13, respectively. The AUC_IM /AUC_IV ratio for AA was lower than those found for MAA. AUC_IM /AUC_IV ratio was statistically significantly different between male and female horses for AA (p < .05). According to these results, some PK parameters such as Cmax, AUC, and MRT, MAA and AA concentrations have shown statistically significant differences by MT administrations.

A possible increased risk of metamizole-associated neutropenia among COVID-19 patients

Metamizole is commonly used as analgesic and antipyretic drug. The use of metamizole is prohibited in several countries due to its rare side effect of neutropenia and even agranulocytosis. Among the many symptoms of COVID-19, fever and diffuse pain predominant and therefore it can be assumed that metamizole may be widely used in the current epidemic period. So far, there have been no reports on the safety of metamizole in COVID-19 patients. We describe a series of 3 patients who developed severe neutropenia under metamizole treatment, raising a concern of a possible increased risk of this side effect among COVID-19 patients.

Prevalence and Factors Associated with Analgesic Prescribing in Poly-Medicated Elderly Patients

BACKGROUND

Pain is common in older patients and management guidelines rarely consider the effect of multiple comorbidities and concurrent medications on analgesic selection.

OBJECTIVES

The objectives of this study were to identify the prevalence and pattern of analgesic prescribing and associated factors in older patients with polypharmacy.

METHODS

Older patients (aged ≥ 75 years) admitted to the Royal Adelaide Hospital between September 2015 and August 2016 and with polypharmacy were included and their comorbidities and medications prescribed at discharge were recorded. Drug Burden Index and Charlson Comorbidity Index were calculated. The number of medications that increased the risk of orthostatic hypotension were recorded. Logistic regression was used to compute the association between analgesic use and participant characteristics, and results were presented as odds ratios and 95% confidence intervals, adjusted for age, sex, Charlson Comorbidity Index, Drug Burden Index and orthostatic hypotension.

RESULTS

Over 15,000 admissions were identified, of which 1192 patients were included, 824 (69%) of whom were prescribed an analgesic medication. Paracetamol (used by 89% of analgesic users), opioids (34%) and adjuvants (17%) were used more frequently than non-steroidal anti-inflammatory drugs (8%). Analgesic users had a higher Drug Burden Index, were prescribed more medications and were less likely to be male compared with non-users. Charlson Comorbidity Index across the cohort was high (7.3 ± 1.9) but there was no difference between analgesic users and non-users, but analgesic users were more likely to have a documented diagnosis of osteoarthritis, osteoporosis and falls. Opioid use was associated with the Drug Burden Index, while adjuvant use was associated with orthostatic hypotension. Opioid use was associated with having a diagnosis of osteoporosis and falls.

CONCLUSIONS

In our cohort of poly-medicated elderly patients, prescription of analgesic medications was common, and these patients are likely to have an increased rate of adverse drug reactions and falls compared with those who were not prescribed analgesic medications.

Metamizole but not ibuprofen reduces the plasma concentration of sertraline: Implications for the concurrent treatment of pain and depression/anxiety disorders

AIM

Comorbidity of pain and depression or anxiety is a challenging clinical phenomenon, often requiring the concurrent application of antidepressant and analgesic drugs. Growing evidence suggests that the analgesic metamizole exhibits cytochrome P450 inducing properties. In the present study, we assessed the impact of metamizole and ibuprofen on plasma concentrations of the selective serotonin reuptake inhibitor sertraline.

METHODS

Out of a therapeutic drug monitoring (TDM) database, three groups of patients were compared: patients receiving sertraline and metamizole (n = 15), patients receiving sertraline and ibuprofen (n = 19), and a matched control group without one of the analgesics (n = 19).

RESULTS

Metamizole was associated with 67% lower median sertraline plasma concentrations compared to the control group (14 vs 42 ng/mL, P < 0.001). In contrast, differences between the ibuprofen group and the control group did not reach statistical significance (31 vs 42 ng/mL, P = 0.128). Moreover, the metamizole group demonstrated lower dose-adjusted drug concentrations than the ibuprofen group (0.10 vs 0.26 (ng/mL)/(mg/day), P = 0.008). Finally, the metamizole group exhibited a higher proportion of patients whose sertraline concentrations were below the therapeutic reference range (40% in the metamizole group, 5% in the ibuprofen group, 0% in the control group, P = 0.005) indicating therapeutically insufficient drug concentrations.

CONCLUSION

Our findings support preliminary evidence that metamizole acts as a potent inductor of cytochrome P450 isoenzymes CYP2B6 and CYP3A4. We observed a clinically meaningful pharmacokinetic interaction between metamizole and sertraline, leading to insufficiently low sertraline drug concentrations. Clinicians should therefore consider alternative drug combinations or apply TDM-guided dose adjustment of sertraline.

Evaluation of postoperative pain and toxicological aspects of the use of dipyrone and tramadol in cats

OBJECTIVES

The aim of this study was to evaluate the effects of dipyrone and tramadol, used for 5 days, on postoperative pain, hematological and biochemical parameters, and oxidative markers on erythrocytes.

METHODS

Twenty-eight healthy cats underwent ovariohysterectomy and were randomly allocated to four groups (each n = 7), according to the postoperative treatment administered intravenously: control (saline 1 ml q8h), DIP1 (dipyrone 25 mg/kg q24h), DIP2 (dipyrone 25 mg/kg q12h) and DIP3 (dipyrone 25 mg/kg q8h). All animals received tramadol (2 mg/kg q8h). Pain was assessed by visual analog (VAS), multidimensional UNESP and Glasgow pain scales for cats preoperatively and at 3, 6, 12, 24, 36 and 48 h after extubation. Venous blood was collected daily for 5 days, and on day 10, to perform a complete blood count (CBC) and determine the percentage of Heinz bodies (HBs). Serum biochemistry was evaluated preoperatively and on days 5 and 10; superoxide dismutase (SOD), catalase (CAT), myeloperoxidase (MPO) and lipoperoxidation were evaluated preoperatively and on days 3, 5 and 10.

RESULTS

Control cats had higher pain scores than DIP3 cats by UNESP (P = 0.0065), and DIP2 (P = 0.0035) and DIP3 cats (P = 0.0108) by VAS 3 h postoperatively. Rescue analgesia was required by two animals in the control group and one each in the DIP1 and DIP2 groups. There was no difference in SOD or CAT among groups. On day 5, MPO was more active in DIP2 than in DIP3 cats (P = 0.0274). No difference in lipoperoxidation among treatment and control cats was found. CBC remained constant and without statistical difference among groups. Control, DIP2 and DIP3 cats presented a similar percentage of HBs on day 10. Biochemical variables were similar among groups and times.

CONCLUSIONS AND RELEVANCE

The administration of dipyrone in cats, when used in combination with tramadol, did not ensure better analgesia than tramadol alone. Dipyrone did not significantly affect biochemical variables and oxidative markers, despite minimal, clinically irrelevant, hematological differences between groups.

Computational Analysis of Dipyrone Metabolite 4-Aminoantipyrine As A Cannabinoid Receptor 1 Agonist

BACKGROUND

Cannabinoid receptor 1 has its crystallographic structure available in complex with agonists and inverse agonists, which paved the way to establish an understanding of the structural basis of interactions with ligands. Dipyrone is a prodrug with analgesic capabilities and is widely used in some countries. Recently some evidence of a dipyrone metabolite acting over the Cannabinoid Receptor 1has been shown.

OBJECTIVE

Our goal here is to explore the dipyrone metabolite 4-aminoantipyrine as a Cannabinoid Receptor 1 agonist, reviewing dipyrone characteristics, and investigating the structural basis for its interaction with the Cannabinoid Receptor 1.

METHOD

We reviewed here recent functional studies related to the dipyrone metabolite focusing on its action as a Cannabinoid Receptor 1 agonist. We also analyzed protein-ligand interactions for this complex obtained through docking simulations against the crystallographic structure of the Cannabinoid Receptor 1.

RESULTS

Analysis of the crystallographic structure and docking simulations revealed that most of the interactions present in the docked pose were also present in the crystallographic structure of Cannabinoid Receptor 1 and agonist.

CONCLUSION

Analysis of the complex of 4-aminoantipyrine and Cannabinoid Receptor 1 revealed the pivotal role played by residues Phe 170, Phe 174, Phe 177, Phe 189, Leu 193, Val 196, and Phe 379, besides the conserved hydrogen bond at Ser 383. The mechanistic analysis and the present computational study suggest that the dipyrone metabolite 4-aminoantipyrine interacts with the Cannabinoid Receptor 1.

Systematic review and meta-analysis on non-opioid analgesics in palliative medicine

Non-opioid analgesics are widely used for pain relief in palliative medicine. However, there is a lack of evidence-based recommendations addressing the efficacy, tolerability, and safety of non-opioids in this field. A comprehensive systematic review and meta-analysis on current evidence can provide a basis for sound recommendations in clinical practice. A database search for controlled trials on the use of non-opioids in adult palliative patients was performed in Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PsycINFO, and EMBASE from inception to 18 February 2018. Endpoints were pain intensity, opioid-sparing effects, safety, and quality of life. Studies with similar patients, interventions, and outcomes were included in the meta-analyses. Our systematic search was able to only identify studies dealing with cancer pain. Of 5991 retrieved studies, 43 could be included (n = 2925 patients). There was no convincing evidence for satisfactory pain relief by acetaminophen alone or in combination with strong opioids. We found substantial evidence of moderate quality for a satisfactory pain relief in cancer by non-steroidal anti-inflammatory drugs (NSAIDs), flupirtine, and dipyrone compared with placebo or other analgesics. There was no evidence for a superiority of one specific non-opioid. There was moderate quality of evidence for a similar pain reduction by NSAIDs in the usual dosage range compared with up to 15 mg of morphine or opioids of equianalgesic potency. The combination of NSAID and step III opioids showed a beneficial effect, without a decreased tolerability. There is scarce evidence concerning the combination of NSAIDs with weak opioids. There are no randomized-controlled studies on the use of non-opioids in a wide range of end-stage diseases except for cancer. Non-steroidal anti-inflammatory drugs, flupirtine, and dipyrone can be recommended for the treatment of cancer pain either alone or in combination with strong opioids. The use of acetaminophen in the palliative setting cannot be recommended. Studies are not available for long-term use. There is a lack of evidence regarding pain treatment by non-opioids in specific cancer entities.

Genetic Basis of Delayed Hypersensitivity Reactions to Drugs in Jewish and Arab Populations

Genetic variation can affect drug pharmacokinetics and pharmacodynamics and contribute to variability between individuals in response to medications. Specifically, differences in allele frequencies among individuals and ethnic groups have been associated with variation in their propensity to develop drug hypersensitivity reactions (HSRs). This article reviews the current knowledge on the genetic background of HSRs and its relevance to Jewish and Arab populations. The focus is on human leukocyte antigen (HLA) alleles and haplotypes as predictive markers of HSRs ("immunopharmacogenetics"), but other genes and alleles are described as well. Also discussed is the translation of the pharmacogenetic information to practice recommendations.

Metamizole Utilization and Expenditure During 6-Year Period: Serbia vs. Croatia

Background: Metamizole is a medication with analgesic, antipyretic, spasmolytic, and weak anti-inflammatory effects. The aim of our study was to evaluate a six-year trend in the utilization and expenditure of metamizole in comparison to other group of licensed non-opioid analgesics in Serbia and Croatia, in order to rationalize its use and prescribing in these countries.

Methods: The data of metamizole vs. all other non-opioid analgesics utilization and expenditure in Serbia and Croatia was analyzed according to the WHO methodology and expressed as defined daily doses per 1,000 inhabitants per day (DDD/1,000 inhabitants/per day) and total costs, respectively, during the 6-year period from 2010 to 2015.

Results: In the observed period, utilization of metamizole was 3.31 fold higher in Serbia than in Croatia (median in Serbia was 2.238 vs. 0.675 in Croatia DDD/1,000 inhabitants/per day/per year). Expenditure of metamizole in the same period was 5.29-fold higher in Serbia than in Croatia (median in Serbia was 1,738,192.51 €/per year vs. 328,355.03 €/per year in Croatia).

Conclusion: Utilization and expenditure of non-opioid analgesics, including metamizole, in Serbia was significantly higher comparing with Croatia.Further research is needed to determine whether the current analgesic consumption in Serbia meets the needs of the patient. The benefits of metamizole should be weighed against the risk of metamizole-induced adverse effects. Until then, its prescribing should be based on indications and the appropriate duration of therapy.

Single dose dipyrone (metamizole) for acute postoperative pain in adults

BACKGROUND

Dipyrone (metamizole) is a nonsteroidal anti-inflammatory drug used in some countries to treat pain (postoperative, colic, cancer, and migraine); it is banned in other countries because of an association with life-threatening blood disorders. This review replaces a 2010 Cochrane review that has been withdrawn.

OBJECTIVES

To assess the analgesic efficacy and associated adverse events of single dose dipyrone for moderate to severe acute postoperative pain using methods that permit comparison with other analgesics evaluated in standardised trials using almost identical methods and outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and LILACS to 11 August 2015; the Oxford Pain Relief Database; two clinical trial registries; and the reference lists of articles.

SELECTION CRITERIA

We included randomised, double-blind, placebo-controlled trials of single dose dipyrone for relief of established moderate to severe postoperative pain in adults. We accepted oral, rectal, intramuscular, and intravenous routes of administration.

DATA COLLECTION AND ANALYSIS

Two review authors independently considered studies for inclusion in the review, assessed risk of bias, and extracted data. We used summed total pain relief or pain intensity difference (TOTPAR or SPID) over four to six hours to calculate the number of participants achieving at least 50% pain relief. From derived results, we calculated the risk ratio and number needed to treat for an additional beneficial outcome (NNT), with 95% confidence intervals (CI), for one participant to experience at least 50% pain relief over four to six hours compared to placebo. We looked at use of rescue medication and time to use of rescue medication as additional measures of efficacy. We also looked for information on adverse events and withdrawals.

MAIN RESULTS

We included eight studies, involving 809 participants, comparing oral dipyrone 500 mg (143 participants), oral dipyrone 1000 mg (57 participants), and intramuscular dipyrone 2000 mg (35 participants) with placebo (236 participants). In addition to placebo, all studies used active controls (ibuprofen, paracetamol, aspirin, flurbiprofen, ketoprofen; 338 participants). Seven studies used the oral route of administration, and one study used the intramuscular route. The mean age ranged from 23 to 62 years. Six studies included both men and women, and two studies included only women. All the studies were small, but were otherwise of moderate to good quality.Over 70% of participants experienced our primary outcome of at least 50% pain relief over four to six hours with oral dipyrone 500 mg compared to 30% with placebo (five studies, 288 participants; NNT 2.4 (95% CI 1.8 to 3.1)) (moderate quality evidence). There were insufficient data to assess other doses or routes of administration of dipyrone.Fewer participants needed rescue medication within four to six hours with dipyrone 500 mg than with placebo (7% with dipyrone versus 34% with placebo; four studies, 248 participants) (low quality evidence).The data on numbers of participants experiencing any adverse event was inconsistently reported and no analysis was possible. No serious adverse events or adverse event withdrawals were reported (very low quality evidence).There were too few data to compare dipyrone directly with other active treatments.

AUTHORS' CONCLUSIONS

Based on very limited information, a single dose of dipyrone 500 mg provides good pain relief to about 70% of people treated, compared to about 30% with placebo. For every five people given dipyrone 500 mg, two people would experience this level of pain relief over four to six hours who would not have done with placebo, and fewer people would need rescue medication.We were unable to compare dipyrone directly with other active treatments, or to assess the effects of different doses or routes of administration, or the number of participants experiencing adverse events, because of insufficient data and inadequate reporting.

[Septic shock secondary to non-congenital chikungunya fever in a young infant: A clinical case]

INTRODUCTION

A chikungunya outbreak took place in the State of Yucatan starting in the second half of 2015 OBJECTIVE: To analyse the clinical course of a case of chikungunya in a previously healthy infant, providing practical evidence to guide future diagnoses and treatment during outbreak seasons in endemic areas

CASE REPORT

Clinical manifestation started with a sudden onset of fever and a diffuse macular-papillary erythema, originally treated in the community with non-steroidal anti-inflammatory drugs. Two days later, the fever relapsed with hypoactivity, severe thrombocytopenia and neutropenia (without lymphopenia), respiratory distress, liver dysfunction, sepsis, followed by septic shock with a fatal outcome. IgM test was positive to chikungunya, while her mother tested negative. Pseudomonas aeruginosa was isolated from the blood culture possible due to contamination, without ruling out the possibility of a mixed origin sepsis.

CONCLUSIONS

Chikungunya is a disease in which the manifestations in neonates and young infants can be severe, and even fatal. It is important to suspect it in this age group at risk of vector contact, in the presence of fever without apparent source of infection and cutaneous manifestations. It is important to use the antipyretics cautiously, considering the possibility of aggravating the underlying infection, and the potential hepatic and haematological damage.

Impairment of aspirin antiplatelet effects by non-opioid analgesic medication

Aspirin is the mainstay in prophylaxis of cardiovascular diseases. Impaired aspirin antiplatelet effects are associated with enhanced incidence of cardiovascular events. Comedication with non-opioid analgesic drugs has been described to interfere with aspirin, resulting in impaired aspirin antiplatelet effects. Additionally, non-opioid analgesic medication has been shown to enhance the risk of cardiovascular events and death. Pain is very frequent and many patients rely on analgesic drugs to control pain. Therefore effective analgesic options without increased risk of cardiovascular events are desirable. This review focuses on commonly used non-opioid analgesics, interactions with aspirin medication and impact on cardiovascular risk.

Older immigrants from the former Soviet Union and their use of complementary and alternative medicine

The population of older immigrants in the United States is growing and they bring their health beliefs and practices with them. Older immigrants from the former Soviet Union use a variety of complementary and alternative medicine (CAM) remedies which includes in part: 1) foods to which medicinal properties are attributed, 2) herbs, 3) external treatments, and 4) pharmaceuticals manufactured in the former Soviet Union and available over-the-counter. These remedies vary in their efficacy and are often used in combination with or in lieu of prescribed allopathic (Western) medications. Health beliefs regarding medicine in the United States has led older Slavic immigrant to distrust their US health care providers and system. Nurses are in a key position to inquire and work with older Slavic immigrants to safely use their CAM and provide more information about prescribed allopathic medications and the harmful effects of combining remedies without consultation.

Prevention of dipyrone (metamizole) induced inhibition of aspirin antiplatelet effects

We have recently shown that dipyrone (metamizole), a non-opioid analgesic, can nullify aspirin (acetylsalicylic acid; ASA) antiplatelet effects in patients with coronary artery disease (CAD). In this study, we analysed the aspirin and dipyrone drug-drug interaction in order to identify strategies to prevent the dipyrone induced inhibition of asprin antiplatelet effects. Platelet function was measured by arachidonic acid-induced light-transmission aggregometry, thromboxane (TX) B2- formation by immunoassay. Dipyrone metabolite plasma levels were determined by high-performance-liquid-chromatography (HPLC). In seven healthy individuals, in vitro ASA (30 µM/ 100 µM/ 300 µM/ 1,000 µM) and dipyrone (10 µM) coincubation revealed, that the aspirin and dipyrone interaction can be overcome by increasing doses of aspirin. In 36 aspirin and dipyrone comedicated CAD patients, addition of ASA (30 µM/ 100 µM) in vitro inhibited, but did not completely overcome the dipyrone induced reduction of aspirin antiplatelet effects. Notably, the inhibition of thromboxane formation in aspirin and dipyrone comedicated CAD patients coincided with dipyrone plasma levels. In a cross-over designed study in four healthy individuals, we were able to prove that inhibition of aspirin (100 mg/ day) effects by dipyrone (750 mg/ day) was reversible. Furthermore, aspirin (100 mg/ day) medication prior to dipyrone (750 mg/ day) intake prevented the inhibition of antiplatelet effects by dipyrone in 12 healthy individuals. In conclusion, aspirin medication prior to dipyrone intake preserves antiplatelet effects, circumventing the pharmacodynamic drug-drug interaction at the level of cyclooxygenase-1.