Fatal toxic myopathy attributed to propofol, methylprednisolone, and cyclosporine after prior exposure to colchicine and simvastatin

Muscular toxicity of colchicine combined with statins: a real-world study based on the FDA adverse event reporting system database from 2004-2023

Background

Through an analysis of the Food and Drug Administration Adverse Event Reporting System (FAERS), we explored the signal strength of adverse reactions (ADRs) related to myopathy caused by the combination of colchicine and statins and gained insight into the characteristics of these myopathy related ADRs.

Methods

We extracted data from the FAERS database about ADRs in individuals with myopathy resulting from the combination of colchicine and statins. The analysis was conducted for the period spanning from January 2004 to December 2023 using the reported odds ratio (ROR) and information component (IC) methods to assess muscle-related ADR signals.

Results

A total of 18,386 reports of statin myopathy-associated adverse reactions, 348 colchicine myopathy-associated adverse reactions, and 461 muscle-associated adverse reactions due to the combination of the two were collected; the strongest signals of statin myotoxicity events were for necrotizing myositis (ROR 50.47, 95% CL 41.74-61.01; IC 3.70 95% CL 3.25-4.08); the strongest signal for colchicine myotoxicity events was toxic myopathy (ROR 32.50, 95% CL 19.74-53.51; IC 4.97 95% CL 1.89-5.10), and the strongest signal for statins combined with colchicine was toxic myopathy (ROR 159.85, 95% CL 111.60-228.98; IC 7.22 95% CL 3.59-5.9); muscle-related adverse reactions signals were meaningful when the two drugs were combined in the order of colchicine combined with fluvastatin (ROR 187.38, 95% CL 96.68-363.17; IC 6.99 95% CL 1.65-5.68); colchicine combined with simvastatin in 135 cases (ROR 30.08. 95% CL 25.25-35.85; IC 4.80 95% CL 3.96-5.12); and colchicine combined with rosuvastatin (ROR 25.73, 95% CL 20.16-32.83; IC 4.59 95% CL 3.38-4.98) versus colchicine combined with atorvastatin (ROR 25.73, 95% CL 22.33-29.66; IC 4.59 95% CL 3.97-4.91) with almost identical signal intensity, followed by colchicine combined with pravastatin (ROR 13.67, 95% CL 9.17-20.37; IC 3.73 95% CL 1.87-4.47), whereas no signals were generated for lovastatin or pitavastatin.

Conclusion

Similar ADRs can occur when colchicine and statins are used individually or in combination; however, the strength of these reactions may differ. To minimize the risk of drug interactions, statins with less potential interactions, such as lovastatin, pitavastatin, and pravastatin, should be chosen, and myopathy-related indices and symptoms should be closely monitored during use.

CYP3A4/P-glycoprotein inhibitors related colchicine toxicity mimicking septic shock

Colchicine toxicity is uncommon when patients receive a therapeutic dose regularly. However, inadvertent drug interactions can result in unpredicted adverse outcomes. The toxicity of colchicine can manifest in various ways, ranging from mild and non-specific symptoms to severe form known as multiple organ dysfunction syndrome. This case highlights (1) the diagnostic challenge that arises when distinguishing between the severe manifestation of colchicine toxicity and septic shock and (2) concomitant prescription of colchicine with potent CYP3A4 and P-glycoprotein inhibitors (ie, clarithromycin) can lead to colchicine toxicity despite normal renal and hepatic clearance. Unfortunately, specific tests of colchicine toxicity were not routinely available. A high index of clinical suspicion and recognition of drug interactions with their common presentations are crucial for making diagnosis and management. Failure to recognise drug toxicity can result in poor outcomes.

Statin-Induced Rhabdomyolysis Associated With Transjugular Intrahepatic Portosystemic Shunt Placement

Rhabdomyolysis is a known rare and potentially lethal complication of statin use. This toxic effect is potentiated by alterations in hepatic physiology in patients with cirrhosis. Transjugular intrahepatic portosystemic shunt placement has the potential to further compound this effect; yet, examples of this have not previously been described in the literature. We present a case of a patient who experienced statin-induced rhabdomyolysis likely as a direct consequence of transjugular intrahepatic portosystemic shunt placement.

A systematic review of the drug-drug interaction between statins and colchicine: Patient characteristics, etiologies, and clinical management strategies

Colchicine and statins are frequently co-prescribed for prevention and treatment of cardiovascular diseases, auto-inflammatory diseases, and gout. Both are substrates and inhibitors of the cytochrome P-450 (CYP) 3A4 isozyme and P-glycoprotein so that taken together, they represent a clinically significant interaction. Data suggest the interaction may be associated with potentially life-threatening myopathies and rhabdomyolysis. The purposes of this systematic review (SR) were to gather and appraise evidence surrounding the statin-colchicine drug interaction and discuss related risk-mitigation strategies. An electronic literature search was performed. Twenty-one articles met the protocol to be included in the qualitative analysis: 18 case reports/series, 2 retrospective observational cohort studies, and 1 retrospective case-control study. Thirty-eight patients developed an adverse drug event (ADE) receiving statin-colchicine combination therapy; 25 (66%) patients developed myopathy; 10 (26%) patients developed rhabdomyolysis, and three (8%) patients developed neuromyopathy. Over 70% of patients developed ADEs on simvastatin or atorvastatin, and 80% of studies reported moderate-to-high intensity statins. Colchicine dosing varied but ranged between 0.5 to 1.5 mg daily. Sixty-two percent of patients in the case reports/series had comorbid renal disease. Seven studies (33% of all included studies) reported patients taking concomitant interacting medications at the CYP3A4 and/or P-glycoprotein efflux pump. Seventeen studies (81% of all included studies) reported ADEs leading to hospitalization. A multivariate analysis from one case-control study identified risk factors prognosticating myopathy ADEs in patients taking statin-colchicine therapy: comorbid renal disease and/or cirrhosis, colchicine doses 1.2 mg daily or greater, and concomitant interacting medications. Clinicians must be cognizant that the statin-colchicine drug interaction may lead to patient harm and thus should employ risk-mitigation strategies for statin-associated muscle symptoms. Future studies are warranted to validate clinically relevant risk factors that are strongly associated with the complications owing to the statin-colchicine drug interaction.

Evidence of Clinically Meaningful Drug-Drug Interaction With Concomitant Use of Colchicine and Clarithromycin

INTRODUCTION

Colchicine is currently approved for the treatment of gout and familial Mediterranean fever, among other conditions. Clarithromycin, a strong inhibitor of CYP3A4 and P-glycoprotein, dramatically increases colchicine's half-life, augmenting the risk of a life-threatening adverse reaction when used inadvertently with colchicine.

OBJECTIVES

The aim of this study was to examine the evidence and clinical implications of concomitant use of colchicine and clarithromycin.

METHODS

Case reports of colchicine-clarithromycin co-administration were searched using the FDA's Adverse Event Reporting System (FAERS) database. PubMed, EMBASE, and Web of Science electronic databases were also searched from January 2005 through November 2019 for articles reporting colchicine-clarithromycin concomitant use. Individual reports were reviewed to identify consequences of coadministration, dose, days to onset of interaction, symptoms, evidence of renal disease, time to resolution of symptoms, and Drug Interaction Probability Scale (DIPS) rating.

RESULTS

The FAERS search identified 58 reported cases, nearly 53% of which were from patients aged between 65 and 85 years. Of 30 reported deaths, 11 occurred in males, and 19 in females. Other frequent complications reported in FAERS included diarrhea (31%), pancytopenia (22%), bone marrow failure (14%), and vomiting (14%). From published literature, we identified 20 case reports of concomitant exposure, 19 of which were rated 'probable' and one 'possible' according to DIPS rating. Of these cases, four 'probable' patients expired. The documented onset of colchicine toxicity occurred within 5 days of starting clarithromycin, and death within 2 weeks of concomitant exposure.

CONCLUSION

Clinical manifestations of colchicine-clarithromycin interaction may resemble other systemic diseases and may be life threatening. Understanding this clinically meaningful interaction can help clinicians avoid unsafe medication combinations.

Colchicine-induced rhabdomyolysis: a review of 83 cases

A 74-year-old man with medical history significant for atrial fibrillation, hyperlipidaemia and coronary artery disease on atorvastatin presented to the emergency department with profound weakness. The patient reports he first noticed his weakness 4 weeks after starting colchicine, prescribed for recurrent pericarditis with pericardial effusion, a complication following recent coronary artery bypass grafting. The patient was also on prednisone therapy for presumed post-pericardiotomy syndrome. The weakness involved all four limbs but was more notable in the lower extremities, with preserved sensation and tenderness to palpation. Labs showed an elevated creatinine phosphokinase and serum creatinine consistent with rhabdomyolysis. Discontinuation of the offending medications, including colchicine and atorvastatin, as well as intravenous fluid resuscitation with physical rehabilitation, led to improvement in the patient's symptoms. He was eventually discharged to a rehabilitation facility to continue physical therapy.

A novel investigation of statins myotoxic mechanism: effect of atorvastatin on respiratory muscles in hypoxic environment

Myopathy is a well-known adverse effect of statins, affecting a large sector of statins users. The reported experimental data emphasized on mechanistic study of statin myopathy on large muscles. Clinically, both large muscles and respiratory muscles are reported to be involved in the myotoxic profile of statins. However, the experimental data investigating the myopathic mechanism on respiratory muscles are still lacking. The present work aimed to study the effect of atorvastatin treatment on respiratory muscles using rat isolated hemidiaphragm in normoxic & hypoxic conditions. The contractile activity of isolated hemidiaphragm in rats treated with atorvastatin for 21 days was investigated using nerve stimulated technique. Muscle twitches, train of four and tetanic stimulation was measured in normoxic, hypoxic and reoxygenation conditions. Atorvastatin significantly increased the tetanic fade, a measure of muscle fatigability, in hypoxic conditions. Upon reoxygenation, rat hemidiaphragm regains its normal contractile profile. Co-treatment with coenzyme Q10 showed significant improvement in defective diaphragmatic contractility in hypoxic conditions. This work showed that atorvastatin treatment rapidly deteriorates diaphragmatic activity in low oxygen environment. The mitochondrial respiratory dysfunction is probably the mechanism behind such finding. This was supported by the improvement of muscle contractile activity following CoQ10 co-treatment.

Toxic myopathies

PURPOSE OF REVIEW

Our aim is to highlight major advances reported in the last few years in drug-induced muscle toxicity.

RECENT FINDINGS

Our focus is on myopathies induced by statins and immune checkpoint inhibitors with a brief overview of rare steroid myopathies. Statin muscle injury is frequently because of direct toxicity rather than an autoimmune mechanism. Laboratory testing and muscle pathologic features distinguish these two conditions. Statin-associated necrotizing autoimmune myopathy (SANAM) is associated with an autoantibody in 66% of cases targeting the HMGCR enzyme. The later autoantibody is a marker for necrotizing autoimmune myopathy, regardless of statin exposure. In SANAM, MHC-I antigens are expressed on the surface of intact muscle fibers. Genetic HLA loci predispose patients exposed to statins to immunologic toxicity. SANAM requires long-term therapy with multiple immunosuppressive therapies. Immune checkpoint inhibitors are powerful emerging therapies for advanced cancer that pause a novel therapeutic challenge.

SUMMARY

This review is focused on statins, the most prevalent myotoxic drug class. In addition, we examine the accumulating body of evidence of muscle injury and its management with immune checkpoint inhibitors. We anticipate the reader to become more knowledgeable in recent discoveries related to these myotoxic drugs, and their mechanisms of action and management.

Propofol Is Mitochondrion-Toxic and May Unmask a Mitochondrial Disorder

There are indications that preexisting mitochondrial disorders or beta-oxidation defects predispose for propofol infusion syndrome. This review aimed at investigating if propofol infusion syndrome occurs exclusively in patients with mitochondrial disorder and if propofol can unmask a mitochondrial disorder. Propofol infusion syndrome has been reported in genetically confirmed mitochondrial disorder patients. In addition, muscle biopsy of patients with propofol infusion syndrome revealed complex IV or complex II deficiency. In animal studies propofol disrupted the electron flow along the respiratory chain and decreased complex I, complex II, and complex III of the respiratory chain. In addition, propofol disrupted the permeability transition pore and reduced the mitochondrial membrane potential. In conclusion, propofol is mitochondrion-toxic and mitochondrial disorder patients should not receive propofol in high dosages over a prolonged period of time. Short-term application of propofol should be safe even in mitochondrial disorder patients. Not only does propofol infusion syndrome occur in mitochondrial disorder patients, but mitochondrial disorder patients are likely at higher risk to develop propofol infusion syndrome. Patients who develop propofol infusion syndrome should be screened for mitochondrial disorder. Propofol infusion syndrome is preventable if risk factors are thoroughly assessed, and if long-term propofol is avoided in patients at risk for propofol infusion syndrome.

Colchicine-Induced Acute Neuromyopathy in a Patient Using Concomitant Fluconazole: Case Report and Literature Review

A 54-year-old woman presented at the emergency department after experiencing lower limb weakness and bilateral ankle pain for 2 days. She had a history of type 2 diabetes mellitus, diabetes mellitus nephropathy with chronic kidney disease, and chronic gouty arthritis. She had received 0.6 mg colchicine orally once or twice daily for 8 months. Four days prior to her emergency department visit, she was discharged from our nephrology ward, where she had been admitted because of a urinary tract infection. During hospitalization, she was treated with intravenous cefazolin for 7 days. Because of persistent symptoms, we performed repeated urinalysis, which revealed the presence of yeast. She was diagnosed with fungal cystitis, and was administered a 7-day course of once-daily oral fluconazole (100 mg). On day 5 of the course, she was discharged and asked to continue taking oral colchicine (0.6 mg, twice daily), as well as fluconazole for the full 7-day course. Neurological examination revealed marked symmetrical weakness (Medical Research Council grade 4/5). Her sensation and coordination were intact. Initial laboratory investigation revealed hyperkalemia (6.2 mmol/L), and blood urea nitrogen, serum creatinine, and creatine kinase levels of 181, 11.16 mg/dL, and 803 U/L respectively. Her liver function tests showed elevated alanine aminotransferase levels (112 U/L). Electromyographic results were consistent with colchicine neuromyopathy. Ten days after treatment cessation, muscle enzyme levels normalized and weakness gradually disappeared. We used the Drug Interaction Probability Scale to evaluate our patient’s case. A score of 5 was calculated, indicating that the drug–drug interaction was the probable cause of neuromuscular toxicity.

Progressive Organ Failure After Ingestion of Wild Garlic Juice

BACKGROUND

Wild garlic and related plants are increasingly sought after by fans of natural products. They can be confused with other plants containing colchicine and cause potentially fatal intoxications.

CASE REPORT

We report a case of accidental poisoning by Colchicum autumnale, which was mistaken for wild garlic (Allium ursinum). The patient initially presented with mild gastrointestinal symptoms, but progressed rapidly to agranulocytosis, paraparesis, and delirium before the causative agent was identified. The laboratory tests revealed rhabdomyolysis, coagulopathy, alteration of liver tests, and prerenal azotemia. Botanical examination confirmed the incriminated plant (Colchicum autumnale). Serum and urine analysis confirmed the presence of colchicine. The patient required intensive support therapy, and she fully recovered within 8 weeks. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Colchicine poisoning should be considered in the differential diagnosis of patients presenting with gastroenteritis after ingestion of wild garlic.

Toxic myopathies

Muscle tissue is highly sensitive to many substances. Early recognition of toxic myopathies is important, because they potentially are reversible on removal of the offending drug or toxin, with greater likelihood of complete resolution the sooner this is achieved. Clinical features range from mild muscle pain and cramps to severe weakness with rhabdomyolysis, renal failure, and even death. The pathogenic bases can be multifactorial. This article reviews some of the common toxic myopathies and their clinical presentation, histopathologic features, and possible underlying cellular mechanisms.

Effect of steady-state atorvastatin on the pharmacokinetics of a single dose of colchicine in healthy adults under fasted conditions

BACKGROUND AND OBJECTIVE

Colchicine is commonly prescribed for gout. While minimally metabolized by the cytochrome P450 (CYP) 3A4 isoenzyme, colchicine is a substrate for P-glycoprotein (P-gp). Atorvastatin is metabolized primarily by CYP3A4 and is a P-gp inhibitor. Patients with gout often have dyslipidemia; therefore, the potential for co-administration of atorvastatin and colchicine exists. The objective of this study was to determine the effect of oral atorvastatin on the pharmacokinetics of a single, oral dose of colchicine.

METHODS

Twenty-four healthy adult subjects were enrolled in this single-center, open-label, non-randomized, one-sequence, two-period drug-drug interaction study. On day 1, subjects received a single oral dose of colchicine 0.6 mg. After a 14-day washout, subjects received atorvastatin 40 mg once daily for 14 days followed by a single dose of colchicine 0.6 mg co-administered with atorvastatin 40 mg on day 28. Main outcome measures were colchicine maximum plasma concentration (C max), area under the plasma concentration-time curve (AUC) from time zero to the last measurable concentration (AUC last), and AUC from time zero to infinity (AUC∞), which were compared with and without concurrent atorvastatin.

RESULTS

Colchicine AUC last, AUC∞, and C max increased by 27, 24, and 31 %, respectively, when co-administered with atorvastatin. Corresponding 90 % confidence intervals around the ratios were outside the established no-effect 80-125 % interval.

CONCLUSION

Increased colchicine exposure was observed after a single dose of colchicine was administered with steady-state atorvastatin. Additional studies with multiple dosing of both drugs are needed to further determine the clinical implications of these results.

Rhabdomyolysis after midazolam administration in a cirrhotic patient treated with atorvastatin

The administration of statins in patients with liver disease is not an absolute contraindication. Hepatotoxicity is a rare and often dose-related event and in the literature there are only a few described cases of fatal rhabdomyolysis in patients with chronic liver disease after statin administration. During treatment with 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors, the factors responsible for myopathy may either be related to the patient, or due to interactions with other medications that are metabolic substrates of the same isozymes and therefore able to increase blood statin concentration. The most important side effects consist of increased transaminase levels, abdominal pain or muscle weakness, increased serum levels of creatine kinase and rhabdomyolysis. In this article we report a case of fatal rhabdomyolysis with acute renal failure after gastric endoscopy, where midazolam was used as a sedation agent in a patient with chronic liver disease treated with a high dose of atorvastatin. Therefore, we suggest paying particular attention to the potential risks of associating atorvastatin and midazolam in patients with chronic liver disease who need to undergo gastric endoscopy.

Statins and daptomycin: safety assessment of concurrent use and evaluation of drug interaction liability

BACKGROUND

Acute muscle injury and potentially fatal rhabdomyolysis may occur with use of statins and certain interacting medications. This investigation assessed risk for myopathy in patients receiving treatment with a statin in combination with daptomycin, a medication also associated with muscle injury.

METHODS

Patients hospitalized from July 1, 2005, through June 30, 2010, who received simvastatin or rosuvastatin concurrently with daptomycin were identified and their medical records were examined. Patients were judged to have treatment-related muscle injury if their records contained evidence of myalgia with or without weakness and secondarily impaired mobility together with elevated creatine kinase (CK) levels. These assessments were compared with similar data from hospitalized patients who received a statin alone.

RESULTS

A total of 52 patients received 66 courses of concurrent treatment with simvastatin or rosuvastatin and daptomycin. Of these, no patient (0%) met evidentiary requirements for diagnosis of myopathy or related complications. No patient (0%) developed muscle pain or discomfort and none developed markedly elevated CK levels. The incidence of asymptomatic elevations of CK in these simvastatin or rosuvastatin plus daptomycin recipients (9%) was statistically indistinguishable from the incidence of CK elevations found in a cohort of 105 inpatients who received simvastatin or rosuvastatin alone (21%; p=0.135).

CONCLUSIONS

In patients receiving treatment with simvastatin or rosuvastatin and daptomycin, no symptoms or objective evidence of muscle injury attributable to a drug interaction were identified. These findings are consistent with data indicating that the myopathic effects of statins and daptomycin are incited by disparate and perhaps unique pharmacological mechanisms. Risk of muscle injury therefore appears to be no greater when a statin is administered with daptomycin than when either medication is used alone.

Propofol infusion syndrome in a super morbidly obese patient (BMI = 75)

Propofol infusion syndrome (PRIS) is a rare but often fatal complication as a result of large doses of propofol infusion (4–5 mg/kg/hr) for a prolonged period (>48 h). It has been reported in both children and adults. Besides large doses of propofol infusion, the risk factors include young age, acute neurological injury, low carbohydrate and high fat intake, exogenous administration of corticosteroid and catecholamine, critical illness, and inborn errors of mitochondrial fatty acid oxidation. PRIS manifestation include presence of metabolic acidosis with a base deficit of more than 10 mmol/l at least on one occasion, rhabdomyolysis or myoglobinuria, acute renal failure, sudden onset of bradycardia resistant to treatment, myocardial failure, and lipemic plasma. The pathophysiology of PRIS may be either direct mitochondrial respiratory chain inhibition or impaired mitochondrial fatty acid metabolism mediated by propofol. We report a case of supermorbidly obese patient who received propofol infusion by total body weight instead of actual body weight and developed PRIS.

Informatics confronts drug-drug interactions

Drug-drug interactions (DDIs) are an emerging threat to public health. Recent estimates indicate that DDIs cause nearly 74000 emergency room visits and 195000 hospitalizations each year in the USA. Current approaches to DDI discovery, which include Phase IV clinical trials and post-marketing surveillance, are insufficient for detecting many DDIs and do not alert the public to potentially dangerous DDIs before a drug enters the market. Recent work has applied state-of-the-art computational and statistical methods to the problem of DDIs. Here we review recent developments that encompass a range of informatics approaches in this domain, from the construction of databases for efficient searching of known DDIs to the prediction of novel DDIs based on data from electronic medical records, adverse event reports, scientific abstracts, and other sources. We also explore why DDIs are so difficult to detect and what the future holds for informatics-based approaches to DDI discovery.

Assessment of the association between colchicine therapy and serious adverse events

STUDY OBJECTIVE

As data that prompted a 2009 labeling change detailing contraindications, precautions, and dosing recommendations for the first branded colchicine product were limited to case reports of myotoxicity and blood dyscrasias ascribed to the drug, we sought to quantify the association of colchicine therapy with serious adverse outcomes in a cohort of insured patients.

DESIGN

Case-control study.

DATA SOURCE

Kaiser Permanente Colorado electronic data warehouses and electronic medical records.

PATIENTS

Cases were patients with a creatine kinase (CK) level of at least 2000 U/L or who developed a clinically significant non-cancer-related blood dyscrasia (thrombocytopenia, neutropenia, leukopenia, aplastic anemia, or pancytopenia) between January 1, 2006, and June 30, 2009 (954 cases). Each case was matched to up to 10 controls by age, sex, and index date (date of the increased CK level or blood dyscrasia-supporting laboratory value). Controls were patients without elevated CK levels or blood dyscrasias who had a routine health maintenance examination during the same time period (index date was the date of their health maintenance examination [9007 controls]).

MEASUREMENTS AND MAIN RESULTS

The primary study outcome was colchicine exposure, defined as a colchicine prescription purchase in the 100 days before the index date. The likelihood of colchicine exposure was examined with conditional logistic regression. Cases experienced a higher rate of previous colchicine exposure compared with controls (0.6% vs 0.2%, odds ratio 3.9, 95% confidence interval 1.4-10.7). In addition, cases had higher hospitalization rates (14.9% vs 5.0%, p<0.001), higher mean chronic disease scores (2.5 vs 0.0, p<0.001), and were more likely to have been exposed to drugs that may increase the risk of adverse events due to an interaction with a CYP3A4 inhibitor drug (6.9% vs 2.3%, p<0.001).

CONCLUSION

Patients with confirmed elevations in CK level and/or blood dyscrasias had a higher rate of previous colchicine exposure, although low overall, and greater hospitalization rates and exposure to drugs that may increase the risk of adverse events compared with controls. These findings support the 2009 United States Food and Drug Administration labeling for the first branded colchicine product, cautioning use in patients with liver impairment or renal dysfunction and/or those receiving concurrent drugs that may increase risk of adverse events.

Identifying adverse drug reactions associated with drug-drug interactions: data mining of a spontaneous reporting database in Italy

BACKGROUND

Drug-drug interactions (DDIs) are an important cause of adverse drug reactions (ADRs). Many studies have recently considered this issue, but most of them focus only on potential interactions and are often related to the hospital setting. A spontaneous reporting database could be a valuable resource for detection of ADRs associated with DDIs; however, data in the literature are limited.

OBJECTIVE

To detect those patients treated with potentially interacting drugs and the cases where reported adverse reactions are a possible consequence of DDIs, using an Italian spontaneous reporting database.

METHODS

The data were obtained from a database containing all reports of suspected ADRs from five Italian regions (January 1990 to December 2007) that are the main contributors to the Italian spontaneous reporting system. All reports containing at least two drugs, reported as being suspected of causing the ADR or as concomitant medication, were selected and a list of drug pairs was drawn up. We performed a search to verify which drug pairs are considered a potential DDI, using the Internet version of the DRUGDEX(R) system. For each report containing a potential DDI, we verified whether the description of the adverse reaction corresponded to the interaction effect.

RESULTS

The database contained 45 315 reports, of which 17 700 (39.1%) had at least two reported drugs. We identified 5345 (30.2%) reports with potential DDIs, and in 1159 (21.7%) of these reports a related ADR was reported. The percentage of reports with potential DDIs increased in relation to the number of concomitantly administered drugs, ranging from 9.8% for two drugs to 88.3% for eight or more drugs. The percentages of serious or fatal reports of ADRs associated with a DDI were significantly higher than other reports analysed. The mean age, percentage of male patients and the mean number of drugs were also significantly higher in reports with DDIs than in other reports. In 235 of 1159 reports (20.3%), both interacting drugs were recognized as suspect by the reporter. This percentage varies in relation to the drugs involved, ranging from 2% to about 65%. The most frequently reported interaction was digoxin and diuretics, but no fatal ADRs were reported with this combination. The combination of anticoagulant and antiplatelet agents was responsible for the greatest number of serious reactions and deaths.

CONCLUSIONS

This study validates that spontaneous reporting, despite its limitations, can be an important resource for detecting ADRs associated with the concomitant use of interacting drugs. Moreover, our data confirm that DDIs could be a real problem in clinical practice, showing that more than one in five patients exposed to a potential DDI experienced a related ADR.

[Pharmacologically-induced neurocatastrophes]

Drug-induced adverse reactions represent a significant health problem in developed countries. These events cause 5% of hospital admissions and are one of the main causes of mortality. Neurological manifestations are among the most frequent. This article reviews catastrophic cerebrovascular situations and confusional syndromes, as well as epilepsy, structural encephalopathy, neuromuscular disorders, catastrophic movement disorders and infections, all of which can be drug-induced.

Colchicine in clinical medicine. A guide for internists

Colchicine (COL) has been used in medicine for a long time. It is well recognized as a valid therapy in acute flares of gouty arthritis, familial Mediterranean fever (FMF), Behçet's disease, and recurring pericarditis with effusion. It has also been used to treat many inflammatory disorders prone to fibrosis, mostly with disappointing therapeutic results. The pharmacotherapeutic mechanism of action of COL in diverse diseases is not fully understood, thought it is known that the drug accumulates preferentially in neutrophils, and this effect is useful in FMF. COL shows a large interindividual bioavailability. Furthermore, interactions with drugs interfering with CYP3A4 dependent enzymes and P-glycoprotein occur and are clinically important. The dosage of COL must be reduced in patients with relevant hepatic and/or renal dysfunction. However, when appropriately used and contraindications have been excluded, oral COL is a safe treatment.

Colchicine for the treatment of pericarditis

Colchicine has been effectively used in the treatment of several inflammatory conditions, such as gouty attacks, serositis related to familial Mediterranean fever, Behçet syndrome and more recently, in acute and recurrent pericarditis. Colchicine concentrates in white blood cells, particularly polymorphonuclear cells, inhibiting tubulin polymerization, thus interfering with migration and phagocytosis, and reducing the inflammatory cycle. Although the exact number of responders is unknown, the drug has been successfully used for the treatment and prevention of recurrences and to taper corticosteroids in patients with recurrent pericarditis in several retrospective studies and an open-label, randomized trial, where the recurrence rate was halved in the treatment arm. Less evidence supports the use of the drug for the treatment of acute pericarditis, where colchicine remains optional and requires further multicenter confirmatory studies. At present, colchicine has been recommended by the 2004 European guidelines on the management of pericardial diseases for acute (class IIa) and recurrent pericarditis (class I), but its use is still unlabeled and informed consent is required for prescription. A careful monitoring of possible contraindications, drug interactions and side effects is necessary. The aim of this paper is to review the evidence that supports the use of the drug in acute and recurrent pericarditis, as well as dosing and precautions for clinical use.

Molecular mechanisms of toxicity of simvastatin, widely used cholesterol-lowering drug. A review

Statins are widely used and well tolerated cholesterol-lowering drugs, and when used for therapy purposes reduce morbidity and mortality from coronary heart disease. Simvastatin is one of nine known statins, specific inhibitors of hepatic enzyme 3-hydroxy-3-methylglutaryl-coenzyme A reductase, the rate-limiting step of cholesterol biosynthesis, and is believed to reduce plasma cholesterol levels by decreasing the activity of this enzyme. Statin drugs represent the major improvement in the treatment of hypercholesterolemia that constitutes the main origin of atherosclerosis, leading to coronary heart disease. Although statins are generally safe, minor and severe adverse reactions are well known complications of statin use. Adverse events associated with simvastatin therapy are uncommon, but potentially serious. In this review some details about statins including their adverse effects in humans and animals, the effects of simvastatin on various intracellular and mitochondrial processes, and molecular mechanisms underlying simvastatin cytotoxicity are discussed.

Suspected statin-induced respiratory muscle myopathy during long-term inspiratory muscle training in a patient with diaphragmatic paralysis

BACKGROUND AND PURPOSE

Abnormal lipids are associated with the development of coronary heart disease; for this reason, lipid-lowering agents have become a standard of care. The purposes of this case report are: (1) to highlight the association of impaired inspiratory muscle performance (IMP) with statin therapy and (2) to describe potentially useful methods of examining and treating people with known or suspected statin-induced skeletal myopathies (SISMs).

CASE DESCRIPTION

The patient had breathlessness on exertion and a restrictive lung disorder from a right hemidiaphragmatic paralysis, for which he was prescribed high-intensity inspiratory muscle training (IMT). He had a secondary diagnosis of hyperlipidemia, which was treated with 40 mg of simvastatin after 5(1/2) months of IMT.

OUTCOMES

The improvements in IMP, symptoms, and functional status obtained from almost 6 months of high-intensity IMT were lost after the commencement of simvastatin. However, 3 weeks after termination of simvastatin combined with high-intensity IMT, the patient's IMP, symptoms, and functional status exceeded pre-statin levels.

DISCUSSION

This case report suggests that high-intensity IMT can be used effectively in a patient with impaired diaphragmatic function and during recovery from a respiratory SISM. The marked reduction in IMP and inability to perform IMT resolved with the cessation of statin therapy. The case report also highlights the potential effects of SISMs in all skeletal muscle groups. The clinical implications of this case report include the potential role of physical therapy in monitoring and possibly facilitating the spontaneous recovery of an SISM, as well as the need to investigate the IMP of a person with dyspnea and fatigue who is taking a statin.

Colchicine for pericarditis: hype or hope?

Colchicine has been effectively used in the treatment of several inflammatory conditions, such as gouty attacks, serositis related to familial Mediterranean fever, Behçet syndrome, and more recently also in acute and recurrent pericarditis. Growing evidence has shown that the drug may be useful to treat an acute attack and may be a way to cope with the prevention of pericarditis in acute and recurrent cases and after cardiac surgery. Nevertheless, clinicians are often sceptical about the efficacy of the drug, and concerns have risen on possible side effects and tolerability. In this review, we analyse current evidence to support the use of the drug, as well as possible harms and risks related to drug interactions, reaching the conclusion that colchicine is safe and useful in recurrent pericarditis, if specific precautions are followed, although less evidence supports its use for the treatment of acute pericarditis, where colchicine remains optional and there is a need for further multicentre confirmatory studies. This paper also reviews specific dosing and precautions for the clinical use.