Current Drug Safety - Volume 7, Issue 1, 2012

Antidepressants are amongst the most commonly prescribed classes of drugs and their use continues to grow. The World Health Organisation estimates that depression effects approximately 121 million people worldwide, with 26 million people receiving some form of medical care for depression [1]. A large number of these people will be treated with antidepressants. Moreover, antidepressants are commonly administered to special populations, such as the elderly, children and women during reproductive life stages. Depression is also commonly associated with comorbid physical illnesses [2], being overweight [3], tobacco smoking [4], poor diet [5] and lack of physical activity [6]. Large numbers of people being treated, often with vulnerabilities, increases the likelihood of adverse drug reactions to antidepressant treatment. Adverse effects associated with antidepressant treatments have been well documented and vary with agent, dose and interindividual factors. Effects range from common to very rare, mild to life threatening. Adverse events are part of the landscape in prescribing medications. Treatment outcomes are optimised when management of safety issues are an integral part of practice. I recently had the privilege of being part of an expert working group that recently published safety monitoring guidelines for antidepressant treatments [7]. These guidelines present an overview of screening and safety considerations for antidepressant treatment and make recommendations for safety monitoring. Recommendations are made to assist with the decision to treat, including the diagnostic work up and assessing the risk versus benefit of treatment, screening and assessments prior to the initiation of treatment and recommendations for ongoing monitoring during treatment. Surprisingly, these guidelines are the first of their type, although there are previous safety monitoring guidelines for schizophrenia [8], bipolar disorder [9] and specific agents such as clozapine [10]....

Purpose: We recently reported an increased incidence of serious bleeding events and mortality in patients with baseline bleeding precautions treated with drotrecogin alfa (activated) compared to patients without such precautions. Whether these observations were specific to our single medical campus is unclear. Methods: All patients who received drotrecogin alfa (activated) for the treatment of severe sepsis from January 2006 through September 2009 within the South Central Veterans Affairs Health Care Network were retrospectively reviewed using a regional clinical database. Demographic information, bleeding precautions that were exclusion criteria of the PROWESS trial, and 30-day post-discharge incidences of serious bleeding events and mortality were collected. Results: Seventy-nine patients from 5 medical centers were included. Serious bleeding events occurred in 4 of 24 patients (16.7%) with any bleeding precaution vs 1 of 55 patients (1.8%) without a bleeding precaution (P=0.03). All patients (5) who experienced a serious bleeding event died compared to 39 of 74 patients (52.7%) who did not (P=0.06). Seventeen of 24 patients (70.8%) with bleeding precautions died vs 27 of 55 patients (49.1%) without bleeding precautions (P=0.07). The number of serious bleeding events did not allow meaningful multivariate analyses. The mean number of failing organs was an independent predictor of 30-day post-discharge mortality (OR 1.63 for each organ failed, 95% CI 1.05– 2.6). Conclusions: The findings of this study were consistent with our prior observations and suggest the risk for serious bleeding events with drotrecogin alfa (activated) may outweigh any potential benefit in patients with baseline bleeding precautions.

Background: Mineralocorticoids are thought to play a role in tissue repair, including fibrous tissue formation. The antimineralocorticoid activity of spironolactone has been linked to an increased risk of gastrointestinal bleeding. Drospirenone is a synthetic progestin approved in combination with ethinyl-estradiol as an oral contraceptive (OC). It is a spironolactone-derivative, and its antimineralocorticoid effects could irritate the gastrointestinal tract leading to symptoms of irritable bowel syndrome (IBS). Methods: A retrospective cohort study was conducted evaluating women 18-46 years of age in the IMS claims-database. New-users of progestin-based OCs were identified between 1997-2009. Ninety days of OC therapy and one year of prior enrollment with no prior diagnosis of IBS were required for inclusion. Cases were identified using a previously validated method for the diagnosis of IBS. Cox proportional hazards models were used to estimate the hazard ratio (HR) for developing IBS with the different OC formulations using levonorgestrel as a reference. Results: The cohort included 939,281 women, averaging 29.1 years of age and 247 days of OC therapy. 3,050 incident cases of IBS were detected. The annualized incidence for IBS with drospirenone was 0.77% (1083 cases) while that for levonorgestrel was 0.46% (483 cases). The crude HR for development of IBS with drospirenone compared to levonorgestrel was 1.70 (95%CI 1.53-1.90), while the adjusted HR was 1.63 (95%CI 1.46-1.82). Multiple sensitivity analyses confirmed this association. Other OCs were unassociated with IBS. Conclusion: Our study found a positive association between drospirenone and a diagnosis of IBS that was not observed with other OCs.

Background: To investigate whether features of muscular complaints (MC) differ between receivers of a statin prescription and non-receivers. To analyze the relationship between analgesics prescription, statin prescription and/or musculoskeletal disorders. Methods: Cross-sectional study. Consecutive patients in offices of family practitioners were interviewed using a standardized questionnaire. Target variables: Rates of features of MC in patients with or without a statin prescription and rates of analgesic drug prescription in patients with or without statin prescription and/or musculoskeletal disorders. Odds ratios (adjusted for age, sex, and socio-economic status) were calculated using logistic regression analysis. Results: 1135 patients in 26 general practitioners’ offices were asked to participate, and 1031 patients agreed. Features of MC did not differ between the two groups of patients. Analgesic prescription was found to be associated with statin prescription in patients without musculoskeletal disorders (OR 2.2, CI 1.1-4.7 without statin, OR 2.5, CI 0.9-6.9 with statin) and particularly in those with musculoskeletal disorders (OR 5.2, CI 2.9-9.3 without statin, OR 9.3, CI 4.5-19.1 with statin). Conclusions: Analgesic prescriptions are probably positively associated with statin prescription. Assuming that analgesics attenuate MC, an even stronger association between MC and statin use seems likely. The results generate the hypothesis that statin use contributes to analgesic use in primary care patients.

Second-generation antipsychotics have been growingly implicated in the acute and maintenance treatment for bipolar affective disorder (BAD). Risperidone long-acting injection (LAI) has been the first second-generation depot indicated for its maintenance treatment. However, its long-term motor side-effects, especially tardive dyskinesia (TD), has not been commonly reported or studied. The case reported here a bipolar patient with atypical presentation of TD involving only the crico-hyoid region of the neck associated with the use of risperidone LAI in adjunct to lithium and sodium valproate as maintenance therapy.

Objective: To describe a patient in whom initiation of micronized fenofibrate precipitated mycophenolate induced neutropenia. Case Summary: A 57-year-old man was admitted to the hospital because of febrile neutropenia. He had undergone kidney transplantation seventeen years ago. The patient's immunosuppressive maintenance regimen consisted of mycophenolate mofetil (MMF) 500 mg three times a day, and meprednisone 4 mg daily. His medical history included, hypertension treated with losartan 50mg daily, and dyslipidemia treated with ezetimibe 10mg /simvastatin 20mg for four years (until 2 weeks before admission when micronized fenofibrate 200 mg per day was started because of persistently elevated triglycerides levels. On presentation temperature was 37.8ºC and initial laboratory tests showed 3130 White Blood Cell Count(WBC)/μL with neutropenia (absolute neutrophil count (ANC) 313/μL) Fenofibrate and mycophenolate mofetil were discontinued, piperacillin tazobactam 4.5gr three times a day and granulocyte stimulation factor 300 μg/day were started. Three days after admission WBC was 7280/μL, neutrophils: 22%, ANC: 1160/mm3. Mycophenolate mofetil was restarted and granulocyte stimulation factor was discontinued. One month after discharge his WBC was 4480/μL and ANC 1926/μL. Discussion: The initiation of fenofibrate in a patient on stable and therapeutic doses of mycophenolate may have precipitated mycophenolate induced neutropenia, a well described, dose dependent phenomenon. Mycophenolic acid (MPA) displays a complex pharmacokinetic profile susceptible to potential significant interactions with fenofibrate. Since approximately 99% of MPA and fenofibrate bind to albumin, displacement may occur, leading to increased free MPA. Second competition of fenofibric acid for UGT1A9 an enzyme implicated in conjugation of MPA may have decreased its metabolism. The combination of these two effects may increase the risk of dose dependent neutropenia. Using the Interaction Probability Scale (DIPS), the interaction was designated as probable. Conclusions: Until further evidence is available, when fenofibrate is started in a renal transplant patient on mycophenolate careful monitoring should be considered to avoid potentially fatal complications.

Background: Rivastigmine is an acetylcholine esterase inhibitor used in the treatment of dementia. Patches with rivastigmine for transdermal delivery have been used to increase compliance and to reduce side effects. Case Report: We describe an 87-year old male with dementia treated with multiple rivastigmine patches (Exelon 9,5 mg/24 h) who developed nausea, vomiting and renal failure with disturbed electrolytes resulting in death. The symptoms occurred after six rivastigmine patches had concomitantly been erroneously applied by health care personnel on two consecutive days. The terminal cause of death was considered to be uremia from an acute tubular necrosis that was assessed as a result of dehydration through vomiting. The rivastigmine intoxication was assessed as having caused or contributed to the dehydrated condition. The medication error occurred at least partly due to ambiguous labeling. The clinical signs were not initially recognized as adverse effects of rivastigmine. Discussion: The presented case is a description of a rivastigmine overdose due to a medication error involving patches. This case indicates the importance of clear and unambiguous instructions to avoid administration errors with patches and to be vigilant to adverse drug reactions for early detection and correction of drug administration errors. In particular, instructions clearly indicating that only one patch should be applied at a time are important.

Statins are useful in the treatment of dyslipidemia commonly associated with hypertension and diabetes mellitus. They are not devoid of side effects chief of which are musculo-skeletal.Memory impairment as a side effect is not common; and has not been reported in Nigeria to author’s knowledge. This case report is on a woman who with Simvastatin developed memory deficits which adversely affected activities of daily living. Clinicians are enjoined to be on the alert for this, and should respond appropriately when it arises.

A 55 years old male patient, who is planned for bronchoscopy developed central anti-cholinergic syndrome due to therapeutic dose of atropine. Withdrawal of atropine has improved the symptoms. Thereafter, instillation of atropine as eye drops leads to reappearance of symptoms. The reaction was definite according to Naranjo’s algorithm. It was severe and definitely preventable according to Modified Hartwig and Siegel’s scale and Modified Schumock and Thornton scale respectively. Central anti-cholinergic syndrome may be due to variation in the genetic susceptibility (Idiosyncrasy) to atropine. Idiosyncratic reaction on administration of atropine as a pre-anesthetic medication or eye drops should be kept in mind while prescribing.

Three-dimensional (3D) in vitro systems that can mimic organ and tissue structure and function in vivo, will be of great benefit for a variety of biological applications from basic biology to toxicity testing and drug discovery. There have been several attempts to generate 3D tissue models but most of these models require costly equipment, and the most serious disadvantage in them is that they are too far from the mature human organs in vivo. Because of these problems, research and development in drug discovery, toxicity testing and biotech industries are highly expensive, and involve sacrifice of countless animals and it takes several years to bring a single drug/product to the market or to find the toxicity or otherwise of chemical entities. Our group has been actively working on several alternative models by merging biomaterials science, nanotechnology and biological principles to generate 3D in vitro living organs, to be called “Human Organs-on-Chip”, to mimic natural organ/tissues, in order to reduce animal testing and clinical trials. We have fabricated a novel type of mechanically and biologically bio-mimicking collagen-based hydrogel that would provide for interconnected mini-wells in which 3D cell/organ culture of human samples in a manner similar to human organs with extracellular matrix (ECM) molecules would be possible. These products mimic the physical, chemical, and biological properties of natural organs and tissues at different scales. This paper will review the outcome of our several experiments so far in this direction and the future perspectives.

Aims: The antifibrinolytic drug tranexamic acid (TXA) improves survival after trauma. Antifibrinolytic drugs may also improve outcome after spontaneous bleeding, so we conducted a systematic review of the frequency of thrombotic events associated with their use after spontaneous bleeding, to help design future randomized controlled trials. Methods: We sought trials or observational studies of ≥20 adults involving any antifibrinolytic drug (TXA, epsilonaminocaproic acid (EACA) or aprotinin) for spontaneous (non-traumatic, non-surgical/iatrogenic), non-heamophiliac bleeding. We searched the Cochrane Central Register of Controlled Trials, OVID Medline from 1966, EMBASE from 1980, and the bibliographies of relevant articles in October 2009. We meta-analysed proportions of patients with thrombotic events, using a random effects model. Results: We found 57 studies involving 5,049 patients, 3,616 (72%) of whom had spontaneous subarachnoid haemorrhage. 3,414 (68%) patients received TXA-based treatment and 1,635 (32%) received EACA. The frequencies of limb ischaemia and myocardial infarction were <1% for TXA and EACA. The frequency of deep vein thrombosis or pulmonary embolism was 1.9% (95% confidence interval (CI) 1.1 to 2.9) for TXA and 3.0% (95% CI 1.8 to 4.6) for EACA. The occurrence of cerebral infarction was restricted to studies of subarachnoid haemorrhage when compared to other indications, both for TXA (9.7% [95% CI 5.5 to 14.8] versus 0% [95% CI 0 to 0.5]) and for EACA (7.7% [95% CI 1.8 to 17.4] versus 0% [95% CI 0 to 2.1]). Conclusions: Thrombotic events have occurred infrequently with antifibrinolytic drugs after spontaneous bleeding apart from subarachnoid haemorrhage, so further exploration of their safety and efficacy after spontaneous bleeding is justified in randomized trials.

Clozapine, an atypical antipsychotic, is a dibenzodiazepine derivative and its therapeutic effects are probably mediated by dopaminergic and serotonergic activity. In accordance to several studies, it appears to be the most effective antipsychotic drug for treatment-resistant schizophrenia. Moreover, clozapine appears to be particularly beneficial in patients with schizophrenia who are suicidal and in those with comorbid substance use disorder. However, despite its efficacy, the general use of clozapine in clinical practice is somewhat limited because of the risk of several serious adverse effects such as agranulocytosis and thromboembolism. Clozapine may be associated with fatal myocarditis and cardiomyopathy in physically healthy young adults. Consequently, the FDA and the drug's manufacturer have strengthened warnings to include that a potentially fatal myocarditis may occur when taking clozapine. In the present paper the literature on clozapine-related myocardis will be reviewed and practical advice will be given concerning the diagnosis and management of such potentially fatal adverse effect.

Impulsive and compulsive behaviors, including pathologic gambling, hypersexuality, compulsive shopping, compulsive eating, excessive engagement in hobbies, punding, and Dopamine Dysregulation Syndrome (DDS), are increasingly reported serious side-effects of dopaminergic medication, used in the treatment of Parkinson's Disease (PD) and other disorders. Dopamine Agonists (DA) are strongly related with Impulse Control Disorders (ICDs), while L-dopa is associated with DDS. The present paper focuses on ICDs. The estimated prevalence of ICDs in PD patients treated with DA is as high as 14%. ICDs pathophysiology is complex, due to multiple contributing factors. Dopamine neurotransmission along the meso-cortico-limbic pathway is a modulator of risk behavior and can be altered in PD and in the course of dopaminergic treatment. Psychiatric complications, associated with treatment of PD are still underdiagnosed, although their consequences can be serious, even catastrophic. Physicians treating PD with DA should warn the patients and their relatives of the risk of inducing ICDs. Psychiatrists should be trained to recognize these side effects, that can mimic primary psychiatric conditions. The management of ICDs includes discontinuation of DA or switching from DA to other drugs for the treatment of PD. Cognitive behavior therapy, serotonin selective reuptake inhibitors, nalmefene, zonisamide, low dose of anti-dopaminergic drugs, as quetiapine or clozapine, can be effective. Psychological, spiritual, and ethical support (familial or individual) can help.

Aliskiren is the first known representative of a new class of non-peptide orally active renin inhibitors that blocks the renin-angiotensin-aldosterone-system (RAAS) at its rate-limiting step. It induces a net reduction in plasma renin activity (PRA), angiotensin II and aldosterone levels. Aliskiren is effective in reducing blood pressure (BP) and is well tolerated. The incidence of adverse events and the number of study discontinuations as a result of adverse events during aliskiren treatment were relatively low and generally not dissimilar from placebo. In placebo-controlled studies, aliskiren showed a dose-related systolic/diastolic BP lowering effect at doses between 75 and 300 mg/day. When compared to active treatments, aliskiren was generally as effective as hydrochlorothiazide, angiotensin-converting-enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs) and beta-blockers, in reducing BP. Aliskiren exhibits synergistic effects when combined with drugs that lead to a reactive increase in the PRA, such as diuretics, ACE inhibitors or ARBs. Although in clinical studies aliskiren proved to reduce proteinuria, the early termination of the Aliskiren Trial in Type 2 Diabetes Using Cardiovascular and Renal Disease Endpoints (ALTITUDE) confirms previous concerns about the full suppression of the RAAS, in this case with aliskiren combined with ACEinhibitors or ARBs, in patients with diabetes and concomitant renal impairment. This review summarizes the available data on its safety profile and its clinical development for treatment of arterial hypertension, diabetes and nephropathy.