Neuroleptic malignant syndrome or a statin drug reaction? A case report

HyperCKemia and rhabdomyolysis in the neuroleptic malignant and serotonin syndromes: A literature review

Neuroleptic malignant syndrome and serotonin syndrome are two syndromes whose molecular bases remain poorly understood. The phenotypes of both syndromes overlap with other syndromes that have a clear genetic background, in particular RYR1-related malignant hyperthermia. Through a literature review, performed according to the PRISMA guidelines, we aimed to report the clinical features of both syndromes, and the results of genetic testing performed. 10 case series and 99 case reports were included, comprising 134 patients. A male predominance of 58% was found. The median age was 35 (range 4-84) years. Eight patients experienced recurrent episodes of rhabdomyolysis. Genetic analysis was performed in eleven patients (8%), revealing four RYR1 variants, three likely benign (p.Asp849Asn, p.Arg4645Gln, p.Arg4645Gln) and one variant of uncertain significance (p.Ala612Thr). This review underlines that a subset of patients with neuroleptic malignant syndrome and serotonin syndrome develop recurrent episodes of rhabdomyolysis. This recurrent pattern suggests a possible underlying (genetic) susceptibility. However, the genetic background of neuroleptic malignant syndrome and serotonin syndrome has only been investigated to a very limited degree so far. The increasing availability of next generation sequencing offers an opportunity to identify potentially associated genetic backgrounds, especially in patients with recurrent episodes or a positive family history.

Interaction potential between clarithromycin and individual statins-A systematic review

The high prevalence of statin and clarithromycin utilization creates potential for overlapping use. The objectives of this MiniReview were to investigate the evidence base for drug-drug interactions between clarithromycin and currently marketed statins and to present management strategies for these drug combinations. We conducted a systematic literature review following PRISMA guidelines with English language studies retrieved from PubMed and EMBASE (from inception through March 2019). We included 29 articles (16 case reports, 5 observational, 5 clinical pharmacokinetic and 3 in vitro studies). Based on mechanistic/clinical studies involving clarithromycin or the related macrolide erythromycin (both strong inhibitors of CYP3A4 and of hepatic statin uptake transporters OATP1B1 and OATP1B3), clarithromycin is expected to substantially increase systemic exposure to simvastatin and lovastatin (>5-fold increase in area under the plasma concentration-time curve (AUC)), moderately increase AUCs of atorvastatin and pitavastatin (2- to 4-fold AUC increase) and slightly increase pravastatin exposure (≈2-fold AUC increase) while having little effect on fluvastatin or rosuvastatin. The 16 cases of statin-clarithromycin adverse drug reactions (rhabdomyolysis (n = 14) or less severe clinical myopathy) involved a CYP3A4-metabolized statin (simvastatin, lovastatin or atorvastatin). In line, a cohort study found concurrent use of clarithromycin and CYP3A4-metabolized statins to be associated with a doubled risk of hospitalization with rhabdomyolysis or other statin-related adverse events as compared with azithromycin-statin co-administration. If clarithromycin is necessary, we recommend (a) avoiding co-administration with simvastatin, lovastatin or atorvastatin; (b) withholding or dose-reducing pitavastatin; (c) continuing pravastatin therapy with caution, limiting pravastatin dose to 40 mg daily; and (d) continuing fluvastatin or rosuvastatin with caution.

Statins and Inflammation: New Therapeutic Opportunities in Psychiatry

Statins, which are widely used to treat hypercholesterolemia, have anti-inflammatory and anti-oxidant effects. These are thought to be responsible for the potential effects of statins on various psychiatric disorders. In this study, we comprehensively review the literature to investigate the effects of statins on various psychiatric disorders including depression, schizophrenia, and dementia. In addition, we review adverse effects and drug interactions of statins to give clinically useful information guiding statin use in the psychiatric field. Statins seem useful in reducing depression, particularly in patients with physical disorders such as cardiovascular disease. In patients with schizophrenia, negative symptoms may be reduced by adjuvant statin therapy. Studies on cohorts at risk for dementia have generally shown protective effects of statins, while those on treatment for dementia show inconsistent results. In conclusion, statins used in combination with conventional psychotropic medications may be effective for various psychiatric disorders including depression, schizophrenia, and dementia. Further study is required to determine optimal doses and duration of statin use for the treatment of psychiatric disorders.

Quetiapine and clarithromycin-induced neuroleptic malignant syndrome

We report a case of neuroleptic malignant syndrome possibly caused by the combined administration of quetiapine and clarithromycin in a 75-year-old male patient. He was receiving quetiapine regularly. Two days before his admission to the hospital, he had been feverish and started receiving clarithromycin without consulting a doctor. Clarithromycin administration was interrupted 3 days after his admission because it was ineffective and because his clinical state was deteriorating. The patient presented altered level of consciousness and excessive muscular rigidity on his limbs, while he remained feverish (38.7 °C). Laboratory abnormalities included elevated serum creatine phosphokinase level (5.387 U/L), leukocytosis, and low serum iron. The patient was diagnosed with neuroleptic malignant syndrome, and quetiapine was immediately discontinued. After the following days, his muscle rigidity and mental status ameliorated, his fever withdrew, and his laboratory findings improved. The various features of the case are discussed in view of the fact that the concomitant administration of cytochrome 3A4 inhibitors, such as clarithromycin, is suggested to cause an increase of plasma concentrations of quetiapine. Thus, physicians should have a high index of suspicion of the interactions of commonly administered medications.