Evaluation of the activity of CYP2C19 in Gujrati and Marwadi subjects living in Mumbai (Bombay)

BACKGROUND: Inherited differences in the metabolism and disposition of drugs, and genetic polymorphisms in the targets of drug therapy (e.g., receptors), can greatly influence efficacy and toxicity of medications. Marked interethnic differences in CYP2C19 (a member of the cytochrome P-450 enzyme superfamily catalyzing phase I drug metabolism) which affects the metabolism of a number of clinically important drugs have been documented. The present study evaluated the activity of CYP2C19 in normal, healthy Gujrati and Marwadi subjects by phenotyping (a western Indian population). METHODS: All subjects received 20 mg of omeprazole, which was followed by blood collection at 3 hrs to estimate the metabolic ratio of omeprazole to 5-hydroxyomeprazole. The analysis was done by HPLC. RESULTS: It was seen that 10.36% of this population were poor metabolizers(PM) whereas 89.63% were extensive metabolizers(EM). CONCLUSION: A genotyping evaluation would better help in identifying population specific genotypes and thus help individualize drug therapy

Systematic review of drug utilization studies & the use of the drug classification system in the WHO-SEARO Region

Background & objectives: Information available on drug consumption is inadequate in most low and middle income countries. This systematic review was conducted to analyse published work on drug utilization research/studies (DUR) in the SEARO region of WHO for study objectives, methodology, results and recommendations and to identify the need for improving DUR and the use of the ATC/DDD system. Methods: A literature search for DUR was carried out in biomedical databases (PubMed, Scirus, Scopus and Google Scholar) up to May 2012. Publications were selected if those were in the English language, describing DUR or prescription practices, and study conducted in the WHO-SEARO countries. Results: A total of 318 publications were included in the review. Of these, 67 per cent were from India and 13 per cent were from Thailand. Majority of the publications were hospital based; only 16 per cent were community based. The ATC/DDD system was used in only 20 per cent of the publications, of which 73 per cent publications used DDD indicators. Several publications focused on antibiotics (31%). Publications that recommended the need for a policy or intervention to improve prescription practices/rational drug use amounted to 35 per cent. Interpretation & conclusions: Drug utilization studies using ATC/DDD system need to be promoted and carried out on an ongoing basis. DUR is important for rational use of drugs. Its relevance to policy making and resource allocation needs to be emphasized

A retrospective analysis of adverse events in the elderly in a tertiary referral center in Mumbai (Bombay), India

Background : Adverse events (AEs) account for significant morbidity and mortality in elderly. Inappropriate medication usage has been regarded as an important factor contributing to AEs in them. Beers criteria are a set of standard criteria for guiding drug prescription in elderly. Objective : To estimate the burden of AEs in the elderly in India and use of Beers criteria for assessing appropriateness of drug prescription in them. Materials and Methods : Data on AEs collected by our tertiary referral center for the years 2005 and 2006 was analyzed. The term ′elderly individuals′ was defined as those aged ≥58 years. An AE was defined as any untoward medical occurrence with a medicinal product in a patient or a clinical investigation, whether or not causally related. Results : In 2005, 321 AEs were reported, and in 2006 there were 673. Of them, those in the elderly constituted 60 (18.9%) and 44 (11.8%) AEs in the 2 years, respectively. About 7 (11.6%) of the AEs in elderly in 2005 were due to medications not fulfilling Beers criteria but none in 2006. Two thirds of the AEs in both years were found to be due to antidiabetics, oral anticoagulants and antiplatelets and drugs with a narrow therapeutic index. Warfarin, digoxin and insulin accounted for a quarter of the AEs. Conclusions : Some commonly used medications account for a major proportion of AEs in elderly. Prospective studies of similar nature could further help us assess the burden of AEs in elderly

Anticonvulsant hypersensitivity syndrome to lamotrigine confirmed by lymphocyte stimulation in vitro

Anticonvulsant hypersensitivity syndrome (AHS) developing to lamotrigine, a non-aromatic anticonvulsant, has rarely been reported. We present a two-year-old boy with refractory epilepsy on valproic acid and lamotrigine therapy who developed fever and a maculopapular itchy rash. Blood investigations detected lymphocytosis and thrombocytopenia. With a presumptive diagnosis of AHS, lamotrigine was discontinued. The fever and rash resolved over the next three days and the child was discharged on valproic acid and clobazam. The diagnosis was confirmed by in vitro lymphocyte toxicity assay, which not only demonstrated increased cell death following exposure to lamotrigine, but also to the three first-line aromatic anticonvulsants: phenytoin, phenobarbital and carbamazepine. The potential of first-line aromatic anticonvulsants to cause AHS should be remembered in a patient who has developed AHS on exposure to lamotrigine. Timely recognition of this rare but potentially fatal drug reaction is important

Evaluation of evidence for pharmacokinetics-pharmacodynamics-based dose optimization of antimicrobials for treating Gram-negative infections in neonates

Background & objectives: Neonates present a special subgroup of population in whom optimization of antimicrobial dosing can be particularly challenging. Gram-negative infections are common in neonates, and inpatient treatment along with critical care is needed for the management of these infections. Dosing recommendations are often extrapolated from evidence generated in older patient populations. This systematic review was done to identify the knowledge gaps in the pharmacokinetics-pharmacodynamics (PK-PD)-based optimized dosing schedule for parenteral antimicrobials for Gram-negative neonatal infections. Methods: Relevant research questions were identified. An extensive electronic and manual search methodology was used. Potentially eligible articles were screened for eligibility. The relevant data were extracted independently in a pre-specified data extraction form. Pooling of data was planned. Results: Of the 340 records screened, 24 studies were included for data extraction and incorporation in the review [carbapenems - imipenem and meropenem (n=7); aminoglycosides - amikacin and gentamicin (n=9); piperacillin-tazobactam (n=2); quinolones (n=2); third- and fourth-generation cephalosporins (n=4) and colistin nil]. For each of the drug categories, the information for all the questions that the review sought to answer was incomplete. There was a wide variability in the covariates assessed, and pooling of results could not be undertaken. Interpretation & conclusions: There is a wide knowledge gap for determining the doses of antimicrobials used for Gram-negative infections in neonates. A different profile of newborns in the developing countries could affect the disposition of antimicrobials for Gram negative infections, necessitating the generation of PK-PD data of antimicrobials in neonates from developing countries. Further, guidelines for treatment of neonatal conditions may incorporate the evidence-based PK-PD-guided dosing regimens