Title: Drug – Drug Interaction of Phenytoin and Isoniazid

Authors: Dr Sonali Ramakant More, Dr Balasaheb Baburao Ghongane, Dr Bharti Ramchand Daswani

 DOI:  https://dx.doi.org/10.18535/jmscr/v5i4.34

Abstract

Phenytoin is a first line anti-epileptic drug; however side effects and drug interactions are seen with it frequently as it is a narrow therapeutic indexed antiepileptic drug. Many drugs competitively inhibit iso-enzymes responsible for its metabolism when concurrently administered and increases the phenytoin plasma concentration leading to serious adverse effects. One such case is being reported with phenytoin toxicity due to concurrent administration of phenytoin and isoniazid. It reflects the possibility of potential drug-drug interactions, as well as aims to highlight the importance of spontaneous reporting of adverse drug reactions amongst prescribing physicians and therapeutic drug monitoring in case of drugs with low safety margin. 

Keywords-Drug Interaction, Phenytoin toxicity, Isoniazid, therapeutic drug monitoring.

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Corresponding Author

Dr Sonali Ramakant More*

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