Detect Drug Interactions with Metronidazole

Abstract

Introduction: Metronidazole has been prescribed to treat infections for over a century and continues to be helpful in the therapy of amoebiasis, trichomoniasis, and giardiasis. Metronidazole is a cost-effective medication because of its low price, few adverse effects, and favorable pharmacokinetic and pharmacodynamic properties; nevertheless, it interacts with a wide variety of other medications. Some interactions with other medicines diminish its effectiveness, while others increase it.
 Aims: The study aims to detect and evaluate metronidazole interactions with other medicines at King Abdulaziz Specialist Hospital.
 Methodology: This retrospective study encompasses the review of 360 computerized prescriptions inside the outpatient clinic at King Abdulaziz Specialist Hospital in Saudi Arabia between March and September 2020 to detect and evaluate interactions among metronidazole and different medications.
 Results: Metronidazole interactions are mostly major or moderate. Metronidazole had the most common interactions with domperidone (15.83 %), famotidine (13.89 %), and ciprofloxacin (11.67 %). Metronidazole contains a nitroimidazole ring, which suppresses the metabolism in the liver of numerous medications, including those that may be metabolized by the CYP3A4 and/or CYP450 2C9 isoenzymes. The combination of metronidazole with phenytoin or phenobarbital can cause metronidazole elimination to be accelerated and phenytoin clearance to be reduced. Metronidazole may improve warfarin's anticoagulant effects, leading to a longer prothrombin time and a higher risk of bleeding. Concurrent use of metronidazole with alfuzosin, escitalopram, and ondansetron may raise the risks of QT-interval prolongation and arrhythmias.
 Conclusion: Most metronidazole drug interactions can be avoided by following excellent clinical care and clinical pharmacology concepts, such as avoiding complex treatment regimens, educating patients. and identifying patient risk factors. Furthermore, before prescribing and dispensing medicines, physicians and pharmacists should utilize drug-drug interactions checkers such as Micromedex and Lexicomp or a book such as Stockley's Drug Interactions.

Clinically important pharmacokinetic drug-drug interactions with antibacterial agents

“…Metronidazole is an antibiotic derived from nitroimidazoles indicated mainly for anaerobic microorganisms and protozoa. Metronidazole can interact with other drugs due to the ring in its structure that inhibits (weakly) the hepatic metabolism of several pharmacological compounds metabolized by the CYP450 2C9 and/or CYP3A4 isoenzyme [ 122 , 123 ]. Inhibition of these isoenzymes increases the concentration of drugs such as warfarin and other coumarin anticoagulants.…”