Coumadin and NSAIDs(Advil, Aleve, Nabumetone, etc.) probably one of the worst drug-drug interactions, in fact the AMDA lists it as one of its top ten in long-term-care/geriatrics. http://www.amda.com/tools/clinical/m3/topten.cfm – NSAIDs can cause issues with...
Coumadin (warfarin, Jantoven) has a lot of drug interactions! This is one of the key traits of Coumadin that makes it difficult to manage at times. One case I remember was an individual with dual infections going on and they were on Diflucan (fluconazole) for a...