Ketoprofen drug interactions

A study found that diclofenac 100 mg daily did not affect the pharmacokinetics of methotrexate however, 5 patients taking low-dose methotrexate 7.5 to 12.5 mg weekly for psoriasis or rheumatoid arthritis developed serious/fatal neutropenias. These cases probably involved other drug interactions, but diclofenac may have been an additional factor in two of them. Other cases involving diclofenac are mentioned in the sections on indometacin (k) and ketoprofen (1). 

To explore the frequency of continuous use of over-the-counter drugs and the potential for harmful interactions between OTC drugs and prescribed drugs, a population-based interview survey was conducted in 10 477 subjects (231). Daily use of over-the-counter drugs was reported by 7% of the subjects and 4% of those who used over-the-counter drugs had taken combinations with potential for clinically significant interactions. Interactions were most common for NSAIDs such as ketoprofen (15% of keto-profen users), ibuprofen (10%), and aspirin (6%). Unfortunately, this study did not provide information on whether the potential interactions led to actual clinical problems. 

Abebe W 2002 Herbal medication potential for adverse interactions with analgesic drugs. Journal of Clinical Pharmacy and Therapeutics 27 391-401 Anfossi P, Villa R, Montesissa C et al 1997 Intramuscular bioavailability of ketoprofen lysine salt in horses. Veterinary Quarterly 19 65-68 Avouac B, Teule M 1988 Ketoprofen the European experience. Journal of Clinical Pharmacology 28 S2-S7... 

The OAT proteins play a critical role in the excretion and detoxification of a wide variety of drugs, toxins, hormones and neurotransmitter metabolites. A number of common non-steroid anti-inflammatory drugs (NSAID), including acetyl salicylate and salicylate, acetaminophen, diclofenac, ibuprofen, ketoprofen, indomethacin, and naproxen, are substrates of one or more OAT isoforms, so that there can be significant interactions between NSAlDs and other drugs. The 3-lactam antibiotics (penicillins, cephalosporins and penems) and the antiviral nucleosides adefovir, cidofovir,... 

The results are in agreement with the recent release study of nonsteroidal drug ketoprofen [6]. Despite the fact that the ketoprofen release was studied by different techniques and therefore the release rate values are not comparable directly, the same tendency was observed. Additionally, it has been shown [34] that incorporation of ketoprofen does not alter the microemulsion system significantly however, its presence prevents the formation of stronger interaction and formation of gel-like structure in water rich region. It was also found out that stronger interactions between microemulsion components in W/O as well in the bicontinuous phase lead to slower ketoprofen release. Because of similar molecule structure of ibuprofen the same could be assumed also for it. We can conclude that release behavior of ibuprofen is influenced with the microstructure and can be predicted to a certain extent, using a combination of several tested methods for physical characterization of microemulsions. 

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