NSAIDs Quinolones

NSAIDs QUINOLONES Reports of convulsions when NSAIDs are added to quinolones in epileptic patients Unknown Take care in co administering epileptics and NSAIDs in epileptic patients... 

Clinically important, potentially hazardous interactions with cyclosporine, lithium, methotrexate, mifepristone, NSAIDs, quinolones, salicylates... 

Mannino S, Garcia-Rodriguez LA, Jick SS, NSAIDs, quinolones and convulsions an epidemiological approach. Post Marketing Surveillance (1992) 6, 119-28,... 

Drugs implicated 3-Lactams other antibacterials NMBDs some NSAIDs quinolones mAbs proton pump inhib s P-Lactams quinine quinidine sulfonamides NSAIDs procainamide gold carbamazepine propylthiouracil ticlopidine P-Lactams ciprofloxacin sulfonamides lincomycin tetracycline NSAIDs carbamazepine allopurinol gold methyldopa mAbs NSAIDs p-lactams othCT antibiotics anti-convulsants antimalarials local anesthetics barbiturates quinolones dapsone... 

QUINOLONES NS AIDs Reports of convulsions when NSAIDs were added to quinolones in those with epilepsy Unknown Care in co-administering antiepileptics and NSAIDs in patients with epilepsy... 

Quinolone antimicrobials convulsions may occur if NSAIDs are co-administered. 

A number of cases of convulsions have been seen in Japanese patients given fenbufen with enoxacin, and there is also one possible case involving ofloxacin. Use of these particular drugs together should be avoided. Normally no interaction seems to occur with most quinolones and NSAIDs, except where there is a predisposition to convulsive episodes. Isolated cases of convulsions, other neurological toxicity or skin eruptions have been seen when ciprofloxacin was given with indometacin, mefenamic acid or naproxen. These appear to be very rare events. 

Not fully understood. Convulsions have occurred in a few patients taking quinolones alone, some of whom were epileptics and some of whom were not (see Antiepileptics + Quinolones , p.522). Experiments in mice have shown that quinolones competitively inhibit the binding of gamma-amino butyric acid (GABA) to its receptors. GABA is an inhibitory transmitter in the CNS, which is believed to be involved in the control of convulsive activity. Enoxacin and fenbufen are known to affect the GABA receptor site in the hippocampus and frontal cortex of mice, which is associated with convulsive activity.It could be that, if and when an interaction occurs, the NSAID simply lowers the amount of quinolone needed to precipitate convulsions in already susceptible individuals. 

Reports of adverse interactions between other quinolones and NSAIDs are extremely rare. The general warning about convulsions with quinolones and NSAIDs issued by the CSM in the seems to be an extrapolation from the interaction between enoxacin and fenbufen, and from some animal experiments. In addition to the data cited above, an epidemiological study of 856 users of quinolones (ciprofloxacin, enoxacin, nalidixic acid) and a range of NSAIDs found no cases of convulsions. The overall picture would therefore seem to be that although a potential for interaction exists, the risk is very small indeed and normally there would seem to be little reason for most patients taking quinolones to avoid NSAIDs. Epileptic patients are a possible exception (see Antiepileptics H- Quinolones , p.522) and it would seem prudent to avoid quinolones and NSAIDs wherever possible in these patients. 

Drugs well known to cause type I reactions include penicillins, cephalosporins, neuromuscular blocking drugs, some NSAIDs, monoclonal antibodies, quinolones, and proton pump inhibitors. 

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