Reports suggest that nonsteroidal anti-inflammatory drugs may diminish the antihypertensive effect of ACE-inhibitors. This interaction should be given consideration in patients taking nonsteroidal anti-inflammatory drugs concomitantly with ACE-inhibitors.
The effects of warfarin and NSAIDs on GI bleeding are synergistic, such that users of both drugs together have a risk of serious GI bleeding higher than users of either drug alone. The physician should be cautious when administering ASAID to patients taking warfarin or other anticoagulants.
Concurrent administration of aspirin lowers serum flurbiprofen concentrations (see CLINICAL PHARMACOLOGY, Drug-Drug Interactions). The clinical significance of this interaction is not known; however, as with other NSAIDs, concomitant administration of flurbiprofen and aspirin is not generally recommended because of the potential for increased adverse effects.
Beta-adrenergic blocking agents
Flurbiprofen attenuated the hypotensive effect of propranolol but not atenolol (see CLINICAL PHARMACOLOGY, Drug-Drug Interactions). The mechanism underlying this interference is unknown. Patients taking both flurbiprofen and a beta-blocker should be monitored to ensure that a satisfactory hypotensive effect is achieved.
Clinical studies, as well as post marketing observations, have shown that ANSAID can reduce the natriuretic effect-of furosemide and thiazides in some patients. This response has been attributed to inhibition of renal prostaglandin synthesis. During concomitant therapy with NSAIDs, the patient should be observed closely for signs of renal failure (see WARNINGS, Renal Effects), as well as diuretic efficacy.
NSAIDs have produced an elevation of plasma lithium levels and a reduction in renal lithium clearance. The mean minimum lithium concentration increased 15% and the renal clearance was decreased by approximately 20%.
These effects have been attributed to inhibition of renal prostaglandin synthesis by the nonsteroidal anti-inflammatory drug. Thus, when nonsteroidal anti-inflammatory drugs and lithium are administered concurrently, subjects should be observed carefully for signs of lithium toxicity.
Nonsteroidal anti-inflammatory drugs have been reported to competitively inhibit methotrexate accumulation in rabbit kidney slices. This may indicate that they could enhance the toxicity of methotrexate. Caution should be used when nonsteroidal anti-inflammatory drugs are administered concomitantly with methotrexate.