Diflunisal pharmacokinetics

Eriksson LO, Wahlin-Boll E, Odar-Cederlof I, Lindholm L, Melander A. Influence of renal failure, rheumatoid arthritis and old age on the pharmacokinetics of diflunisal. Eur J Clin Pharmacol 1989 36 165-174. 

Oral contraceptives increase diflunisal clearance in women, but only to the level normally seen in men. One study showed modestly reduced levels of ibuprofen with oral contraceptives, but another study did not. Oral contraceptives reduced the levels of aspirin, but not phenylbutazone. There are no clinically relevant changes in the pharmacokinetics of oxaprozin with conjugated oestrogens. 

The concurrent use of two or more NSAIDs increases the risk of gastrointestinai damage. Diflunisal raises serum indometacin levels about twofold but does not affect naproxen levels. The concurrent use of indometacin and flurbiprofen does not appear to affect the pharmacokinetics of either drug. Floctafenine does not alter diclofenac levels. Indometacin caused renal impairment in a patient recovering from phenylbutazone-induced acute renal failure. 

Van Hecken Verbesselt R, Tjandra-Maga TB, De Schepper PJ. Pharmacokinetic interaction between indomethacin and diflunisal. EurJ Clin Pharmacol (1989) 36, 507-12. 

Paracetamol levels are increased by diflunisal. Aspirin, diclofenac, nabumetone and sulindac pharmacokinetics do not appear to be affected by paracetamol. There is no pharmacokinetic interaction between ibuprofen and paracetamol. Propacetamol, and possibly paracetamol, increase the antiplatelet effects of diclofenac, although the evidence is limited and the clinical relevance of this is uncertain. 

Tempero KF, Cirillo VJ, Steelman SL. Diflunisal a review of pharmacokinetic and pharmacodynamic properties, drug interactions, and special tolerabilily studies in humans. BrJ Clin Pharmacol 911) 4, 31S-36S. 

Diflunisal had no effects on the pharmacokinetics of triamterene in healthy subjects, but the plasma AUC of an active metabolite, p-hydroxy-triamterene was increased by more than fourfold. ... 

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