Interactions between vioxx(rofecoxib) and Acetylsalicylic acid (aspirin)
aspirin and rofecoxib (Moderate Drug-Drug)
MONITOR: The combined use of low-dose or high-dose aspirin with other nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the potential for serious gastrointestinal (GI) toxicity, including inflammation, bleeding, ulceration, and perforation. Aspirin at anti-inflammatory dosages or higher may also decrease the plasma concentrations of many NSAIDs. The decreases have ranged from none or small (piroxicam, naproxen, tolmetin) to substantial (flurbiprofen, ibuprofen). Meloxicam AUC and plasma levels tended to increase by 10% and 24%, respectively. However, the therapeutic response does not appear to be affected. Investigators theorize that aspirin may displace NSAIDs from plasma protein binding sites, resulting in increased concentration of unbound, or free, drug available for clearance. The increase in NSAID free fraction, and possibly some contributory anti-inflammatory effect from aspirin, may account for the lack of overall effect on therapeutic response.
MANAGEMENT: Caution is advised if aspirin, particularly at anti-inflammatory dosages, is used with other NSAIDs. Concomitant administration is not recommended by many NSAID manufacturers due to the risk of adverse effects. During concomitant therapy, patients should be advised to take the medications with food and to immediately report signs and symptoms of GI ulceration and bleeding such as severe abdominal pain, dizziness, lightheadedness, and the appearance of black, tarry stools.
