Drug General Information (ID: DDI0M6B1PJ)
Drug Name			Naproxen		Drug Info		Acetylsalicylic acid		Drug Info
Drug Type		Small molecule				Small molecule
Therapeutic Class		Nsaids/Analgesics				Analgesics
Structure

Mechanism of Naproxen-Acetylsalicylic acid Interaction (Severity Level: Moderate)
Increased risk of bleeding Click to Show/Hide Mechanism Graph
Drug Name		Naproxen				Acetylsalicylic acid
Mechanism		Risk of bleeding Antiplatelet effects				Risk of bleeding Antiplatelet
Key Mechanism Factor 1
		Factor Name		Bleeding
		Factor Description		Patients may be at risk for bleeding when the outcome of a disease or disease treatment confounds the standard mechanisms for maintaining hemostasis. Signs or symptoms of abnormal bleeding include: bleeding that takes a long time to stop (including nosebleeds, bleeding gums, bleeding from cuts and abrasions, and menstrual bleeding); severe unexplained bruising, or bruising that becomes larger; blood in the urine or stool, etc.
Mechanism Description		Increased risk of bleeding by the combination of Naproxen and Acetylsalicylic acid

Recommended Action
Management		Until more information is available, patients receiving low-dose aspirin for cardioprotection should avoid the regular use of NSAIDs including ibuprofen, indomethacin, naproxen, and tiaprofenic acid. Occasional, single use may be acceptable, as the risk from any attenuation of the antiplatelet effect of low-dose aspirin is likely to be minimal given the long-lasting effect of aspirin on platelets. If routine NSAID therapy is necessary, diclofenac may be a viable alternative. In the retrospective study implicating ibuprofen, 75 mg twice daily of delayed-release diclofenac did not interfere with the antiplatelet activity of aspirin. Other noninterfering alternatives for pain include acetaminophen, celecoxib, or narcotic analgesics. In any case, caution is advised whenever aspirin is combined with a NSAID due to the potential for additive GI toxicity. Patients should be advised to take the medications with food and to immediately report signs and symptoms of GI ulceration and bleeding such as abdominal pain, bloating, sudden dizziness or lightheadedness, nausea, vomiting, hematemesis, anorexia, and melena.

References
1	Concomitant use of ibuprofen and aspirin. J Pain Palliat Care Pharmacother 21 (2007): 73-4. [PMID: 17844731]
2	Schafer AI "Effects of nonsteroidal antiinflammatory drugs on platelet function and systemic hemostasis." J Clin Pharmacol 35 (1995): 209-19. [PMID: 7608308]
3	Wilner KD, Rushing M, Walden C, et al. "Celecoxib does not affect the antiplatelet activity of aspirin in healthy volunteers." J Clin Pharmacol 42 (2002): 1027-30. [PMID: 12211219]