Drug Interactions between feverfew and Halfprin

Theoretically, feverfew extracts may potentiate the effects of anticoagulants, platelet inhibitors, and thrombolytic agents, possibly increasing the risk of bleeding. In vitro studies have shown feverfew to interfere with hemostasis and platelet aggregation by neutralizing platelet sulfhydryl groups as well as preventing prostaglandin synthesis. However, bleeding complications and interactions with hematologic agents have not been reported. Moreover, pharmacologic effects may be highly variable due to inconsistencies in formulation and potency of commercial herbal products. Patients should consult a healthcare provider before taking any herbal or alternative medicine. In patients who have used feverfew extensively prior to receiving anticoagulation, antiplatelet, or thrombolytic therapy, the potential for an interaction should be considered. Clinical and laboratory observation for hematologic complications is recommended. Patients should be advised to promptly report any signs of bleeding to their physician, including pain, swelling, headache, dizziness, weakness, prolonged bleeding from cuts, increased menstrual flow, vaginal bleeding, nosebleeds, bleeding of gums from brushing, unusual bleeding or bruising, red or brown urine, or red or black stools.

Switch to consumer interaction data