Does Arcon Tisane interact with Waran (warfarin)?/nAn 82-year-old woman uses Arcon Tisane against l

Fråga: Does Arcon Tisane interact with Waran (warfarin)?

An 82-year-old woman uses Arcon Tisane against loss of hair. The physician is wondering if this natural product interacts with warfarin. Accordning to the physician the patient has the intention to take the drug.

Sammanfattning: Theoretically fenugreek may have an anticoagulant effect, according to the coumarin derivate content, although the clinical importance is unknown. There is one case report of a possible interaction between warfarin and fenugreek. Caution is advisable in patients using this combination.

Svar: Arcon Tisane is a natural product used to treat loss of hair. The capsules contain extract from fenugreek Trigonella foenum-graecum (bockhornsklöver in Swedish) seed, nicotinic acid, calcium pantothenate, vitamin B2, vitamin B6 and folic acid (1). Fenugreek seeds contain, among other constituents, a coumarin derivate, which may prolong blood coagulation time. Any other anticoagulant effect of fenugreek is not documented. In a monograph of fenugreek caution is advisable to patients on anticoagulant therapy (2).

There is one case report available where a possible interaction between fenugreek and warfarin has been reported. A 67-year-old woman was treated with warfarin. Her international normalized ratio (INR) was in therapeutic range during the first year of treatment. Higher INR was later measured at a routine control. The women told her physician that she hade taken boldo, another herbal drug, and fenugreek during the last weeks. Boldo and fenugreek were withdrawn and one week later the INR was normalized. The patient started using the herbal drugs again and the INR increased. Since the woman wanted to use the herbal drugs the warfarin dose was reduced by approximately 15% and INR were maintained at therapeutic level (3). 1 Mattila Hälsa http://www.mattila.se/halsa.htm (cited 2003-03-14) 2 Barnes J, Anderson LA, Phillipson JD. Herbal medicines. A guide for health care professionals. 2nd ed. London: The Pharmaceutical Press; 2002 3 Lambert J-P, Cormier J. Potential interaction between warfarin and boldo-fenugreek. Pharmacotherapy 2001;21:509-12.