Does acetylcysteine have an anticoagulant effect?

Fråga: Does acetylcysteine have an anticoagulant effect?

Sammanfattning: There is very little evidence that acetylcysteine treatment would have an anticoagulant effect.

Svar: This question has previously been discussed in Drugline (1). In a double blind study (2) of acetylcysteine in 64 Adult Respiratory Distress Syndrome (ARDS) patients it was found that the activity of antithrombin III was constant in the acetylcysteine group while it was increased in the control group. Also the prothrombin time was significantly decreased in the acetylcysteine group. The prothrombin time was significantly decreased and the plasma level of fibrinogen was significantly increased in the acetylcysteine group. However the results are difficult to interpret. A search in pharmacological handbooks and Medline gave nothing new. SWEDIS (The Swedish Drug Information System) presented one case of acetylcysteine possibly inducing reversible epistaxis, one case of naproxen or acetylcysteine possibly inducing increased antithrombin III time, three cases of increased anticoagulative effect of warfarin possibly by acetylcysteine and one case of decreased anticoagulative effect of warfarin possibly by acetylcysteine. No further information was found in pharmacological handbooks, Medline or Drugline. The Karolinska Hospital Coagulation Laboratory is not aware of any increased bleeding risk with acetylcysteine treatment nor any interaction between acetylcysteine and warfarin. It should be pointed out that this is an extensively used drug and very little evidence of an anticoagulant effect with acetylcysteine treatment has been found. 1 Drugline no 10042 (year 1993) 2 Jepsen S, Herlevsen P, Knudsen P, Bud MI, Klausen N-O: Antioxidant treatment with N-acetylcysteine during adult respiratory distress syndrome: A prospective, randomized, placebo-controlled study. Crit Care Med 1992; 20: 918-923