Summary
The effects of treatment with danazol (600 mg daily) on haemostatic and haematological
function were investigated in 18 pre-menopausal women with endometriosis. Blood samples
were taken at 2 pre-treatment visits, at 6, 12 and 24 weeks on treatment, and at 6
weeks after discontinuation of the drug. Haemoglobin, red cell count, haematocrit
and platelet count all rose significantly during treatment with danazol (p <0.01 vs.
baseline). Plasma fibrinogen levels fell significantly (p <0.01), while whole blood
viscosity increased during treatment and remained significantly elevated at follow-up.
The prothrombin time shortened, but remained within normal limits, and there were
no significant changes in factor VII:C, Vila, or fibrinopeptide A. No significant
changes were found in platelet function. Plasma B-beta 15-42 increased significantly.
Functional levels of protein C, protein S, and antithrombin III, all rose significantly,
above the normal range, while C4b-binding protein levels fell. We conclude that the
observed changes in coagulation inhibitors and fibrinolytic activity may be considered
beneficial in the context of venous thromboembolism. The rheological effects, however,
indicate a degree of caution in the use of the drug in individuals considered to be
at risk from arterial cardiovascular disease.
