Is there an increased risk of thromboembolism during treatment with spironolactone?/nA woman is tre

Fråga: Is there an increased risk of thromboembolism during treatment with spironolactone? A woman is treated with spironolactone 50 mg daily for aldosteronism and hypertension. The patient is also homozygous for APC-resistance.

Sammanfattning: Spironolactone has been widely used for many years and no clinical data could be found concerning an increased risk for thromboembolism. Spironolactone has antiandrogenic effects in men and antiestrogenic properties in experimental animals. On theoretical ground, these effects are not expected to increase the risk of thromboembolism.

Svar: Documentation concerning thromboembolism during spironolactone treatment is missing. WHO´s adverse drug reactions database, Intdis, revealed one case of thrombosis during treatment with spironolactone. However, this report was judged as unclassifiable because of limited information (1).

Spironolactone has no known effects on the haemostasis. Spironolactone causes a number of endocrine changes including gynecomastia, menstrual irregularity, impotence and loss of libido. These effects have been attributed to interference with testosterone synthesis rather than estrogenic properties (2). Experimental data from immature female rats has shown that spironolactone inhibits the binding of oestradiol to receptors in the uterine and mammary cytosols, suggesting an antioestrogenic effect (3).