Active: Spironolactone. Aldactone is a diuretic and belongs to the subgroup of potassium- sparing diuretics.Spironolactone is an aldosterone antagonist. It inﬂuences the body’s own hormone, aldosterone, which accelerates the excretion of potassium and reduces the excretion of sodium and water.
Simplified, aldosterone regulates the endogenous water household. The higher the aldosterone level, the more water is stored in the body. The use of Aldactone results in a significant reduction in the aldosterone level so that the increases excretion of sodium and water occurs while, at the same time, potassium is re-absorbed. This also explains why Spironolactone is called a potassium-sparing sparing diuretic since it does not cause a loss of potassium like thiazides and furosemides do.
Athletes must strictly observe that during the use of Spironolactone no additional potassium is taken since this would cause a life threatening increase in the serum potassium level. Potassium-sparing diuretics have relatively low diuretic effects so that Aldactone can be called a mild diuretic. It is interesting to note that Spironolactone is also an anti-androgen since it reduces the androgen level. Female athletes take advantage of this characteristic by using it to reduce the virilization symptoms during steroid treatment or the symptoms after treatment. For this purpose Spironolactone is normally taken daily for 10 to 14 days, usually in a dose of 50 mg/day.
In men this could cause problems since the relationship of the androgen level to the estrogen level changes in favor of the latter. Thus, common side effects in men include pain in the nipples and breast swelling (gynecomastia).
Bodybuilders use Spironolactone almost exclusively during the last week before a competition. Since this causes neither a dramatic nor an immediately noticeable draining effect, it is usually taken over 5-6 days in a dosage of 2 tablets of 50 mg daily. Spironolactone should not be used to expediently drain water at the last minute. Both male and female athletes take it. The side effects of potassium-saving diuretics are relatively low compared to thiazides and furosemides. The main problems in men consist of gynecomastia and possible impotence. Side effects can be low blood pressure, muscle spasms, dizziness, gastrointestinal pain, vomiting, irregular pulse rate and fatigue. It is also significant to note that there is no significant increase in serum potassium level.