Technische Universität München

The Entrepreneurial University

Diuretics have the ability to increase urine production and secretion and are frequently used by athletes either to excrete the banned drug or to lose weight rapidly. However, urinary tract fluid losses caused by drug-induced diuresis may lead to intravascular volume depletion. Excessive diuretic therapy in combination with increased ephidrosis, usually leads to dehydration and hypovolemia, which is one of the major causes of hypokalemia.

Unlike medical patients, athletes do not retain excess water, thus the use of diuretics results in an abnormal and dangerous loss of water and electrolytes. Athletes with diuretic-induced dehydration, performing in heat, are more susceptible to heat exhaustion. Hypotension can be particularly troublesome sometimes. Use of diuretics commonly leads to low levels of body potassium. However, severe symptomatic hypokalemia is rare, while moderate levels of hypokalemia are common. Hypokalemia mainly causes disturbed neurological functioning and cardiac arrhythmias, even heart failure. Additionally, symptoms as muscle weakness and muscle cramps are common.

On the other hand, overuse of diuretics such as spironolactone, triamterene and amiloride may lead to extremely high potassium concentration in the blood. Hyperkalemia may lead to malignant arrhythmias. It is reported that serum potassium of 6.7 mmol/l may lead to a run of sustained ventricular tachycardia. Furthermore, most diuretics disturb the metabolism of uric acid and this can precipitate a painful attack of gout.

In general, all diuretics have the same side effects:
  • dehydration
  • hypovolemia
  • muscular cramps and
  • orthostatic hypotension.
Biochemical shifts in potassium levels (kaliemia) may be life threatening if strong modification is induced by diuretics. Side effects may also include dehydration, dizziness, cramps, headaches, nausea and kidney damage. Other side effects are excessive weight loss, low blood pressure, low or high blood potassium, heart rhythm disorders, systemic alkalosis, decreased muscular work, muscle cramps, increased blood uric acid, low blood sugar transient deafness (bumetanide, ethacrynic acid, furosemide), and aggravation of diabetes (thiazides).