Diuretics are drugs that increase the rate of urination, and promote the elimination of water and electrolytes such as sodium, chlorine and potassium. Most of the clinical uses of diuretics are aimed at reducing the amount of extracellular fluid by eliminating sodium chloride. The physiological need for these interventions is often dictated by the fact that through diet, due to excessive salt intake, the body tends to accumulate sodium and the subsequent accumulation of fluids incompatible with life, which can lead to cardiovascular and respiratory disorders.
Diuretics are used for edema, hypertension and heart failure.
The class of diuretics can be divided into different categories, characterized by different sites of action, different chemical structures and different effects on the body. excretion of potassium.
Carbonic anhydrase inhibitors (acetazolamide, doklorfenamide, etc.) act by inhibiting the activity of carbonic anhydrase, blocking the reabsorption of NaHCO in the proximal canal. with a subsequent increase in urinary excretion of HCO3 , , Cl , K +> and Na +
Osmotic diuretics (glycerin, mannitol, urea, etc.) filter out these substances and are weakly absorbed again and being hydrophilic, they resemble water, promoting its elimination, they act to a limited extent on electrolytes.
Loop diuretics (furosemide, bumetanide, indapamide, torasemide, etc.) act by inhibiting the symptom Na + , K , 2Cl , in the loop of Henle which are therefore eliminated, which also promotes the elimination of water, They are especially effective and are also called potent diuretics.
Thiazide diuretics (benzothiazide, chlorothiazide, hydrochlorothiazide, altizide, etc.) act by suppressing NaCl transport in the distal tubules.
Potassium screensavers, (triamterene, amiloride, etc.) promote NaCl removal and reduce K loss by blocking the sodium channel.
Aldosterone antagonists, (spironolactone, canrenone, etc.) act by inhibiting the binding of aldosterone to its receptor, therefore aldosterone is no longer able to fulfill its mineralocorticoid function, which promotes fluid retention and increased pressure.
Diuretics should be immediately made clear that they do not promote any type of work, on the contrary, electrolyte imbalances can lead to a decrease in the ability of muscle contraction, can lead to seizures, can alter heat dissipation.
Side effects that can occur after diuretics include dehydration, hypokalemia, hyponatremia, metabolic acidosis, hypovolemia, and hyperuricemia. If dehydration is particularly severe, it can cause hypotension, dizziness, drowsiness, confusion, movement difficulties, palpitations, increased blood density with the risk of dithrombosis and cardiac arrest, kidney failure and impairment with possible kidney collapse, coma, and death from complications. cardiac and / or cerebral (edema, ischemia, etc.). Therefore, the use of diuretics is extremely risky for an athlete who, in conditions of electrolyte imbalance, undergoes intense physical activity and increases this imbalance, increasing the risk of complications and side effects.
Despite all these risks, the use of diuretics is especially common in sports, and there are numerous cases of positive doping tests for diuretics, in particular the most common is furosemide (Lasix).
Diuretics are used by athletes for several reasons:
- Weight loss promotion for disciplines representing weight classes
- Concealing the use of other prohibited substances by facilitating their excretion in urine
- Weight loss in sports where the body has to move quickly (swim, jump, etc.)
- Dehydrate the body to make it aesthetically drier and more pleasing in disciplines where athletic appearance is important, primarily bodybuilding and related activities, as well as dancing
In 2008, diuretics accounted for about 8% of all anti-doping tests, in 2009 – 5.5%, and in 2010 – more than 7%. All classes of diuretics were detected by tests, and the most common actives were hydrochlorothiazide and furosemide, with a frequency clearly higher than other diuretics.
The total number of cases has been growing over the years, but this trend is likely due to improved detection methods.
The Anti-Doping Code allows for the use of diuretics by derogation at the request of athletes and doctors for therapeutic purposes by providing appropriate medical records For example, in the case of hypertension. However, if the athlete’s urine contains a diuretic in combination with another exogenous substance on the Prohibited List, the test is considered positive because it is assumed that actual athletics use is motivated by a desire to disguise another active ingredient.
Several studies (Caldwell) that compared the effects of different weight loss methods: exercise, sauna and diuretics; showed a decrease of 2.3 ± 0.8 kg after training, 3.5 ± 0.8 kg after sauna and 3.1 ± 0.8 kg after the introduction of furosemide. The same study showed that the change in plasma volume in athletes is -0.9% after exercise, -10.3% after sauna and -14.1% after administration of furosemide. These data show that the effect of diuretics to promote weight loss , leads to an increase in health risk, because a decrease in plasma volume is associated with the risk of ischemic events and possible circulatory disorders, especially during physical exertion, as well as a decrease in the athlete’s ability to maintain work and, consequently, loss of sports performance.
Most diuretics, with the exception of potassium-sparing drugs, lead to hypokalemia followed by muscle spasms and possible cardiac arrhythmias, other risks that the Athlete uses these substances.
On the other hand, overuse of potassium-sparing diuretics can lead to hyperkalemia and therefore put athletes at risk for malignant arrhythmias.
Further studies on distance runners (Armb) have confirmed that diuretics decrease performance, and this effect is related to the amount of weight (fluid) lost, in fact at higher dosages. resulting in more dependent losses, more performance degradation. In addition, the type of performance also determines the degree of the effect, since the drop in performance was greater at longer distances.
Other studies of wrestlers (Caldwell) have shown similar results: diuretics impair overall athletic performance. As mentioned, dehydration alters aerobic capacity, muscle contraction strength, and decreases metabolic efficiency, with negative effects on any type of performance. In addition, there is a risk that diuretic abuse will lead to changes in the glomeruli of renal filtration with consequences for renal function itself, these effects also depend on the mechanism of action of the different classes of diuretics.
Finally, insufficient data needs to be added to establish the possible effect of long-term diuretic treatment on performance.
For many of the reasons listed, the disadvantages of taking diuretics far outweigh the o The potential benefits of weight loss and urinary dilution.