Diuretics are therapeutic agents that are used to increase the rate of urine flow, sodium and electrolytes excretion in order to adjust the volume and composition of body fluids or to eliminate excess of fluids from tissues .They are used in clinical therapy for the treatment of various diseases and syndromes, including hypertension, heart failure, liver cirrhosis, renal failure, kidney and lung diseases. 
Diuretics are banned in sports because they can be used by athletes for two primary reasons. First, their potent ability to remove water from the body can cause a rapid weight loss that can be required to meet a weight category in sporting events (wrestling, Olympic weight lifting, boxing). Second, they can be used to mask the administration of other doping agents by reducing their concentration in urine primarily because of an increase in urine volume. 
Furosemide is a powerful diuretic, available both in injectable and per os form.
Oral furosemide can be administered in the form of tablets or oral solution. Intravenous furosemide is twice as potent as oral furosemide.Furosemide is of immediate action and flushes urine within twenty minutes of oral intake. The terminal half-life of the drug is approximately two hours and total time of therapeutic effect is six to eight hours. Furosemideworks at the loop of Henle of kidney, inhibiting the sodium-potassium-chloride pump and leading to increased diuresis and natriuresis (increased sodium loss). The drug also induces renal synthesis of prostaglandins, which contributes to its renal action. 
Adverse effects are all correlated to fluid and electrolyte imbalance and hypovolemia. They include hyponatremia and/or extracellular fluid volume depletion (associated with hypotension, circulatory collapse and thromboembolic episodes), hypokalemia (which induces cardiac arrhythmias), hypomagnesemia which is likely to cause cramps and metabolic alkalosis, hyperuricemia (occasionally leading to gout) and hyperglycemia. Furthermore, they increase plasma levels of low-density lipoprotein cholesterol and triglycerides while decreasing plasma levels of high-density lipoprotein cholesterol. 
On the contrary, spironolactone is a potassium sparing diuretic. It belongs to the aldosterone inhibitors, a class of diuretics which antagonize the actions of aldosterone at the distal segment of the distal tubule.
Aldosterone is a hormone that belongs to the mineralocorticoids and is secreted by the adrenal cortex. It influences the reabsorption of sodium and excretion of potassium of the kidney, thus increasing water retention, blood pressure and blood volume.  Because potassium is the principal intracellular ion, its retention (by spirolactone’s action), will contribute to a better cellular volume, positively affecting the maintenance of the cellular size. Aldosterone plays an important role in the last week before a bodybuilding contest.
In order to inhibit aldosterone and eliminating water retention, we trick the body with an intentional increased intake of sodium chloride (table salt). This apparently will suppress any sodium retention the following days. Usually we quit from extra sodium intake, the very last day of glycogen depletion, just before the carb loading phase.
Abuse of spironolactone might lead to life threatening side effects, due to dramatic elevation of potassium (hyperkalemia) and metabolic acidosis. Myocardium is quite sensitive to this metabolic imbalance and can easily undergo severe arrhythmias (ventricular tachycardia, fibrillation) or even cardiac arrest (Mohamad Benaziza 1993).ECG changes in a patient with hyperkalemia are an ominous portent of potentially fatal arrhythmias.
The fact that the adrenal cortex produces a fair amount of dehydroepiandrosterone (DHEA), it is understandable, that abuse of spironolactone will lead to dose-dependent gynecomastia.  The anti-androgenic property of spironolactone (breast tenderness and enlargement) is even more apparent in women who lack the gonads (testicles) and substantially their testosterone is producedby the ovaries and adrenals. Women use spironolactone in order to reduce the aesthetic androgenic side effects of androgenic anabolic steroids (AAS), specifically hirsutism. Spironolactone acts suspensively on the steroid hormone synthesis and leads to hypogonadism with decreased sperm count and motility (FSH). Spironolactone is not of immediate action and stable concentrations are achieved within almost three days of treatment initiation. For better metabolism, the dosage should be splitted into am/pm timing. The appropriate timing for spironolactone’s use would be the very first day of carb depletion phase. Potassium rich foods (bananas or potatoes) are strictly prohibited. Spironolactone should get gradually reduced in order to avoid any possible rebound effect. The most efficient method in order to achieve the best results of diuretics should be the combination of potassium sparing and non-potassium sparing diuretics, hence spironolactone and furosemide. However, dosages should be reduced to half.
Diuretics are extremely dangerous substances, responsible of hypovolemia and dehydration, spasms of striated muscles (cramps),loss of coordination and balance, hypotension (a drop of systemic blood pressure).All diuretics except the potassium-sparing agents increase kaliuresis, accelerating the depletion of intracellular potassium. The resultant hypokaliemia can lead to severe cardiac arrhythmias secondary to electrolyte shifts/losses. On the other hand, overuse of potassium-sparing diuretics such as spironolactone, can lead to hyperkalaemia and consequently may expose athletes to malignant arrhythmias. 
A notable example of the cardiovascular collapse caused by abuse of diuretics was the tragic death of ‘’the giant killer’’, Arab Mohamed Benaziza (Momo) at the Dutch grand prix in 1993.Not only he abused spironolactone, but he also quitted from water intake and consumed clenbuterol in powder form, according to his close friend, Sammir Bannout.
Furthermore, diuretics are considered one of the most implicated classes regarding sexual dysfunction, particularly on erectile function,ejaculationand libido (mainly thiazide diuretics and spironolactone). Spironolactone has a tendency to produce undesirable sexual adverse events; at the standard dose, breast tenderness, gynaecomastia and erectile dysfunction can occur in men, whereas menstrual abnormalities may occur in premenopausal women. 
Diuretics are preferably used before night sleep, in order to avoid any possible fainting episode, due to hypotension. Potatoes and bananas, rich in potassium, can help in case of hypokalemia,while caffeine and alcohol are strictly prohibited (diuretic effect).
In bodybuilding diuretics are prohibited strictly during glycogen depletion phase, or any other period of the pre-contest preparation, apart from the carbohydrate loading phase to avoid the risk of possible water retention under the skin. In the week prior to competition bodybuilders follow tapering strategies to increase “muscle fullness”, by maximizing muscle glycogen content in order to obtain a dry and harder look, by minimizing subcutaneous water film under the skin  For those who wish to use furosemide, they have to consume calcium and magnesium from supplementary sources, in combination with carbohydrates rich in potassium, such as baked potato and banana. Muscles are unable to flex and pump, without proper electrolyte balance. Spironolactone, unlike furosemide, is responsible for keeping sarcoplasm’s volemia. This reflects to the external appearance of the bodybuilder, where his muscles are toned, able to contract. On the contrary, furosemide by flushing away all electrolytes from the muscle’s cytoplasm and potassium in particular, will lead to the characteristic flat, drained and empty look of the muscles.
Potassium is the main intracellular electrolyte and significant for keeping cell’s volume. The tricky part with spironolactone comes the day before the show, when serum potassium is high and switch to furosemide is an obligatory thing. Furosemide use will flush the extra potassium, in order not to be dangerously increased into the blood stream.
The morning of the contest, in case there is still water retention, the combination of a moderate dose of furosemide (10mg) along with spironolactone (12.5mg), is a safe way to eliminate extra water. Note that dehydrated muscles are not capable of proper contraction.In such cases, calcium tablets and liquid magnesium are good choices.
The sport of bodybuilding involves a risk, a craze, a vanity, all of which pose dangers in the long term, so exaggeration and the thought that more is bette is not panacea and does not necessarily guarantee success. Side effects of a particular substance are dependent on various parameters, such as age, time of abuse, dosage, combination of performance enhancing drugs (PED’s), life style, proper nutrition and supplementation, medical prevention rules and family history. In particular, polypharmacy stacking abuse is widely developed among bodybuilders to enhance muscle hypertrophy,burn fat, speed recovery and prevent the effects of overtraining, increase training intensity and aggressiveness, control fat, body water, and appetite.Anabolic androgenic steroids(AAS)combined with diuretics, anti-estrogens, stimulants,alcohol, tobacco, narcotics, and other medications can increase the risk for serious cardiovascular events.One of the most dangerous drugs in bodybuilding is diuretics and can lead respectively to lethalhypovolemic shock and severe heart arrhythmia. In fact, diuretics have been anecdotally associated with the death of some bodybuilders and their misuse and abuse also imposes an imminent risk to the bodybuilders’ health.
Personally,as a former competitive bodybuilder and champion,i used three different types of diuretics (Lasix,Aldactone,Moduretic) in each session of my athletic carrier (00,09,10,13). Both times i managed to win (2000,2009) i faced the ugly side of hypovolemia (low blood pressure, fainting) and muscle spasm (rectus abdominis).Diuretics can make the difference between two athletes with equal subcutaneous body fat.However the price of their use can jeopardize the whole efford and quit the show,while they are useless in case body fat levels are not under five to six percent.
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