Diuretic compounds can be natural or pharmaceutical. They affect the amount of urine output mainly by changing the re-uptake of water in the kidneys.
They can work quickly or slowly all day long. They can be brief in action or have an effect for many hours. They are fairly safe substances given to countless senior citizens to lower blood pressure. They deplete plasma volume. Taken in abundance they can cause serious electrolyte disturbances that affect both skeletal and cardiac muscle. Their abuse is legendary.
Competitors use diuretics often alone without any of the above techniques of manipulation. For extreme cases requiring upwards of 13-15 pounds of weight loss diuretics are a viable option when used in conjunction with other methods. For weight loss under 10 pounds they should not be considered. Most diuretics have powerful actions and consequences. Admittedly, it is easier to take a pill than to restrict water intake for a day or so. But water restriction is not as acute and not nearly as easy to overdo.
Most athletes save diuretics for the most challenging of cuts. They keep an ace up their sleeve to go to when other methods seem to have little more to offer. Also, most diuretics that have noticeable effect are drugs which appear on the banned list of substances of the International Olympic Committee.
But this is not to become an ethical decision. Athletes use diuretics. I am only outlining the methods that have been used.
The effectiveness of a diuretic depends on the state of hydration and specifically the blood volume. I have been witness to an athlete who injected 120 mg. of the diuretic Lasix (furosimide) and was still unable to urinate for six hours. Lasix has a peak effect that starts one hour after taking it, lasts quite strongly for about an hour and then continues to work less and less for about 2-3 more hours. The injections can cause diuresis within 15-20 minutes. If and athlete takes a normal dose (40 mg.) it can be expected that they will urinate 2-4 pounds out quite soon an certainly within 2 hours. This particular athlete was so dehydrated when the Lasix was taken that even a heavy dose did not produce diuresis. The athlete had already, and recently, depleted his plasma volume and when the drug hit, there was nobody home. One can't get blood from a stone and one can't use diuretics when the blood volume is low.
A normal dose of Lasix is 40 mg. and if blood volume is reasonable will produce substantial weight loss. 2-4 pounds can easily be expected but results vary on a few other factors such as the body's total sodium content. It is not uncommon to see athletes use more. But it can not be said that for every 40 mg. the yield will be 4 more pounds. In fact using 80 mg. likely will only yield 5-6 pounds. If an athlete is very well hydrated and has lots of sodium 40 mg. could yield 6-8 pounds. If the athlete is already partially dehydrated 40 mg. may only give 2 pounds. Since there is no sure amount, as usual, trial and error is required.
Diuretics have different classes and operate in slightly different ways. Some can deplete the body of potassium while others will spare potassium. Athletes must be very aware of what type of drug they are using and how that particular drug affects electrolytes. If an athlete were to use a potassium-sparing drug and then supplement the diet with potassium tablets in an effort to avoid cramping, then serious unwanted cardiac effects could result. With other drugs that deplete potassium, adding potassium to the diet is a sound idea. The athlete must know what it is exactly they are doing and consult with a physician or health care professional. (There are just too many different drugs to outline here.).
I have seen it as common practice to combine different diuretics to increase the effect. While it is true that some diuretics come in combination as prepared from the manufacturer, this is generally not a safe endeavor. Almost surely more harm than good can come from it. Athletes who rely solely on diuretics for cutting weight are prone to combine drugs. Athletes who use a variety of methods to drop body weight find that a single diuretic drug in a tailored dose is completely adequate.
A drug that is very popular now is Bumex (bumetanide). It is extremely powerful and a normal dose of just 1-2 mg. will yield the same effects as 40-60 mg. of Lasix. The onset is in an hour after swallowing and lasts about 50-80 minutes with its strongest effect. It will continue to work for several hours but much less noticeably. It is more appealing because the athlete has rapid onset short action and relatively quick removal of the drug from the body. Also the athlete can put a much, much smaller amount of drug into the body (2 mg. vs. 40-60 mg. in the case of Lasix) and that is always a more elegant option.
Drugs often seen arranged from weakest to strongest are Aldact one (spironalactone), Diamox (acetazomide), Lasix (furosemide), and Bumex (bumetanide) but this list is far from comprehensive. Although some general expectations of water loss from normal dosages were estimated above, there are too many factors to call it in hard fast numbers. Every athlete must endure recorded trials and come to an understanding of the dosage as it relates to the overall hydration state and timing of the methods.
Timing is a big factor. For example, if an athlete were to use a powerful diuretic like Lasix at 10:00 a.m. buy 12:00 the major effect would have taken place. The water lost is mainly from the fluid compartment of the blood. If the athlete were to repeat another dose at 1:00 p.m. there would be little change in body weight and there is a very serious risk of upsetting things. There is no more fluid available for loss from that compartment at this time. But if the athlete were to wait until 8:00 p.m. or later, the repeated dose would have an attenuated but similar effect as earlier. This is because the body has had time to begin to replenish the plasma volume from the water held in the interstitial space. The blood is de-hydrated and the interstitium suffers dehydration. The plasma volume can now supply fluid for diuresis. If the athlete attempts a repeated dose too close in time to the first, nothing will happen and all the risks will be greatly elevated. Timing is critical to success and the minimization of risk.
The electrolyte state of the athlete at the time of diuretic use can also can have great impact on results. If an athlete were to sodium deplete for several days and administer Lasix at that time the results would be attenuated. Lasix can't work right if there is no sodium to drive out of the body. Its method of action is to cause sodium (and potassium) to be excreted. The water just follows along with the sodium. If there is a shortage of sodium to push out, the diuresis will be much less.
If an athlete has a high blood potassium to begin with and takes a potassium-sparing diuretic, intensely painful cramping can occur which can be life threatening. Even an upset in the sodium and plasma volume can cause this, not by changing the amount of potassium, but by changing its relative concentration.
I hope the "big picture" is starting to develop here. There are simply too many variables to give concrete estimations of exactly how a diuretic will work for any individual athlete unless all the variables are known at that time and in that state. Everything is ballpark. But a responsible athlete will go to the lengths of diligently making notes and undergoing mild trials to find suitable regimes.
No advice from anyone is good advice. Things like a blood test taking special note of electrolytes (potassium in particular) and hematocrit (thickness of the blood) before diuresis begins, and constant measurement of blood pressure throughout the process will provide valuable information and steer the decisions about dosage and type of diuretic.
A diuretic should not be considered if the pre-cutting blood work shows the potassium level to be above 5 mEQ. A diuretic should not be an option if blood pressure is below 100/60. The hematocrit should not be allowed to rise above 60. Although it is unlikely you will have access to serial blood draws you can get at least a pre- and post. It is arrangeable to have a draw right when stepping off the scale or within a few minutes at a nearby doctor's office. This will give the athlete knowledge that can be used to modify the program to increase safety and efficacy in the future.
The use of an aspirin a day for two weeks prior to dehydrating is said to be a good idea. It has an effect to inhibit blood clotting. In a very dehydrated state (even a very brief one such as cutting weight) there is an increased risk of cerebrovascular incident or stroke. When hermatocrit is at its highest the risk is greatest. The aspirin makes it less likely that a clot will form and reduces this risk. Any reduction is welcomed, however small.
Diuretic use is dicey but commonly occurs with no ill effects. However, improper or foolish abuse can lead to the most serious of side effects. They also carry the biggest risk to impeded performance. An athlete may escape health concerns but do poorly in the competition. Great care must be taken by athletes choosing this route. A physician should always be consulted before an athlete undergoes any addition of pharmaceuticals to their normal state.
*Potential Loss: varies
*Duration: Extremely short, several hours at most
*Effort Level: Almost none!
- To health: high, cardiac arrest, stroke and all associated dehydration risks. Also drug interaction risks with everyday meds.
- To performance: depletion in this way is notorious for sabotaging performance. Many lifters undermine themselves by excessive reliance on diuretics.
*Up Side: Easy and when done with caution, allows great loss of weight
*Down Side: Involves the use of drugs. Although there are some natural alternatives, they are very weak in comparison. The naturals can help in a fully hydrated state to cut some water, but prove to be too mild to affect any change in a partially dehydrated state.
Next: Synthesis of Methods.