Lasix (Furosemide)



Furosemide, sold under the popular brand name Lasix  is not an anabolic steroid or a steroid of any type but a loop diuretic designed to treat conditions that cause edema such as high hypertension or congestive heart failure. This is the primary purpose of Lasix to treat severe edema but as medications often do a place in the performance enhancing world has been found. It shouldn’t be too hard to see why this is; the idea behind Lasix is simple, to remove excess fluid and the same principle can be applied in an athlete who uses the medication. While there are athletes from a host of fields who use the medication by-in-large the majority will be competitive bodybuilders. Bodybuilders do not use the substance year round but only a day or two before a competition as this is when they are trying to rid themselves of every last drop of water in their body possible.

There’s no question, there are few diuretics that will remove the last bit of water like Lasix will and perform the job in a very potent way. However, the power is extreme and can be too powerful as we will see and because of this most bodybuilders will be best served looking for another more suitable option.

In the performance enhancing world it is rather common, although in recent years popularity has begun to fall in favor of other options. While Lasix definitely has a long standing history in competitive bodybuilding it has a place in a few other arenas as well but it is and will always remain primarily a contest prep bodybuilding tool. As you may have guessed, for it is very common in the performance enhancing world, Lasix was not designed with bodybuilding or any athletic endeavor in mind and very few performance enhancing medications are but as is common a welcomed home and purpose is found and sometimes this purpose ends up being the particular medications greatest one. No, Lasix does not fit this bill, for its role outside the world of performance enhancing is far more beneficial but it is a tool that can be used effectively nevertheless.


Comprised of the active drug Furosemide and commonly known by its most popular trade name “Lasix” Furosemide is a loop diuretic that was created to treat issues of edema; most notably Lasix is used in the treatment of congestive heart failure, a condition that is accompanied by severe to even extreme edema. The purpose of this medication is simple, the removal of fluid from the body and in Lasix we have a very powerful form. No, Lasix is not a hormone, it is simply a diuretic.

Lasix can be found in both injectable and oral tablet form with the tablets being far more common and the injectable far more powerful. Injectable Lasix will begin working through the body a mere few short minutes after administration while tablets will take approximately one hour before any action is seen, perhaps even a little longer in some individuals.

As a Lasix makes it presence known it begins to change how the body responds to both fluid and sodium and as we will see it does so dramatically. Normally (without Lasix) sodium and water are filtered from the blood where they then enter the tubules of the kidney and in the end this filtered fluid becomes urine. A large portion of the filtered sodium and water is initially reabsorbed into the blood; it is only the byproduct waste that is passed as urine. Now enter Furosemide which when present actively prohibits absorption of sodium and water thereby increasing the amount of urine passed; what doesn’t absorb must go somewhere and the only place it can go is out. As you may have guessed this is one powerful diuretic and the effects can be harsh and long lasting when compared to other popular diuretics. The effects of an oral tablet will last approximately 8 hours with injectable forms of Lasix lasting approximately 2 hours.

The Benefits of Lasix:

The benefits of Lasix are simple and in truth there really isn’t a lot to say; after all the purpose, the entire purpose is to remove fluid and that’s all. However, the purpose for this purpose can vary and it is in that we may find the benefits of use. For the competitive bodybuilder it is very simple; it is not enough to be lean, he must also be dry and hard and as hard as he can possibly be. You may have heard the term “Thin Skin” in reference to bodybuilding before and a lot of this has to do with leanness but the amount of water one carries also plays a role. In the final week of a contest prep plan the bodybuilder will begin greatly manipulating his diet in order to finally truly manipulate his water right before the end and diuretics such as Lasix often play a key role; after all, they push the water out and can provide (if you’re lean enough) a harder and more granite like look.

This is not the only arena of performance enhancing Lasix use; in any sport where weight is an issue they can be found there as well but it is strongly cautioned against as we will see. If an athlete is above his desired weight and needs to drop weight fast to make a certain weight class some athletes will supplement with Lasix to push fluid out just like a bodybuilder would and as the fluid leaves the body their weight necessarily decreases.

The Side-Effects of Lasix:

While the removal of water is the very idea this does not come without cost and the side-effects of this loop diuretic are also part of its intended effect; in that we have somewhat of a unique situation. As you recall, Lasix not only push water out but sodium too but they also remove potassium. The removal of water is a very delicate process when it’s not being done out of necessity; necessity means you need it medically and that does not include performance enhancement. However, when we add the removal of sodium and potassium to the equation what was tricky just got a little more so; yes, the absence of sodium may give you a dryer harder look but with sodium and potassium being absent you risk severe electrolyte imbalance. It is very easy to begin cramping up when this medication is present; no, we don’t mean a little stinger up the back of your leg, we’re talking about some of the worst cramps you’ve ever felt; the stories of bodybuilders with full body cramps, there’s a lot of myths and legends about bodybuilding but this is not one of them. Because Lasix can be so harsh, while powerfully effective many in the bodybuilding world have begun to opt for potassium sparing diuretics; most popular is the Triamterene and Hydrochlorothiazide combo commonly sold under the trade name Dyazide.

Should You Supplement with Lasix?

There’s no doubt about it, the advantage of Lasix use is very high as this diuretic is very strong; however, as it is so strong it comes with a price and some no matter how well intended will simply not be able to physically handle it. We cannot recommend Lasix for most athletes, for most of you it’s just too risky; after all, if you’re cramping up so badly you can’t move then does it really matter how good you look or how well you can perform? However, under the right guidance it can be very useful and in elite bodybuilding this is a place where it probably has a long standing future but elite bodybuilding is something most will never be a part of and in those cases potassium sparing diuretics will always be your best choice.

Lasix Cycles & Doses:

Unlike many of the hormones an medications we discuss you do not cycle Lasix like you would anabolic steroids, peptide hormones, SERM’s or many of the other items discussed; these are short used items, very short and while it may sound simplistic your best bet if you use it is to use very little as it will go a long way. For most a dosing of 20mg 3 times the day before competition is a good place to start, followed by another 20mg the following morning, say before a bodybuilding prejudging. Yes, more may be needed but you really need to start low. If you feel 20mg dosing is not enough try adding 50mg of Aldactone to each Lasix dosing before you increase the actual Lasix dose.

We must remember, this is a diuretic and that means it can not only dehydrate you but as it is one of the most powerful ones it can do so severely and it is absolutely impossible to know how strongly it will react in you. Further, it is imperative you take a good potassium supplement with your Lasix; remember, Lasix not only drains water but potassium to. Failure to use with caution will make Lasix one of the most dangerous medications any performance enhancer could ever use as dehydration can become so intense it cost one his life. If you experience dizziness, cramping or vomiting you need to take care of yourself, rehydrate, supply your body with the electrolytes needed immediately and forget about the little competition you have planned; failure to ignore this warning could very well result in death and if you’re dead what good is your contest?


Understanding Lasix

Lasix come in two forms, tablets and injectable solutions but most who use will find tablet form is all they need. Regardless of the form you choose the drugs action is the same except for the initial activity time. Oral Lasix tablets will take approximately one hour to become active in the body while injectable versions will begin working within minutes. Once action begins, regardless of the form, it will continue to perform for approximately 3-4 hours.

The mode of action is simple; once Lasix is present it flushes water out of the body at a rapid rate; yes, you will need to have a bathroom on hand while using the medication; however, as awesome as this sounds there is a downside. Along with flushing water out of your body Lasix will flush potassium and sodium out as well at an equally high rate. If you understand anything about nutrition and simple human function you understand how problematic this can be. Lasix can cause a serious imbalance in electrolytes and bring about a host of unwanted side-effects due to this fact.

If we decide to use Lasix we will necessarily supplement with a good potassium chloride; this is a must but we will further only take the bottles recommended amount as too much will lead to possible cardiac arrest Further, because Lasix drain the body so rapidly many competitors are left looking flat, even with a massive carb-up they still look flat. More often than not this is due to too much Lasix being taken, water being cut way too early; as well as not understanding proper carb-up protocol but that’s another story.

While the desired effect can be obtained through Lasix use, because of its severity many competitive bodybuilders have increasingly begun using other diuretics, particularly potassium sparing diuretics such as Dyazide. While diuretics such as Dyazide are not as powerful or as fast acting, with proper final week protocol the same end result can be achieved; a dry and hard physique.