Until recently, Cytomel was used by bodybuilders and female bodybuilders, in particular-on a daily basis over several months to remain "hard" and in good shape all year round. Believe us when we tell you that to a great extent several bodybuilders who are pictured in "muscle magazines" and display a hard and de­fined look in photos, eat fast food and iron this out by taking Cytomel. The over stimulated thyroid burns calories like a blast furnace. Nowadays, instead of Cytomel, athletes use Clenbuterol which is becoming more and more popular. Those who combine these two compounds will burn an enormous amount of fat. The next time you read that a certain pro bodybuilder approach­ing a championship competition is still eating 4000 calories a day, you will know why. Cytomel is also popular among female bodybuilders. Since women generally have slower metabolisms than men, it is extremely difficult for them to obtain the right form for a competition given today's standards. A drastic reduc­tion of food and calories below the 1000 calorie/day mark can often be avoided by taking Cytomel. Women, no doubt, are more prone to side effects than men but usually get along well with 50 mcg/day. A short-term intake of Cytomel in a reasonable dosage is certainly "healthier" than an extreme hunger diet.

As for the dosage, one should be very careful since Cytomel is a very strong and highly effective thyroid hormone. It is extremely impor­tant that one begins with a low dosage, increasing it slowly and evenly over the course of several days. Most athletes begin by tak­ing one 25 mcg tablet per day and increasing this dosage every three to four days by one additional tablet. A dose higher than 100 mcg/ day is not necessary and not advisable. It is not recommended that the daily dose be taken all at once but broken down into three smaller individual doses so that they become more effective. It is also impor­tant that Cytomel not be taken for more than six weeks. At least two months of abstinence from the drug needs to follow. Those who take high dosages of Cytomel over a long period of time are at risk of developing a chronic thyroid insufficiency. As a consequence, the athlete might be forced to take thyroid medication for the rest of his life. It is also important that the dosage is reduced slowly and evenly by taking fewer tablets and not be ended abruptly. Those who plan to take Cytomel should first consult a physician in order to be sure that no thyroid hyper function exists.

Possible side effects such as medication are described in the package insert by the German pharmaceutical group Hoechst AG for their compound Thybon: "Exceeding the individual limits of compatibil­ity for liothyronine or taking an overdose, especially, if the dose is increased too quickly at the beginning of the treatment, can cause the following clinical symptoms for a thyroid hyperfunction): heart palpitation, trembling, irregular heartbeat, heart oppression, agita­tion, shortness of breath, excretion of sugar through the urine, ex­cessive perspiration, diarrhea, weight loss, psychic disorders, etc., as well as symptoms of hypersensitivity." Our experience is that most symptoms consist of trembling of hands, nausea, headaches, high perspiration, and increased heartbeat. These negative side effects can often be eliminated by temporarily reducing the daily dosage. Cau­tion, however is advised when taking Cytomel since, especially in the beginning, the effect can be quick and sometimes drastic. Ath­letes do not use the injectable version of L-T3, this is normally used as "emergency therapy for thyrotoxic coma." Those who use Cytomel over several weeks will experience a decrease in muscle mass. This can be avoided or delayed by simultaneously taking steroids. For the most part, since Cytomel also metabolizes protein, the athlete must eat a diet rich in protein.

Cytomel is a synthetic T3 hormone. As you may already know, most natural T3 is not produced directly by your thyroid gland, but rather is converted from the T4 thyroid hormone. (8)

Natural T3 is a regulator of the oxidative metabolism of energy producing substrates (food or stored substrates like fat, muscle, and glycogen) by the mitochondria. The mitochondria, as you will recall from your high school biology class, are usually referred to as the "cell´s powerhouses" because they produce ATP. Taking Cytomel (supplemental T3) greatly increases the uptake of nutrients into the mitochondria and also their oxidation rate (i.e. the rate at which they are burned for energy), by increasing the activities of the enzymes involved in the oxidative metabolic pathway. Everything is working harder, in other words, and more fuel is needed to supplement this increased work rate. Therefore, as you can guess, taking supplemental Cytomel will increase your body´s energy demands. And if you are in a hypocaloric state, you will begin burning even fatter primarily due to an increase in ATP. This increased ATP causes an increase in overall metabolic activity. (8)(9)This is exactly what we want, and is why we would be taking thyroid hormones like Cytomel in the first place. If you aren´t taking anabolic steroids with your Cytomel, however, your body may start to eat away muscle to provide energy for you to function. Remember mitochondria/ATP aren´t very picky, but they are very efficient. What I mean by this is that they will use whatever is on hand to generate energy for your body to continue functioning, fat, protein, glucose; it doesn´t matter to ATP, as long as there´s something to give them energy. Taking this drug will increase their need to find something to burn to create this energy. Ergo, if we aren´t taking anabolic steroids while taking our T3, we may lose too much muscle, especially while dieting.
Thus we can see that there are many advantages to using Cytomel to optimize our metabolic rate. It will also increase your body´s ability to synthesize protein, but from what I´ve seen personally, it acts as a catabolic when it isn´t administered with anabolic steroids. It is often the last thing added into a precontest diet, as it has a reputation for getting rid of the last few percentages of bodyfat& the "sticky fat" as it´s called in bodybuilding, the fat that just doesn´t want to leave you in the last few weeks of dieting. I think this is a poor use for this drug, and that it should be the first thing added into a diet to lose fat, as it will optimize your metabolic rate, which should be done at the outset of a diet, not after the calorie restriction has diminished your thyroid output and you are adding it in simply to replace what was lost.

Unfortunately, in all of the studies I´ve seen, T3 also increased growth hormone production. (5)(6) As we all know, GH is also a strongly lipolytic compound, and this is another mechanism by which T3 may exert its effects, although I suspect this would only be a small percentage of its overall effects. This being the case, it has always been somewhat problematic to me to note that when GH and T3 are used together, the increased nitrogen retention normally found with GH use is negated. (7). If you were only using T3 and GH this may be a problem, but as I´ve already stated, you are going to need some anabolic agents if you are using T3. And as you have read previously, I recommend the veritable anabolic/lipolytic orgy of Insulin, T3, Anabolic Steroids, GH, and insulin, for 100% maximum results in minimal time.
On the brighter side, and of special note to dieters, administration of T3 has been shown to upregulate the beta 2 receptors in fat tissue. As you know clenbuterol and similar compounds downregulate this receptor, so using T3 with your clen will help stave off or reverse this downregulation. (1)(2)(3)(4). I would still recommend taking your benadryl every third week, though.

Finally, I would like to address the issue of recovery of your natural thyroid function after you stop taking cytomel. The horror stories of people on permanent thyroid replacement just aren´t true. I remember a few years ago, the rumor was circulating that the current Ms.Fitness had permanently shut off her thyroid gland, and was now fat and on thyroid hormone permanently. This is just another horror story based in nothing but conjecture and rumor, the studies I´ve looked at have shown people recovering their thyroid hormone relatively quickly (within months, at most) after going off of several YEARS (!) of thyroid replacement therapy (10)(11). I speculate that you can optimize your metabolic rate with Cytomel for 9-10 months a year, and just normalize yourself for 2-3 months (perhaps the winter, when you are mostly covered up), and then go right back on. Some people in the studies I read were on T3 for 30 years and recovered their natural thyroid function within short order. I think we can safely spend an athletic career using Cytomel 9-10 months out of the year, and just taking those few months off to normalize ourselves. Is this aggressive? Yes. Is this unsafe? NO.

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11. Patterns off recovery of the hypothalamic-pituitary-thyroid axis in patients taken of chronic thyroid therapy. J Clin Endocrinol Metab 1975 Jul;41(1):70-80 Krugman LG, Hershman JM, Chopra IJ, Levine GA, Pekary E, Geffner DL, Chua Teco GN