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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 hyperfunction exists.
Possible side effects are: heart palpitation, trembling, irregular heartbeat, heart oppression, agita-tion, 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. 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.