Cytomel — liothyronine sodium

Liothyronine sodium is a synthetically manufactured prescription thyroid hormone. It specially consists of the L-isomer of the natural thyroid hormone triiodothyronine (T3). Thyroid hormones stimulate basal metabolic rate, and are involved with many cellular functions including protein, fat, and carbohydrate metabolism. Liothyronine sodium is used medically to treat hypothyroidism, a condition where the thyroid gland does not produce sufficient levels of thyroid hormone. Hypothyroidism is usually diagnosed with a serum hormone profile (T3, T4, & TSH), and may manifest itself with symptoms including loss of energy, lethargy, weight gain, hair loss, and changes in skin texture. T3 is the most active thyroid hormone in the body, and consequently liothyronine sodium is considered to be a more potent thyroid medication than levothyroxine sodium (T4).

Bodybuilders and athletes are attracted to liothyronine sodium for its ability to increase metabolism and support the breakdown of body fat. Most often utilized during contest preparation or periods of “cutting”, the drug is usually said to significantly aid in the loss of fat, often on higher levels of caloric intake than would normally be permissive of such fat loss. To this end, the drug is also commonly used in conjunction with other fat loss agents such as human growth hormone or beta agonists. Some users also ascribe an ability of thyroid hormones like liothyronine sodium to increase the anabolic effect of steroids. While in theory these drugs may support the greater utilization of protein and carbohydrates for muscle growth, they are not widely proven or accepted for this purpose.

Brand name Cytomel, Liothyronine sodium

Liothyronine Sodium History

The first medication that included T3 was technically a thyroid extract, first given to a patient with myxedema (a skin disorder associated with hypothyroidism) in 1891. Natural thyroid extracts contained therapeutically viable levels of the thyroid hormones T3 and T4, and were widely used in medical practice for more than 60 years. In the 1950s, however, these drugs slowly start giving way to new synthetic thyroid medications, namely liothyronine sodium and levothyroxine sodium, which were consistent in dosage and effect, and more desirable to consumers than prepared animal extracts. Although liothyronine sodium and levothyroxine sodium are both widely available in the U.S. and abroad to this day, liothyronine retains a significantly smaller portion of the global thyroid market. Given its more potent and fast acting effect, however, liothyronine sodium remains a popular thyroid drug with bodybuilders and athletes. Cytomel is the most recognized trade name for the drug in the U.S, where it is presently sold under the King Pharmaceuticals brand name.

How is Liothyronine Sodium Supplied

Liothyronine sodium is most commonly supplied in oral tablets of 5 mcg, 25 mcg, and 50 mcg.

Structural Characteristics of Liothyronine Sodium

Liothyronine sodium is a synthetic form of T3 thyroid hormone. It has the chemical designation l-tyrosine,o-(4- hydroxy-3-iodophenyl)-3,5-diiodo-,monosodium salt.

Liothyronine Sodium Warnings

FDA requires the following black box warning accompany prescription liothyronine sodium products sold in the U.S.: “Drugs with thyroid hormone activity, alone or together with other therapeutic agents, have been used for the treatment of obesity. In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction. Larger doses may produce serious or even life-threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines such as those used for their anorectic effects.”

Liothyronine Sodium Side Effects

Side effects are generally associated with overdosage, and may include headache, irritability, nervousness, sweating, irregular heartbeat, increased bowel motility, or menstrual irregularities. Overdosage may also induce shock, and may aggravate or trigger angina or congestive heart failure. Chronic overexposure to liothyronine sodium will produce symptoms normally associated with hyperthyroidism or the overproduction of natural thyroid hormones in the body.The occurrence of overexposure-linked side effects is normally cause to immediately reduce or discontinue therapy with liothyronine sodium. Acute massive overdose may be life threatening.

Liothyronine Sodium Administration

When used to treat mild hypothyroidism, the typical recommended starting dosage is 25 mcg daily. The daily dosage then may be increased by no more than 25 mcg every 1 to 2 weeks. The established maintenance dose is usually 25-75 mcg per day. Once a day administration of the full daily dose is usually recommended. Although liothyronine sodium is fast acting, its effects may persist in the body for several days after discontinuance.

The usual protocol among bodybuilders and athletes taking liothyronine sodium to accelerate fat loss involves initiating its use with a dosage of 25 mcg per day. This dosage may be increased by 25 mcg every 4 to 7 days, usually reaching a maximum of no more than 75 mcg per day. As in a medical setting, the intent of this slow buildup is to help the body become adjust to the increasing thyroid hormone levels, and avoid sudden changes that may initiate side effects.

Cycles of liothyronine sodium usually last no longer than 6 weeks, and administration of the drug should not be halted abruptly. Instead, it is discontinued in the same slow manner in which it was initiated. This usually entails reducing the dosage by 25 mcg every 4 to 7 days. This tapering is done so that the body has time to readjust its endogenous hormone production at the conclusion of therapy, and to avoid the onset of side effects.

Liothyronine Sodium Availability

Liothyronine is an old and widely prescribed medication. It can be found readily in most areas of the world, and is sold in a variety of different brand and generic forms. Counterfeiting is not a large-scale problem. It is important to note than one should never purchase an injectable form of this drug. These are generally used

Bodybuilders reference

Cytomel is the synthetic form of T-3/L-triiodothyronine and was a commonly known trade or brand name among athletes. T-3/L-triiodothyronine is used as a form of thyroid hormone therapy mostly in Europe. Most bodybuilders favored this drug over synthetic forms of T-4/L-thyroxine due to its vastly superior activity level.

An advantage of T-3/L-triiodothyronine administration over T-4/L-thyroxine was the lack of dependence upon the liver enzyme responsible for T-4/T-3 conversion. During diet restricted periods the liver naturally decreases the liver enzyme levels as a control measure to prevent metabolic rate induced starvation. Just as the liver increases production of this enzyme in response to elevated calorie intake it also reduces levels in response to decreased calorie intake. Remember that T-4 /L-thyroxine is only 20% as active as T-3/L-triiodothyronine.

The abuse of synthetic T-3/L-triiodothyronine will result in severe suppression of natural (endogenous) thyroid function. This is especially true of this drug because it actually circumvents the normal thyroid hormone manufacturing process the body utilizes to produce endogenous forms as required. Simplified this is because T-3/Ltriiodothyronine is the most potent thyroid hormone so the body shuts down each level required for production to try to reduce circulatory T-3/L-triiodothyronine levels. Of course this does not reduce the level if the hormone is being administered exogenously (from outside the body).

Since long term use of T-3 /L-triiodothyronine will lead to thyroid function suppression the issue of rebound should be briefly discussed. It is commonly stated that synthetic thyroid hormone abuse will lead to permanent thyroid gland dysfunction. Though it is definitely a physiological possibility, I have not yet found a case study to support this statement. However, there is a common occurrence of thyroid gland/function rebound in natural endogenous thyroid hormone production. It seems that it was common for individuals to realize an "increase" in endogenous thyroid hormone production of 120-130 % within 3-15 days after drug discontinuance. This means an individual would commonly see an increase in their thyroid hormone production of 20- 30% above their normal pre-drug administration levels, in many cases.

Anabolic Steroid Guide reference

Cytomel
Cytomel is not an anabolic/androgenic steroid but a thyroid hormone. As a substance it contains synthetically manufactured liothyronine sodium which resembles the natural thyroid hormone tricodidethyronine (L-T3). The thyroid of a healthy person usually produces two hormones, the better known Lthyroxine (L-T4) and the aforementioned L-triiodine-thyronine (L-T3). Since Cytomel is the synthetic equivalent of the latter hormone, it causes the same processes in the body as if the thyroid were to produce more of the hormone. It is interesting to note that L-T3 is clearly the stronger and more effective of these two hormones. This makes Cytomel more effective than the commercially available LT4 compounds such as L-thyroxine or Synthroid. L-T3 has proven to be 4-5 times more biologically active and to take effect more quickly than L-thyroxine (L-T4)." In school medicine Cytomel is used to treat thyroid insufficiency (hypothyroidism). Among other secondary symptoms are obesity, metabolic disorders, and fatigue. Bodybuilders take advantage of these characteristics and stimulate their metabolism by taking Cytomel, which causes a faster conversion of carbohydrates, proteins, and fats. Bodybuilders, of course, are especially interested in an increased lipolysis, which means increased fat burning. Competing bodybuilders, in particular, use Cytomel during the weeks before a championship since it helps to maintain an extremely low fat content, without necessitating a hunger diet. Athletes who use low dosages of Cytomel report that by the simultaneous intake of steroids, the steroids become mote effective, most likely as the result of the faster conversion of protein.

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. 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 caloric/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 hyperfunction exists.

Possible side effects are: 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. 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. L-T3 can usually be found quite easily. 100 tablets of 0.05 mg each cost approx. $40. It is unlikely that there will be fakes.

L-thyroxine T-4
L-Thyroxine is a synthetically manufactured thyroid hormone. Its effect is similar to that of natural Lthyroxin (L-T4) in the thyroid gland. L-thyroxin is one of two hormones which is produced in the thyroid. The other one is L-triiodthyronine (L-T3, see Cytomel). L-thyroxin is clearly the weaker of the two hormones. For this reason it is often used for a longer time period than L-T3. Bodybuilders use LThyroxine to accelerate the metabolizing of carbohydrates, proteins, and fat. The body burns more calories than usual so that a lower fat content can be achieved or the athlete burns fat although he takes in more calories. In the past L-Thyroxine was often used by competing bodybuilders. Unfortunately, with increased dosages (more than 400 to 600 mcg/day) usually not only more fat but more carbohydrates and proteins are burned as well. The athlete no doubt becomes harder but he can also lose muscle mass if steroids are not administered simultaneously. L-Thyroxine is rarely used today since most athletes use Cytomel or Triacana. When used properly there are few side effects to L-Thyroxine. Dosages that are too high and, in particular, dosages that are increased too quickly and too early at the beginning of intake can cause trembling of the fingers, excessive perspiration, diarrhea, insomnia, nausea, increased heartbeat, inner unrest, and weight loss.

The dosages taken by athletes are usually in the range of 200-400 mcg/day. We advise that you begin with a small dose and increase it slowly and evenly over several days. L-Thyroxine is a prescription drug and available only in pharmacies. One hundred tablets of 150 mcg each of the compound Levothroid cost about $50 on the black market. Unlike Cytomel and Triacana, L-Thyroxine is rarely found on the black market.

Newbies Research Guide reference

Cytomel is not an anabolic/androgenic steroid but a thyroid hormone. As a substance it contains synthetically manufactured liothyronine sodium which resembles the natural thyroid hormone Tricodide-thyronine (L-T3). The thyroid of a healthy person usually produces two hormones, the better known L-thyroxine (L-T4) and the aforementioned L-trilodine~thyronine (L-T3). Since Cytomel is the synthetic equivalent of the latter hormone, it causes the same processes in the body as if the thyroid were to produce more of the hormone. It is interesting to note that L-T3 is clearly the stronger and more effective of these two hormones. This makes Cytomel more effective than the commercially available L-T4 compounds such as L-thyroxine or Synthroid. The manufacturer of the German L-T3 com- pound, Hoechst AG, ascribes the following characteristics to its Thybon drug, making it clear that L-T3 is superior to L-T4: “The synthetically manufactured thyroid hormone, L-trilodine-thyronine (L-T3), included in Thybon, in experimental and clinical testing has proven to be 4-5 times more biologically active and to take effect more quickly than L-thyroxine (L-T4).” In school medicine Cytomel is used to treat thyroid insufficiency (hypothyroidism). Among other secondary symptoms are obesity, metabolic disorders, and fatigue. Bodybuilders take advantage of these characteristics and stimulate their metabolism by taking Cytomel, which causes a faster conversion of carbohydrates, proteins, and fats. Bodybuilders, of course, are especially interested in an increased lipolysis, which means increased fat burning. Competing bodybuilders, in particular, use Cytomel during the weeks before a championship since it helps to maintain an extremely low fat content, without necessitating a hunger diet. Athletes who use low dosages of Cytomel report that by the simultaneous intake of steroids, the steroids become more effective, most likely as the result of the faster conversion of protein.

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 hypersen- sitivity.” 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 thyrotox- ic 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.

References

Wlliam Llewellyn (2011) - Anabolics
L. Rea (2002) - Chemical Muscle Enhancement Bodybuilders Desk Reference
Anabolic Steroid Guide
Newbies Research Guide

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