The human body naturally produces approximately 30mcg of T3 endogenously per day.
Therefore, many users who intend to use Cytomel ‘safely’ by starting at 25mcg per day are actually moving backward rather than forward.
A daily T3 dosage of 25mcg is actually less than what the body normally produces.
The attempt to use a very low initial dose of T3 to use it ‘safely’ is actually the result of fear, propagated by individuals within the performance-enhancing drug community, that T3 is an extremely dangerous drug, even though it is not more dangerous than most other hormonal drugs like anabolic steroids.
Another concept that needs to be addressed in this profile is the practice of slowly titrating up (ramping up) the T3 dose, which has become an unnecessary practice in most cases.
The claim raised in the performance-enhancing drug community regarding Cytomel dose increases is that the thyroid is a very sensitive organ and that increasing the Cytomel dose too quickly or too high can cause it to shut down permanently.
This claim is, once again, incorrect and not supported by clinical evidence.
One of the misconceptions that has persisted regarding T3 for the past two decades is that the thyroid will be permanently damaged.
The truth and reality are that the thyroid gland functions just like the other endocrine glands in the human body.
In fact, the thyroid has been found to be one of the slowest-reacting endocrine glands to negative feedback loops.
In several specific clinical studies, patients who had been administered T3 for years recovered their endogenous thyroid hormone production within weeks; in fact, some of these patients, who were taken off the drug after being misdiagnosed, were found to have been administered T3 for 30 years [1] [2].
All subjects involved in the aforementioned clinical studies recovered their thyroid function within a very short period.
Looking specifically at the study findings:
The pattern of thyrotropin secretion was analyzed by sequential measurements of thyroidal 131l uptake, serum thyroxine, triiodothyronine, and thyrotropin concentrations and the response to thyrotropin-releasing hormone before and after withdrawal of long-term thyroid hormone administration in seven hypothyroid women.
During exogenous hormone administration, 131l uptake was suppressed, and serum thyrotropin concentrations, both before and after thyrotropin-releasing hormone administration, were undetectable.
After exogenous hormone was discontinued, thyrotropin secretory capacity was transiently impaired, as indicated by undetectable basal thyrotropin concentrations and the absence of a response to thyrotropin-releasing hormone, whereas basal thyrotropin concentrations were normal and the response to releasing hormone was normal during the period when serum thyroxine and triiodothyronine concentrations were subnormal.
The reduction in thyrotropin reserve persisted for two to five weeks, and the appearance of detectable serum thyrotropin (less than 1.2 μU per milliliter) and normal 131l uptake usually occurred simultaneously within two to three weeks.
Serum thyroxine concentrations do not return to normal until at least four weeks after hormone withdrawal.1
Therefore, the claim in the exercise and bodybuilding community that T3 can or will cause permanent thyroid damage should not be believed at all.
This is merely speculation and rumor that has been raised over the past two decades.
Medical T3 Dosage
The typical medical Cytomel dosage for the treatment of hypothyroidism is a starting dose of 25mcg per day.
The patient is then assessed for their response and tolerance to the drug, and the Cytomel dose is adjusted by no more than 25mcg per day.
The average maintenance T3 dose is 25–75mcg per day.
Once the patient reaches their desired optimal dose, this dose is administered steadily for the remainder of the treatment period.
T3 Dosage for Body Fat Reduction
Bodybuilders and athletes wishing to use T3 for weight loss and fat reduction effects generally start with a T3 dose of 25–50mcg per day to assess tolerance.
Tolerance is related to the experience of the metabolic and fat-burning effects, as well as the associated increase in body temperature.
It must be understood that individuals respond differently and with different intensities to a given Cytomel dose, meaning that a 50mcg T3 dose may induce steady fat loss in one individual, while the same 50mcg dose may have little effect on another.
After maintaining the 50mcg dose for a day or two and assessing tolerance, the Cytomel dose should be increased by an additional 25mcg each day (or every other day, depending on the individual’s experience) until the maximum optimal dose is reached.
The common maximum dosage for most male bodybuilders and athletes is in the range of 75–100mcg per day.
Some individuals may use up to 125mcg per day, but this is a very high figure and is generally not recommended.
Female T3 Dosage
In most cases, the female response to the effects of Cytomel (T3) is exactly the same as the male response.
The only major difference in the female Cytomel dosage is the difference in weight and mass.
Since women tend to be smaller in overall size, weight, and body mass than men, they may be more sensitive to a given T3 dose.
The recommended maximum effective dose for most women is approximately 50–75mcg per day, with 75mcg being the highest dose.
Proper T3 Dosing Amount and Timing
T3 has a half-life of 2.5 days, so it is sufficient to consume the entire daily Cytomel dose in the morning; there is no need at all to split the T3 dose throughout the day.
Furthermore, there is also no need at all to ramp up (slowly increase) the Cytomel dosage.
It is only advisable for an individual to do so initially when they are first using T3, in order to get a feel for the compound’s effects and to gauge the increase in body heat production and the potential for muscle loss.
Once an individual knows their maximum effective optimal dose, there is generally no need to slowly increase the T3 dose, and they can start at their known optimal Cytomel dose without issue.
By the same token, there is also no need to slowly ramp down the T3 dose at the end of a T3 cycle.
There was a common belief that abruptly stopping could cause permanent damage to the thyroid.
However, according to the previously mentioned study findings, this is not true.
In fact, the best course of action is to remove all T3 doses immediately upon cessation of use, so that the thyroid hormone can resume function as quickly as possible.
While exogenous thyroid hormone is being administered, the thyroid hormone cannot recover due to the negative feedback loop.
This remains true even if the Cytomel dose is gradually reduced.
Therefore, just as with anabolic steroids, it is best to stop administration immediately so that function can resume as quickly as possible.
Expectations and Results from T3 Use
T3 is a compound that powerfully stimulates the body’s metabolism at the cellular level, and it does not distinguish between the various substrates (protein, carbohydrates, fat) it uses for energy.
Therefore, it is important to understand that while fat loss can sometimes be dramatic, muscle loss can occur if T3 is used without anabolic steroids, particularly beyond certain dosages (approximately above 50mcg of T3).
The greater the dosage of T3, the greater and faster the potential muscle loss can be.
It is also important for the reader to know and understand that excessive amounts of anabolic steroids are absolutely not necessary for muscle preservation during T3 use.
Using a total of 300-500mg of anabolic steroids (all anabolic steroids combined) per week should be sufficient to preserve muscle and maintain nitrogen balance while using higher doses of T3.
More potent anabolic steroids like Trenbolone or Winstrol can prevent muscle loss from T3 at doses as low as 200mg per week.
Using excessive amounts of anabolic steroids for the purpose of muscle preservation during T3 use is entirely unnecessary.
T3 Side Effects
Cytomel (T3) is generally well-tolerated by most users, and side effects are mostly related to hormone overdose.
The most noticeable (and desired) T3 side effect is the increase in body heat output due to Cytomel’s ability to increase whole-body metabolism.
The increased metabolic rate through energy production and consumption in the body generally results in a greater amount of heat output, which can be monitored using a personal thermometer.
The reason athletes and bodybuilders desire this specific Cytomel side effect is because this compound plays a very powerful role in actually increasing the metabolic rate.
If overall body temperature does not increase at all after T3 use, it is a strong signal that the product is fake, the dosage is too low, or there is an issue at the cellular level regarding T3’s proper function (refer to the details in the Cytomel (T3) Cycle section of this profile for information on using Cortisol and L-Carnitine with T3).
The method for measuring body temperature during T3 use involves the athlete or bodybuilder monitoring their body temperature for several days before starting T3 use.
This includes measuring body temperature immediately upon waking in the morning and again during the day while at rest (not near times of strenuous physical activity).
After monitoring for several days, an average is calculated.
When starting T3 use, body temperature is measured again in the same manner starting from the first day of use (measure body temperature immediately upon waking, and then again once during the day).
The increase in body temperature due to Cytomel’s (T3) metabolism-boosting effect should not be dramatic, but rather an increase of about 1-2 degrees above the normal average body temperature recorded when the user was not administering T3.
An increase in body temperature to the point of feeling uncomfortably hot, or an increase of more than 1 degree, indicates a serious problem (thyroid storm) and immediate medical assistance should be sought.
Aside from increased body temperature, common Cytomel side effects can include increased heart rate and/or irregular heartbeat.
It is important to understand that T3 is not a stimulant and does not exhibit stimulant-like effects on the body.
Tremors, shaky hands, anxiety, or other stimulant-like side effects are not associated with T3 use.
However, some individuals report an increased heart rate and, particularly at high doses, a pounding heart while using T3.
This is because T3 is an essential mediator in heart rate regulation, not due to a stimulant effect.
Generally, these T3 side effects on heart rate and heart beat are associated with very high T3 dosages.
Other, less frequently occurring Cytomel side effects (often associated with overdose) include headache, irritability, sweating, nervousness, irregular heartbeat, menstrual irregularities, and increased bowel movements.
Acute T3 overdose can be life-threatening.
T3 References
[1] Recovery of pituitary thyrotropic function after withdrawal of prolonged thyroid-suppression therapy. N Engl J Med 1975 Oct 2;293(14):681-4 Vagenakis AG, Braverman LE, Azizi F, Portinay GI, Ingbar SH.
[2] The pattern of recovery of the hypothalamic-pituitary-thyroid axis in patients taken off chronic thyroid therapy. 1975 Jul;41(1):70-80 Krugman LG, Hershman JM, Chopra IJ, Levin GA, Pekary E, Geffner DL, Chua Teco GN.
