British Dragon Cytomel Tablets 100 tabs (50 mcg/tab)

Liothyronine – Cytomel

Thyroid hormones are produced naturally in the body, yet many pharmaceutical companies offer synthetic forms. The two primary types are T4 (levothyroxine) and T3 (liothyronine), both synthesized and stored in the thyroid gland.

Thyroid hormone preparations from manufacturers are derived either from animal sources (bovine or ovine) or produced synthetically. In the USA, the iodine content is strictly regulated.

Cytomel (liothyronine sodium) is offered as both tablets and as a naturally occurring thyroid hormone salt. Notably, T3 is significantly more potent than T4.

Pharmacology

Although the precise mechanisms of thyroid hormones remain elusive, they instigate numerous biochemical processes within cells, primarily boosting energy levels by increasing carbohydrate, lipid, and protein metabolism while enhancing oxygen consumption. Patients on thyroid hormones typically exhibit a higher basal metabolic rate, affecting nearly every organ in the body, particularly the brain. The significance of thyroid hormones is starkly visible in those suffering from deficiencies.

Dosage

Thyroid hormones are quickly absorbed through the stomach into the bloodstream, with a rapid onset of action usually occurring within a few hours. However, peak activity may take several days. Thyroid hormones can remain in the body for days after administration, binding to albumin in the blood to prevent rapid degradation by the liver.

Indications for thyroid hormone include:

• Replacement therapy for hypothyroidism
• Post-surgical thyroid removal therapy
• Management of goiters and thyroid nodules
• Diagnostic use in thyroid suppression tests
• Alternative for patients allergic to pork or beef thyroid preparations

Body Builders and Weight Loss

Athletes, both amateur and professional, have misused thyroid hormones like Cytomel for weight loss and improved athletic performance due to their ability to burn fat and carbs. Typically, it is taken for 4-6 weeks, ceasing one week before competition. Cytomel is recognized for its efficacy as a fat burner and energy enhancer. However, athletes often take various supplements, complicating the results.

Marketing claims suggest starting Cytomel at 25 mcg/day, gradually increasing the dose by 5-10 mcg/day, with a maximum daily dosage around 100 mcg considered safe. Reportedly, weight loss may take 6-12 weeks, but caution is advised due to potential thyroid insufficiency upon cessation of the drug, necessitating a gradual dosage taper to restore thyroid function.

Consultation with a physician is strongly recommended for those considering off-label use of thyroid hormones for weight loss.

Signs and Symptoms

Excessive thyroid hormone can lead to an array of side effects:

• Headaches
• Mood swings, including irritability and anxiety
• Increased sweating
• Irregular heart rhythms
• Palpitations
• Chest pain
• Diarrhea
• Menstrual irregularities
• Exacerbation of heart failure
• Shock

Severe overdose may mimic thyroid storm, while chronic excessive use results in hyperthyroidism symptoms.

Contraindications

Thyroid hormones should generally be avoided by individuals with untreated adrenal cortical insufficiency, thyrotoxicosis, or any hypersensitivity to active or inactive ingredients. True allergic reactions to liothyronine are reportedly rare.

Weight Loss Misconceptions

While some use thyroid hormones for weight loss, typical doses are insufficient. Higher doses come with risks, potentially dangerous when combined with substances like ephedrine or growth hormone.

Specific conditions including adrenal insufficiency and diabetes may warrant careful thyroid hormone management, as they can influence anticoagulant sensitivity and bleeding risks. Claims of efficacy in treating infertility with thyroid hormones lack scientific support.

Individuals with pre-existing heart conditions must consult a physician before using thyroid hormones, always opting for the lowest effective dose.

Hormone Levels

Thyroid hormone levels are routinely monitored, especially in athletes, as organizations like the IOC and WADA conduct testing. Sensitive radioimmuno assays can detect low hormone levels in urine samples.

Drug Interactions

Liothyronine may interact adversely with various medications:

• Oral anticoagulants
• Insulin and oral hypoglycemics
• Cholestyramine
• Estrogen and oral contraceptives
• Tricyclic antidepressants
• Digitalis

Physicians must carefully manage dosages in these scenarios, with regular monitoring of patients on thyroid hormone.

Overdosage Treatment

In the event of suspected thyroid hormone overdose, hospital admission is critical. Hormone intake should be paused, and the patient monitored. Most need to cease the hormone for at least 4-8 weeks for recovery. Supportive care is paramount; inducing vomiting is discouraged due to aspiration risks. Comatose patients may require temporary ventilation, while fluid resuscitation, oxygen, and observation are typically sufficient. In some cases, beta-adrenergic blockers may be needed to mitigate sympathetic responses.

Dosage Information

Liothyronine is administered once daily, with dosage tailored to the degree of hypothyroidism. Treatment should commence at the lowest effective dose due to its rapid action; the initial dose for Cytomel is 5 mcg/day, increasing in 5 mcg increments every 2-3 weeks. Avoiding high starting doses is crucial, particularly for those with existing heart concerns. Generally, effective doses range from 50-75 mcg/day. An intravenous form of liothyronine is also available, especially for treating myxedema coma, a serious complication of hypothyroidism, predominantly affecting elderly women.

Liothyronine is offered in tablet strengths of 5, 25, and 50 mcg, and requires a physician’s prescription in the USA.