T3 (Liothyronine / Cytomel)
3,5,3'-Triiodothyronine. Thyroid Hormone, metabolic hormone.
This page describes what T3 (Liothyronine / Cytomel) is and its known risks. It is not medical advice and not a guide to using it. Many of these substances are prescription-only or illegal to use without a prescription. Speak to a doctor.
- Class
- Thyroid Hormone
- Legal status
- Prescription only
- Half-life
- 24 hours
- Liver strain
- Low
- Kidney strain
- Low
- Converts to estrogen
- None
- Suppresses natural hormones
- Not typically
Medical uses
- Hypothyroidism
- Thyroid cancer (suppression therapy)
- Myxedema coma
What it does in the body
Metabolic
- Increased metabolic rate
- Fat loss
- Increased body temperature
- Increased energy
- Enhanced nutrient partitioning
Forms, half-life and detection
| Form | Half-life | Reported detection window |
|---|---|---|
| Oral | 24 hours | Not tested |
Side effects and health risks
Hormones and fertility
- Thyroid suppression (potentially permanent)
- Thyroid atrophy
Heart and blood vessels
- Increased heart rate
- Palpitations
- Arrhythmias
- Increased blood pressure
- Increased risk of heart attack
Musculoskeletal
- Muscle loss (catabolic)
- Bone loss (osteoporosis risk)
Neurological
- Anxiety
- Insomnia
- Tremors
- Nervousness
Metabolic
- Hyperthyroidism symptoms
- Excessive sweating
- Heat intolerance
Related compounds
Questions
What is the half-life of T3 (Liothyronine / Cytomel)?
About 24 hours. Half-life is the time for the level in the blood to fall by half.
How long is T3 (Liothyronine / Cytomel) detectable?
Testing windows of Not tested are reported, depending on the test and the person.
Is T3 (Liothyronine / Cytomel) legal?
Prescription only. Laws differ by country and change; check the rules where you live.
What blood tests matter with T3 (Liothyronine / Cytomel)?
Ask a doctor which tests suit you.
What are the side effects of T3 (Liothyronine / Cytomel)?
Hormones and fertility: thyroid suppression (potentially permanent) and thyroid atrophy. Heart and blood vessels: increased heart rate, palpitations and arrhythmias. Musculoskeletal: muscle loss (catabolic) and bone loss (osteoporosis risk).
For information only, not medical advice. MyoStats is a tracking tool used at your own discretion. Speak to a doctor before changing your training, diet, medication or anything you take.