What OptiPin's sourced rule file says about Clenbuterol with T3 (clen and Cytomel): the combination first, then what each one adds alone, then one bloodwork plan for both. It names markers and red flags, never doses.
This page describes a pair, not you. If you have chest pain, trouble breathing, weakness or numbness on one side, yellowing of your skin or eyes, or shaking, sweating and confusion that could be low blood sugar, get urgent medical care now. Nothing here is a dose, a protocol or a safety verdict.
What the rules say about the combination
1 rule fires only when both compounds are present. Each card is rendered from OptiPin's public, sourced rule file. Its labels show the evidence behind each claim (how we label evidence).
Interaction · label or pharmacokinetic evidence for the combination
T3 with clenbuterol or ephedrine strains the heart Drug label
Flagged by: T3, Clenbuterol
The liothyronine label warns that thyroid hormone used for weight loss can be life-threatening at higher doses, particularly with sympathomimetic drugs. Clenbuterol and ephedrine are sympathomimetics.
Both raise heart rate and cardiac workload. The label flags the combination specifically.
Markers to check
Resting heart rate and blood pressure
TSH, free T4 and free T3
Get medical care for
Chest pain or pressure (emergency services)
A racing or irregular heartbeat that does not settle
Fainting or severe shortness of breath (emergency services)
Evidence
Strong: boxed warning and interaction section of the liothyronine label.
Every marker the rules above name, listed once. Take it to your clinician or lab.
Resting heart rate and blood pressure (T3 with clenbuterol or ephedrine strains the heart)
TSH, free T4 and free T3 (T3 with clenbuterol or ephedrine strains the heart)
Add anything else you run in the stack checker, which starts with this pair already filled in.
What each compound is
Clenbuterol. A potent beta-2 agonist that a 2023 systematic review describes as widely misused by athletes and bodybuilders.
T3 (liothyronine, Cytomel). A synthetic form of the thyroid hormone T3, approved for hypothyroidism. Its label carries a boxed warning against use for obesity or weight loss.
Log a cycle in OptiPin and it shows whether the stack converts to estradiol, which compounds are 19-nors or 17α-alkylated, when red cell count tends to climb and when your own production is shut down, each with the marker that reads it. All on-device.
The liothyronine label warns that thyroid hormone used for weight loss can be life-threatening at higher doses, particularly with sympathomimetic drugs. Clenbuterol and ephedrine are sympathomimetics. Both raise heart rate and cardiac workload. The label flags the combination specifically.
What is worth monitoring on Clenbuterol and T3?
Resting heart rate and blood pressure; TSH, free T4 and free T3.
When should someone on Clenbuterol and T3 get medical care?
Chest pain or pressure (emergency services); A racing or irregular heartbeat that does not settle; Fainting or severe shortness of breath (emergency services).
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