Tesamorelin Half-Life: How Long It Stays in Your System

Tesamorelin half-life

A half-life depends on the route (under the skin, into a vein, by mouth or nasal spray) and the species it was measured in, so we report each value with its route and source.

Other pharmacokinetic findings (these are not half-life values):

What half-life means

Half-life is the time it takes for the amount of a drug in the blood to fall by half. After one half-life, about 50% is left; after two, about 25%; after four to five, only a few percent remain.

• A long half-life lets a drug be dosed less often, for example once a week.
• A short half-life means levels rise and fall quickly, which is why some peptides are given daily or more often.
• Effects can outlast blood levels, so half-life alone does not tell you how long a drug works.

What it means for dosing frequency

Dosing intervals used in published studies of Tesamorelin:

• not stated, not stated (Human controlled trial; eNeurologicalSci 2026, PMID 42382101)
• once daily, subcutaneous (once daily, per abstract) (Human RCT; The lancet. HIV 2019, PMID 31611038)
• not stated, not stated (Human RCT; The Journal of frailty & aging 2019, PMID 31237318)
• daily, subcutaneous (Human RCT; Clinical pharmacokinetics 2015, PMID 25358450)

Changing the interval changes how much drug builds up between doses, so it is not a free choice.

Drug tests and sport

Tesamorelin is named as a GHRH analogue in S2.2.4 (growth hormone releasing factors), prohibited at all times. Tesamorelin is also an FDA-approved medicine; an athlete would need a therapeutic use exemption.

Detection findings from anti-doping analytical studies:

• A urine assay detects CJC-1295 and other GHRH analogues at very low concentrations. · PMID 35298973
• Labs expect GHRH analogues like CJC-1295 to be hard to find because of tiny urine concentrations; the study reports no detections in routine anti-doping samples. · PMID 34665524

Tested athletes should treat it as prohibited (s2.2.4) at all times.