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

hCG 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.

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 hCG:

• twice weekly, injection (Human RCT; BJU international 2018, PMID 29772111)
• twice weekly, subcutaneous self-injection (Human RCT; The Journal of clinical endocrinology and metabolism 2002, PMID 12107212)

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

Drug tests and sport

Chorionic gonadotrophin (hCG) is prohibited for male athletes (S2.2.1, testosterone-stimulating peptides). The list limits this class to males.

Anti-doping labs use tests built for specific substances. Whether a given test detects hCG, and for how long, is not reported in the anti-doping literature we checked (as of 2 Oct 2026). Tested athletes should treat it as prohibited (s2.2.1) at all times.