HCG

Key points

• hCG is a natural hormone made in pregnancy. As a medicine it acts like luteinising hormone (LH), the signal that tells the testes or ovaries to work.
• It is a licensed, prescription only medicine in the UK, used for some fertility treatment and certain cases of low testosterone caused by the pituitary.
• It is prescribed and dispensed through registered providers after an assessment. It is not something to buy online.
• It is prohibited for male athletes in sport, and hCG weight loss products are not supported by evidence.

Quick facts

What it is

Human chorionic gonadotropin, a gonadotropin hormone

Licensed use

Fertility; certain low testosterone from the pituitary

UK status

Licensed, prescription only medicine

Weight loss

Not supported by evidence; products warned against

In sport

Prohibited for male athletes

How it works

hCG binds the same receptors as luteinising hormone. In men it prompts the testes to make testosterone directly, which is why it is used when the brain's own signal to the testes is low or has been suppressed. In women it can stand in for the mid cycle surge that triggers the release of an egg. It lasts a while in the body, so it is usually given every few days rather than daily.

What the evidence shows

The strongest evidence is in men whose low testosterone comes from the pituitary, where gonadotropin treatment has been used for decades to restore testosterone and support fertility. Its use in fertility treatment is also well established. Uses alongside testosterone therapy, or to restart the body's own production afterwards, rest on smaller, less controlled studies. For weight loss, trials and reviews have found no benefit beyond eating less, and regulators have said so.

What it does not settle

• The best doses and schedules for uses outside the licensed ones are not well established.
• Recovery of fertility after testosterone or steroid use can take months and does not succeed for everyone.
• Long term outcomes of combining hCG with testosterone are not well documented.

Side effects

Common

• Headache, restlessness or low mood, tiredness, fluid retention, and pain at the injection site.
• In men, tenderness or enlargement of breast tissue can occur.

Less common but serious

• Allergic reactions can occur, and caution is needed with heart, kidney, migraine, epilepsy or asthma conditions because of fluid retention.
• It should not be used by people with a hormone driven cancer such as prostate cancer, and it can interfere with some hormone blood tests.

Report any suspected side effect through the MHRA Yellow Card scheme.

UK legal status and access

hCG is a licensed prescription only medicine in the UK. A registered prescriber must assess you first, and it is dispensed as a licensed product through a pharmacy. Vials sold online for research use are of unverified strength and sterility, and because the dose is measured by biological activity, a label cannot be trusted.

Common questions