Hormones & fertility · Libido
HCG, simplified.
Also called Human chorionic gonadotropin, Pregnyl, Novarel
Approved RxA pregnancy hormone that also tells the testes to make testosterone. It is an approved prescription for fertility and some hormone problems.
- Size
- Large hormone (protein), not a short peptide
- How it is taken
- Injection
- Status
- FDA-approved prescription
- Available sizes
- Vials: 5,000 IU
What is it?
HCG acts like LH, the brain’s signal to the testes or ovaries. In men, that means making testosterone and sperm. It is often used with testosterone therapy to keep natural production and fertility going.
Official prescribing information
Novarel and Pregnyl are FDA-approved. The official label shows how it was dosed in the trials that led to approval, along with warnings and who should not use it.
Doses on the label are for the approved product under a prescriber’s care. Talk with your doctor before starting anything.
What studies show
- In peopleIt raises testosterone in men whose testes are working but not getting the signal.
- In peopleIt helps preserve sperm production in men on testosterone therapy.
- In peopleTrials found the "HCG diet" does not cause weight loss beyond the low-calorie diet itself.
What we don’t know yet
- Best long-term approach alongside testosterone therapy.
Side effects and cautions
- Can cause breast tenderness, mood changes and acne from higher estrogen and testosterone.
- Not for use with hormone-sensitive cancers.
Is it legal?
FDA-approved. Available only with a prescription. The FDA does not approve it for weight loss.
Dosage & schedule evidence
How to read published schedules
Some hCG products have approved indications and product-specific prescribing instructions. Consult the current official product label and a clinician; third-party schedules are not a substitute.
| Measurement | Meaning |
|---|---|
| 1 mg | 1,000 mcg (mass) |
| 100 U-100 units | 1 mL (volume, not dose) |
See third-party published protocols ↗ for research context. North Star does not validate these schedules.
Consult your doctor before considering any peptide for personal use. Educational only, not administration guidance.
Common questions
What is HCG?
A pregnancy hormone that also tells the testes to make testosterone. It is an approved prescription for fertility and some hormone problems. HCG acts like LH, the brain’s signal to the testes or ovaries. In men, that means making testosterone and sperm. It is often used with testosterone therapy to keep natural production and fertility going.
What does the research say about HCG?
It raises testosterone in men whose testes are working but not getting the signal. It helps preserve sperm production in men on testosterone therapy. Trials found the "HCG diet" does not cause weight loss beyond the low-calorie diet itself.
Is HCG FDA approved?
FDA-approved. Available only with a prescription. The FDA does not approve it for weight loss.
What are the side effects of HCG?
Can cause breast tenderness, mood changes and acne from higher estrogen and testosterone. Not for use with hormone-sensitive cancers.
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This page explains published research in plain language. It is not medical advice, a diagnosis, or a recommendation to take anything, and it does not give dosing. Most peptides here are not FDA-approved, and products sold online vary widely in purity. Rules around peptides are changing, so check the current status and talk with a licensed clinician before starting anything. Last reviewed 2026-10-19.