- Testosterone is a sex hormone that directly builds muscle; HGH (somatropin) is a growth hormone that works mostly through IGF-1.
- On its own, HGH adds little muscle in healthy adults; it mainly reduces fat and increases lean mass that is partly water.
- Their side effects differ: testosterone affects estrogen, blood and lipids; HGH affects blood sugar, joints and fluid.
- In Canada, testosterone is a Schedule IV steroid; HGH is a prescription drug that isn’t listed in the Controlled Drugs and Substances Act.
Testosterone and human growth hormone are often mentioned together, sometimes as if they were interchangeable. They’re not. This guide explains what each hormone does, what research shows when they’re combined, the different risks, and how their legal status differs in Canada.
Two different hormones
| Testosterone | HGH (somatropin) | |
|---|---|---|
| Type | Steroid sex hormone | Peptide hormone from the pituitary |
| Main action | Directly on androgen receptors in muscle | Mostly via IGF-1 made in the liver |
| Muscle in healthy adults | Clear, dose-dependent gains | Modest; some gain is fluid |
| Fat loss | Moderate | Notable, especially abdominal |
| Given by | Intramuscular injection, gel, others | Subcutaneous injection |
| Canadian status | Prescription; Schedule IV CDSA | Prescription; not CDSA-listed |
What the research shows
Studies in healthy adults show that growth hormone alone increases lean body mass and reduces fat, but the lean mass gain is partly water, and strength often doesn’t improve much. Testosterone, by contrast, increases muscle size and strength in a dose-dependent way. In older men given both, the combination produced larger changes in body composition than either alone, along with more side effects.
Medical uses
Testosterone is prescribed for hypogonadism (low testosterone). See our TRT in Canada guide.
Somatropin is prescribed for growth hormone deficiency in children and adults, Turner syndrome, Prader-Willi syndrome and some other conditions, after specialist testing. It isn’t approved for anti-aging or athletic use.
Side effects compared
Testosterone
- Higher estradiol: water retention, gynecomastia
- Higher hematocrit, lower HDL, higher blood pressure
- Suppressed natural testosterone and fertility
HGH
- Fluid retention and swelling in hands and feet
- Joint and muscle aches, carpal tunnel symptoms
- Insulin resistance and higher blood sugar, a concern for anyone with diabetes risk
- With long, high-dose use, features of acromegaly (enlarged hands, feet, jaw) and organ growth
Our HGH guide covers these in detail.
Monitoring
- Testosterone users: testosterone, estradiol, CBC, lipids, liver function, blood pressure
- HGH users: IGF-1, fasting glucose and HbA1c, thyroid function, blood pressure
Ask your family doctor or book at LifeLabs or Dynacare.
Testing in sport
Both are prohibited under the World Anti-Doping Code, enforced in Canada by the Canadian Centre for Ethics in Sport. Testosterone use is detected through urine profiles; HGH has dedicated blood tests with a shorter detection window.
Buying in Canada
We stock Human Growth Hormone (10 vials of 10 IU, with bacteriostatic water) and testosterone from Zionova and Genetix on our injectables page. HGH is a prescription drug in Canada but isn’t listed in the Controlled Drugs and Substances Act; testosterone is Schedule IV, where personal possession isn’t an offence and trafficking, importing and exporting are.
Frequently asked questions
Is HGH better than testosterone for muscle?
No. In healthy adults testosterone builds far more muscle and strength; HGH mainly reduces fat and adds lean mass that is partly water.
Why do people take testosterone and HGH together?
They work through different pathways, and research shows larger body composition changes combined, along with more side effects.
Is HGH legal in Canada?
It’s a prescription drug but isn’t listed in the Controlled Drugs and Substances Act.
Does HGH raise testosterone?
Not meaningfully. They’re separate hormone systems.
Products mentioned in this guide
This article is general information for adults in Canada, not medical advice. Talk to a doctor or pharmacist before using any prescription drug, anabolic steroid or research compound, and get bloodwork done. If you’re in crisis, call or text 9-8-8 (Suicide Crisis Helpline) any time.
