Testosterone-based hormones
Some transgender, Two-Spirit and non-binary people benefit from testosterone-based hormone therapy to align physical characteristics with their gender.
Testosterone-based therapies are also known as “masculinizing hormones.” To be more inclusive of diverse gender identities, we are using language that focuses on anatomy, treatments, goals and presenting concerns, rather than gender.
What is testosterone-based therapy?
Testosterone is a hormone that is used to induce secondary sex characteristics like beard growth and a deepened voice. It also reduces estrogen-related features, such as a rounder face shape or body fat around the hips and buttocks.
This page describes the advantages and disadvantages, expected effects, and potential risks of common testosterone therapies. The list of therapies is not exhaustive. Talk to your health care provider to determine the best fit for you.
Expected effects of testosterone-based hormone therapies
Increased sex drive
- Usually starts 1–3 months after beginning therapy
- Reversible change if you stop taking testosterone
Stopping monthly bleeding
- Depends on the dose of testosterone (some people on lower doses might still experience monthly bleeding)
- Cessation usually happens 1–6 months after beginning therapy
- You may still ovulate and be able to get pregnant even when your monthly bleeding stops (Note: it is not safe to take testosterone while pregnant)
- Reversible change, if you stop taking testosterone
Enlarging erectile tissue (clitoris) & genital tissue (labia)
- Usually starts 1–6 months after beginning therapy
- Reaches full size in 1–2 years
- Size typically ranges from 1–3 cm
- Likely a permanent change, even if you stop taking testosterone
Increased facial and body hair
- Usually starts 6–12 months after beginning therapy
- Maximum effect in 5+ years
- Gradual growth of facial hair
- More hair and thicker and coarser hairs on abdomen, arms, chest, back and legs
- Likely a permanent change, even if you stop taking testosterone
Scalp hair loss (balding)
- Usually starts less than 12 months after beginning therapy
- Can be more prominent if there is a family predisposition to hair loss
- Hair loss at temples and along the crown of head
- Possibility of becoming completely bald
- Likely a permanent change, even if you stop taking testosterone
- You can take medications to minimize this
Oily skin and acne
- Usually starts 1–6 months after beginning therapy
- Maximum effect in 1–2 years
- More acne and may permanently scar
- You can take medications to minimize this
- Not a permanent change
Increased muscle mass and strength
- Usually starts 6–12 months after beginning therapy
- Maximum effect in 2–5 years
- Not a permanent change
Body fat redistribution
- Usually starts 1–6 months after beginning therapy
- Maximum effect in 2–5 years
- More abdominal fat
- Less fat around buttocks, hips and thighs
- Not a permanent change
Deepened voice
- Usually starts 1–6 months after beginning therapy
- Maximum effect in 1–2 years
- While your voice may deepen, other aspects of the way you speak may not be aligned with your gender goals; you can work with a speech language pathologist to achieve this, if desired
- Permanent change
Changing the lining of internal genitals (vagina)
- Usually starts in 1–6 months
- Maximum effect in 1–2 years
- Thinning and drying of the lining of the internal genitals (vagina)
- May make certain activities (ranging from walking to having receptive sex) uncomfortable (treatments are available)
- Not a permanent change
Emotional changes
- Overall emotional state may or may not change; this varies from person to person
- Many people experience positive mood changes
- May experience a narrower range of emotions or feelings
- May become irritable, frustrated or angry more easily
- Not a permanent change
Risks associated with testosterone-based hormone therapies
Testosterone is known to increase the chances of polycythemia (increased red blood cells), weight gain, acne, balding and sleep apnea. Testosterone may affect your cardiovascular health by causing changes to cholesterol, blood pressure, blood sugar and weight. Testosterone may also exacerbate certain mental health concerns. There are other potential risks, depending on the specific medication you use and you should discuss these with your provider.
There is either no increased risk of bone density loss or cancer (chest or breast, cervical, ovarian, uterine), or the research is inconclusive.
If you inject testosterone, you may experience fluctuating emotions and energy levels due to variations in testosterone levels throughout the week. You may want to talk to your health care provider about switching to more frequent injections of smaller doses or topical testosterone. Any mood changes that cause you concern should be discussed with your health care provider.