Avodart (dutasteride) is a medication primarily used to treat benign prostatic hyperplasia (BPH), but it has also been used off-label in gender-affirming care, particularly for transgender women (assigned male at birth). Dutasteride is a 5-alpha-reductase inhibitor that blocks the conversion of testosterone to dihydrotestosterone (DHT), thereby reducing levels of DHT in the body. While it can be effective in reducing DHT levels and aiding in feminisation, it’s important to be aware of potential unwanted/adverse/side effects. Here are some of them:
| Side Effect | Description |
| Decreased libido | A decrease in libido (sex drive) can occur as a side effect of dutasteride treatment due to its impact on androgen levels. |
| Erectile dysfunction | Dutasteride may cause erectile dysfunction or difficulty achieving/maintaining erections in individuals assigned male at birth. |
| Breast tenderness and enlargement | Dutasteride can cause breast tenderness and enlargement due to its impact on hormone levels, promoting estrogenic effects. |
| Thinning hair | Dutasteride may lead to hair thinning or loss (alopecia) in some individuals, though it can also promote scalp hair regrowth in others. |
| Fatigue | Fatigue or feelings of lethargy may occur as a side effect of dutasteride treatment. |
| Mood changes | Some individuals may experience mood swings, depression, or changes in emotional well-being while taking dutasteride. |
| Gynecomastia | Dutasteride may cause breast development (gynecomastia) in individuals assigned male at birth, which may be desired but can also cause distress in some cases. |
| Testicular discomfort | Some individuals may experience discomfort or pain in the testicles while taking dutasteride. |
| Decreased semen volume | Dutasteride can reduce the volume of semen ejaculated during orgasm. |
| Rare allergic reactions | Although rare, some individuals may experience allergic reactions to dutasteride, including rash, itching, swelling, or difficulty breathing. Immediate medical attention is necessary if any signs of an allergic reaction occur. |