The potential side effects of TRT depend primarily on the preparation used, the method of administration, the dosage, and the individual’s response to treatment. Possible effects include skin changes such as acne or oilier skin, fluid retention, hair loss, testicular atrophy, infertility, dependence, mood swings, or changes in libido.

With all three forms of therapy, excessive dosing can lead to hormonal imbalances that may manifest in different ways. Injections and gels generally tend to be associated with more frequent side effects, while side effects with oral therapy are generally less pronounced and can usually be well controlled when treatment is closely monitored by a physician.