Adverse effects of common medications on male fertility

An increasing number of patients require long-term medication regimens at a young age, but the adverse effects of medications on male reproduction are often inadequately considered, recognized and investigated. Medications can affect male reproduction through central hormonal effects, direct gonadotoxic effects, effects on sperm function or on sexual function. For example, exogenous testosterone inhibits spermatogenesis through central suppression of the hypothalamic-pituitary-gonadal hormonal axis. 5α-reductase inhibitors can impair sexual function, decrease semen volume and negatively affect sperm parameters, depending on dose and treatment duration. α-Blockers might decrease seminal emission and cause retrograde ejaculation, depending on the receptor specificity and dose of the agent. Phosphodiesterase inhibitors seem to have variable effects based on the isoform inhibited and evidence is conflicting. Antihypertensive and psychotropic agents can affect sperm, sexual function and hormonal parameters. For antibiotics, the literature on effects on sperm and sperm function is limited and dated. Many chemotherapeutic agents have a direct gonadotoxic effect, depending on agents used, dosing and number of treatment cycles. Overall, many medications commonly used in urology can have effects on male fertility (mostly reversible) but conclusive evidence in humans is often limited. Men should be counselled appropriately about potential drug-related adverse effects on their fertility.