Core71: Drug-induced adverse reaction: sexual dysfunction

❤️ High-yield / 要点：Drug-induced sexual dysfunction commonly affects libido, erection, ejaculation, and orgasm. The most important culprits are SSRIs/SNRIs, antipsychotics, thiazides, β-blockers, α-blockers, statins, and oral contraceptives.

Main patterns / 主な症状

• Decreased libido.
• Erectile dysfunction.
• Difficult orgasm.
• Anorgasmia.
• Ejaculatory dysfunction.
• Dyspareunia.

Drug causes / 原因薬

Drug group	Examples	Main mechanism / pattern
SSRIs / SNRIs	Serotonin reuptake inhibitors	Decreased libido, erectile dysfunction, delayed orgasm, anorgasmia
Antipsychotics	D2 antagonists	Hyperprolactinemia → reduced FSH/LH axis activity → decreased libido/orgasm dysfunction
Thiazides	Thiazide diuretics	Erectile dysfunction due to hypovolemia
β-blockers	β-blockers	Erectile dysfunction
α-blockers	α-blockers	Reduced ejaculate, retrograde ejaculation, erectile dysfunction
HMG-CoA reductase inhibitors	Statins	Erectile dysfunction, reduced libido; possible reduced testosterone synthesis
Oral contraceptives	Combined oral contraceptives	Decreased libido, dyspareunia; reduced hypothalamic-pituitary-ovarian axis activity

Key mechanisms / 重要機序

• Serotonergic excess can impair libido and orgasm.
• D2 blockade can cause hyperprolactinemia and suppress gonadal axis function.
• Hypovolemia / hemodynamic change can worsen erectile function.
• α-blockade is classically linked to ejaculatory dysfunction.

Remember / 覚え方

• SSRIs = decreased libido + anorgasmia
• Antipsychotics = hyperprolactinemia-related dysfunction
• α-blockers = ejaculatory problems
• β-blockers/thiazides = erectile dysfunction