What causes erectile dysfunction in men?
Difficulty achieving or maintaining an erection—clinically termed erectile dysfunction (ED)—is a common condition affecting men of all ages, though prevalence increases with age. ED is defined as the persistent inability to attain and/or sustain a penile erection sufficient for satisfactory sexual performance, occurring over a period of at least several months.
Underlying causes are often multifactorial and may be broadly categorized as organic, psychological, or mixed. Organic contributors include cardiovascular disease (e.g., atherosclerosis impairing penile blood flow), diabetes mellitus (causing endothelial dysfunction and neuropathy), hypertension, dyslipidemia, obesity, metabolic syndrome, hormonal imbalances (notably low testosterone, hyperprolactinemia, or thyroid disorders), neurological conditions (e.g., multiple sclerosis, spinal cord injury, Parkinson’s disease), pelvic surgery or trauma, and chronic kidney or liver disease. Certain medications—including selective serotonin reuptake inhibitors (SSRIs), antihypertensives (e.g., beta-blockers, thiazides), antipsychotics, and opioids—can also contribute.
Psychological factors such as performance anxiety, depression, chronic stress, relationship conflict, or past sexual trauma may independently cause or exacerbate ED, particularly in younger men without comorbid medical conditions. Lifestyle factors—including tobacco use, excessive alcohol consumption, sedentary behavior, poor sleep hygiene, and illicit drug use—further increase risk.
A thorough clinical evaluation is essential and typically includes a detailed sexual, medical, and psychosocial history; physical examination focusing on cardiovascular, neurological, and genitourinary systems; and targeted laboratory testing (e.g., fasting glucose, lipid panel, total and free testosterone, prolactin, thyroid-stimulating hormone). In select cases, specialized testing—such as nocturnal penile tumescence monitoring, intracavernosal injection testing, or penile Doppler ultrasound—may be warranted.
Management is individualized and evidence-based. First-line interventions often include lifestyle modification (e.g., smoking cessation, structured exercise, weight management), optimization of comorbid conditions, and pharmacotherapy with phosphodiesterase type 5 inhibitors (PDE5is) such as sildenafil, tadalafil, vardenafil, or avanafil. For men unresponsive to or contraindicated for PDE5is, alternative options include intraurethral alprostadil, intracavernosal injections, vacuum erection devices, or, in refractory cases, penile prosthesis implantation. Psychological support—including cognitive behavioral therapy or sex therapy—is strongly recommended when psychogenic factors are prominent.
Importantly, ED can serve as an early warning sign of systemic vascular disease—often preceding coronary artery disease by 2–5 years. Therefore, its identification presents a valuable opportunity for comprehensive cardiovascular risk assessment and preventive intervention.