Multiple sclerosis and erectile dysfunction frequently occur together, but the connection is rarely explained by a single damaged nerve or one abnormal hormone level. An erection depends on coordinated sensory input, brain and spinal-cord signaling, autonomic nerve activity, blood-vessel relaxation, pelvic-floor function, and psychological arousal. Multiple sclerosis (MS) can affect several of these systems at once. Recent reviews suggest that erectile problems affect roughly half of men with MS, although estimates vary with age, disability, disease duration, and how sexual function is measured.[1,2]
Why Multiple Sclerosis and Erectile Dysfunction Overlap
MS is an immune-mediated disorder in which inflammation damages myelin and, in some cases, the underlying nerve fibers within the central nervous system. Because sexual response involves pathways running through the brain, brainstem, and spinal cord, the location and burden of MS lesions can influence erection, genital sensation, orgasm, and ejaculation.
Clinicians often describe sexual dysfunction in MS as primary, secondary, or tertiary. Primary effects arise directly from neurologic injury. Demyelination may interrupt descending autonomic signals that initiate penile smooth-muscle relaxation or alter sensory signals traveling upward from the genitals. A man may notice reduced sensation, slower arousal, inconsistent rigidity, or difficulty maintaining an erection even when desire remains intact.
Secondary effects come from other MS symptoms or their treatment. Fatigue can reduce sexual energy and make timing important. Spasticity, weakness, pain, tremor, bladder urgency, bowel symptoms, and reduced mobility can interfere with comfort and confidence. Medications used for depression, pain, spasticity, bladder dysfunction, or sleep may also affect libido, erection, or ejaculation. These effects are not inevitable, and a medication should never be stopped without speaking with the prescribing clinician.
Tertiary effects involve mood, self-image, relationship strain, and social context. Depression and anxiety are common in chronic neurologic disease and can directly suppress sexual interest and arousal. Fear of bladder leakage, fatigue during sex, or a previous unsuccessful attempt can create anticipatory anxiety. That anxiety increases sympathetic nervous-system activity—the physiologic “fight or flight” state—which works against the parasympathetic signaling needed for erection.
What Recent Research Shows
A 2025 systematic review and meta-analysis in The Journal of Sexual Medicine included 61 studies and 16,266 people with MS. Men with MS had significantly lower International Index of Erectile Function scores than healthy controls. Across the broader MS population, reduced sexual function was associated with longer disease duration, greater disability, and depression.[1] These associations do not prove that disability or depression alone causes ED, but they reinforce the need to assess sexual symptoms as part of the whole disease burden.
A 2024 scoping review focused specifically on male sexual and reproductive health in MS. Across 34 studies, sexual dysfunction was reported in approximately 35% to 72% of men, with erectile dysfunction and reduced libido among the most common concerns.[2] The range is wide because studies used different definitions, populations, and questionnaires. The review also found that relatively few men discussed sexual health with their treatment teams, despite its relationship with quality of life.
In a 2024 case-control study, Adamec and colleagues assessed erectile dysfunction and premature ejaculation in men with MS using validated instruments. Higher Expanded Disability Status Scale scores predicted a greater likelihood of ED, while the presence of a cremasteric reflex was associated with lower odds.[3] The finding supports a neurologic contribution, but it should not be used as a stand-alone diagnostic test. Erectile function still depends on vascular, hormonal, medication-related, and psychological factors that may coexist with MS.
Earlier pooled research estimated ED prevalence near 49% in men with MS.[4] Prevalence is not the same as inevitability: many men with MS retain normal erectile function, and some experience symptoms only during relapses, periods of severe fatigue, or medication changes. The practical message is that ED is common enough to ask about routinely and complex enough to evaluate individually.
How MS Can Disrupt the Erection Pathway
Normal erection begins when erotic thoughts or genital stimulation activate neural pathways that release nitric oxide in penile tissue. Nitric oxide increases cyclic guanosine monophosphate (cGMP), which relaxes smooth muscle in the corpora cavernosa. Arterial inflow rises, expanding erectile tissue and compressing the veins that normally drain the penis.
MS may interfere upstream of that vascular response. Lesions above the sacral spinal cord can disrupt psychogenic erections initiated by visual, emotional, or cognitive stimulation. Sacral pathway involvement can impair reflexogenic erections triggered by direct touch. The pattern differs between individuals because lesion location, inflammatory activity, and neurologic reserve differ.
Autonomic dysfunction may further alter heart rate, blood-pressure regulation, and genital blood-flow responses. At the same time, conventional vascular risks remain important. Men with MS can also have hypertension, diabetes, high cholesterol, smoking exposure, obesity, or low physical activity. These factors reduce endothelial nitric-oxide availability regardless of neurologic diagnosis. ED should therefore not automatically be attributed to MS without assessing cardiovascular and metabolic health.
Hormones can contribute, but testosterone is not a universal explanation. Testing may be appropriate when ED occurs with low libido, fewer morning erections, reduced body hair, loss of muscle mass, or unexplained fatigue. A morning total testosterone result that is low generally requires confirmation and clinical interpretation. Thyroid disease, elevated prolactin, and diabetes may also warrant targeted evaluation based on symptoms and history.
Evaluation: Looking Beyond a Single Symptom
The most useful evaluation starts with a precise history. Clinicians may ask whether the problem involves desire, rigidity, maintenance, orgasm, ejaculation, sensation, or several domains. The timing matters: a sudden change after a new medication suggests a different pathway than gradual decline alongside worsening mobility or vascular risk.
Validated questionnaires such as the five-item Sexual Health Inventory for Men can quantify severity and track response, but they do not identify the cause. A review should include prescription and nonprescription medications, alcohol and nicotine use, sleep, mood, bladder symptoms, pain, fatigue, relationship context, and whether erections occur during sleep or masturbation.
A focused examination may assess blood pressure, peripheral pulses, genital anatomy, sensation, reflexes, and signs of endocrine disease. Laboratory testing is individualized but may include fasting glucose or A1c, lipids, and morning testosterone. The neurology team can help determine whether new sexual symptoms appeared with other signs of relapse or progression. Urology input may be useful when the diagnosis is uncertain, first-line treatment fails, penile curvature or pain is present, or specialized testing is being considered.
New ED is sometimes a vascular warning sign even in a man with an established neurologic condition. Chest pain, major exercise intolerance, or symptoms of vascular disease deserve medical assessment before sexual activity or ED treatment. Sudden neurologic changes, new weakness, major sensory loss, or acute bladder dysfunction require prompt review rather than being managed as an isolated sexual concern.
Treatment Options and Clinical Limits
Treatment should match the dominant mechanisms. Modifiable contributors may include poor sleep, depression, heavy alcohol use, nicotine exposure, inadequate physical activity, and uncontrolled cardiometabolic disease. Energy conservation can be surprisingly practical: some couples plan intimacy for a time of day when fatigue and spasticity are lowest. Bladder emptying beforehand, comfortable positioning, temperature control, and open communication may reduce secondary barriers without medicalizing every aspect of sex.
When medication is suspected, the goal is a supervised review—not abrupt discontinuation. Some antidepressants, antispasticity agents, sedatives, opioids, and bladder medications can affect sexual response. Depending on the indication, a clinician may adjust the dose, timing, or agent while protecting neurologic and mental-health stability.
Phosphodiesterase type 5 (PDE5) inhibitors support the nitric oxide–cGMP pathway by slowing cGMP breakdown. They require sexual stimulation and do not directly create desire. In a 12-week randomized, double-blind trial involving 217 men with MS and ED, 89% of participants receiving sildenafil reported improved erections versus 24% receiving placebo; measures of erection quality and quality of life also improved.[5] However, later reviews have emphasized that the MS-specific evidence base remains limited, individual response varies, and larger contemporary trials are needed.[2]
PDE5 inhibitors are not appropriate for everyone. They must not be combined with nitrate medications because the interaction can cause a dangerous blood-pressure drop. Caution is also required with certain alpha-blockers, substantial cardiovascular disease, and some blood-pressure or drug interactions. Headache, flushing, nasal congestion, indigestion, and dizziness are common adverse effects. Any erection lasting four hours or longer requires emergency care.
If tablets do not provide adequate benefit, clinicians may revisit dose timing, stimulation, adherence, and the underlying diagnosis before labeling treatment failure. Vacuum erection devices, intraurethral or intracavernosal medication, counseling or sex therapy, and penile implants are options in selected cases. Reduced genital sensation, severe spasticity, pain, and relationship distress may need parallel treatment because stronger vascular therapy alone cannot correct every part of MS-related sexual dysfunction.
Conclusion
Multiple sclerosis can affect erections through neural injury, autonomic changes, fatigue, disability, medications, mood, and relationship pressures, while ordinary vascular and hormonal risks remain relevant. The evidence indicates that ED is common in men with MS, but it is neither unavoidable nor too minor to discuss. A structured assessment can separate neurologic, vascular, endocrine, medication-related, and psychological contributors and lead to treatment that fits the individual rather than the diagnosis alone.
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These statements have not been evaluated by the FDA. This content is for informational purposes only and does not constitute medical advice.
References
- Yazdan Panah M, Oraee S, Fekri M, et al. Sexual function in people with multiple sclerosis: a systematic review and meta-analysis. The Journal of Sexual Medicine. 2025;22(7):1122–1138. doi:10.1093/jsxmed/qdaf102
- Toljan K, Briggs FBS. Male sexual and reproductive health in multiple sclerosis: a scoping review. Journal of Neurology. 2024;271(5):2169–2181. doi:10.1007/s00415-024-12250-2
- Adamec I, Sambolić T, Santini M, et al. Characteristics and predictors of sexual dysfunction in men with multiple sclerosis. Multiple Sclerosis and Related Disorders. 2024;85:105531. doi:10.1016/j.msard.2024.105531
- Shaygannejad V, Mirmosayyeb O, Vaheb S, Nehzat N, Ghajarzadeh M. The prevalence of sexual dysfunction and erectile dysfunction in men with multiple sclerosis: a systematic review and meta-analysis. Neurología (English Edition). 2025;40(1):22–31. doi:10.1016/j.nrleng.2022.08.002
- Fowler CJ, Miller JR, Sharief MK, Hussain IF, Stecher VJ, Sweeney M. A double blind, randomised study of sildenafil citrate for erectile dysfunction in men with multiple sclerosis. Journal of Neurology, Neurosurgery & Psychiatry. 2005;76(5):700–705. doi:10.1136/jnnp.2004.038695
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