Multiple sclerosis is a chronic immune-mediated inflammatory disease of the central nervous system. Immune cells attack myelin in the brain, spinal cord, and optic nerves. Demyelinated areas (plaques) slow or block nerve conduction; over time, axons are lost and disability accumulates. Peripheral nerves are not involved.

Who is affected: usually diagnosed between ages 20 and 40; about 2–3 times more common in women. Risk factors: low vitamin D and low sun exposure, Epstein-Barr virus infection, smoking, obesity in adolescence, and genetic susceptibility.

Clinical courses

A relapse is a new or worsening neurologic symptom lasting more than 24 hours without fever or infection, at least 30 days after a previous attack. A pseudo-relapse is temporary worsening of old symptoms from heat, fever, infection (often a UTI), or stress.

Uhthoff phenomenon: a rise in body temperature (hot bath, exercise, fever, hot weather) temporarily worsens existing symptoms because heat further slows conduction in demyelinated nerves. Symptoms resolve when the client cools down.

Symptoms vary with lesion location and may come and go.

• Visual: optic neuritis — sudden or subacute vision loss in one eye with pain on eye movement, blurred or dim vision, reduced color vision (colors look washed out); diplopia; nystagmus.
• Sensory: numbness, tingling, "pins and needles"; Lhermitte sign — electric-shock sensation down the spine when the neck flexes.
• Motor: weakness, spasticity, muscle spasms, hyperreflexia, Babinski sign.
• Cerebellar: ataxia, intention tremor, poor balance, dysarthria (scanning speech).
• Fatigue — the most common and often most disabling symptom; worse in heat and later in the day.
• Bladder: from spinal cord lesions that disrupt the pathways between the brain and the sacral micturition center. Overactive (spastic) bladder causes urgency, frequency, and incontinence; impaired emptying or sphincter dyssynergia causes hesitancy, incomplete emptying, and retention — often both together, raising UTI risk.
• Bowel: constipation, sometimes urgency.
• Sexual dysfunction.
• Cognitive changes: slowed processing, poor memory and attention, difficulty multitasking.
• Mood: depression is common; emotional lability (pseudobulbar affect) can occur.
• Pain: neuropathic pain, trigeminal neuralgia (bilateral trigeminal neuralgia in a young adult suggests MS).

MS is diagnosed by showing lesions in different CNS regions (dissemination in space) and, in many cases, at different times (dissemination in time), after excluding other causes. Under the 2024 revision of the McDonald criteria, the optic nerve is now a fifth region, and dissemination in time is no longer required when enough regions are involved or supportive markers are present (CSF oligoclonal bands or kappa free light chain index, central vein sign on MRI).

Treating a relapse

• High-dose IV methylprednisolone (commonly 1 g daily for 3–5 days) or equivalent oral dosing, sometimes followed by an oral taper. Speeds recovery but does not change long-term course.
• Adverse effects: hyperglycemia, mood and mental status changes (euphoria, insomnia, agitation, psychosis), fluid retention and hypertension, hypokalemia, GI irritation, infection risk, metallic taste. Monitor glucose and BP; give with food or acid suppression as ordered. Ask before giving if active infection is present; teach clients not to stop an oral taper abruptly.
• Plasma exchange for severe relapses not responding to steroids.

Disease-modifying therapies (DMTs) reduce relapses and new lesions; they do not repair damage. Current practice favors starting early, and many clinicians choose higher-efficacy agents early for active disease.

Pregnancy planning: many DMTs must be stopped before conception; relapse rates tend to fall during pregnancy and rise after delivery.

Symptom management

• Spasticity: baclofen (first-line oral) — drowsiness, dizziness, weakness; do not stop abruptly (withdrawal can cause seizures, hallucinations, high fever — especially with intrathecal pumps). Tizanidine — hypotension, sedation, liver toxicity; avoid with ciprofloxacin or fluvoxamine (CYP1A2 interaction). Stretching and physical therapy.
• Walking: dalfampridine — improves walking speed; seizure risk; contraindicated with a seizure history or moderate to severe kidney impairment.
• Fatigue: energy conservation, exercise, cooling, treat sleep problems and depression; amantadine or modafinil are sometimes used.
• Bladder: overactive bladder — anticholinergics (monitor retention, confusion, constipation) or mirabegron; incomplete emptying — clean intermittent self-catheterization; check post-void residual.
• Neuropathic pain: gabapentin, pregabalin, duloxetine, or TCAs.
• Depression: SSRIs, counseling.

Listed in priority order.

1. Airway and aspiration safety (advanced disease or brainstem involvement)
   • Swallow assessment; upright for meals; watch for choking and aspiration.
2. Safety and mobility
   • Fall prevention: assistive devices, clear pathways, grab bars, adequate lighting.
   • Provide visual cues and feedback while walking — watching the feet and floor markings helps clients with impaired position sense; physical therapy for balance and gait training.
   • Avoid prolonged bed rest — it worsens weakness and spasticity.
   • Diplopia: patch alternating eyes.
3. Relapse therapy monitoring
   • Glucose, BP, mood and mental status, sleep, signs of infection during high-dose steroids.
4. Elimination
   • Post-void residual; timed voiding; teach intermittent self-catheterization when ordered; fluid intake of about 1.5–2 L/day (do not restrict fluids to control urgency — raises UTI risk); bowel program with fiber and fluids.
5. Fatigue and energy conservation
   • Help the client prioritize activities, schedule demanding tasks for times of best energy, and plan rest periods; use adaptive equipment.
6. Temperature control — avoid hot baths, saunas, and overheating; cooling vests; treat fever promptly.
7. Cognition
   • Provide new information in writing, use calendars, lists, and phone reminders, keep a structured daily routine, minimize distractions, and teach one task at a time.
8. Skin — sensory loss and immobility raise pressure-injury risk; check skin daily.
9. Psychosocial — screen for depression and suicide risk; connect to support groups and vocational resources.

• MS is chronic and variable; DMTs work best when taken consistently — do not stop without talking to the neurologist.
• Injection technique, site rotation, and premedication for interferon flu-like symptoms.
• Report new symptoms lasting more than 24 hours (possible relapse) and signs of infection, especially UTI.
• Avoid overheating — cool showers, air-conditioning, and cooling garments; temporary heat-related worsening is expected to pass.
• Regular exercise (including aquatic exercise in cool water) improves strength, fatigue, and mood.
• Stop smoking; keep vitamin D sufficient as advised.
• Vaccinations: inactivated vaccines are generally recommended; live vaccines may be contraindicated on some DMTs — check first.
• Do not stop baclofen suddenly.
• Family planning discussion before pregnancy.

• MS = CNS demyelination (brain, spinal cord, optic nerve); women, age 20–40.
• Optic neuritis: sudden vision loss in one eye with pain on eye movement, reduced color vision.
• Uhthoff phenomenon: heat temporarily worsens symptoms — avoid overheating.
• MRI: periventricular white-matter lesions; CSF oligoclonal bands (LP supports diagnosis).
• Relapse: high-dose IV methylprednisolone → monitor hyperglycemia and mood/mental status.
• Interferon beta: established first-line RRMS injection — flu-like symptoms, depression, liver enzymes, CBC.
• Spasticity: baclofen first-line; never stop abruptly.
• Fatigue: prioritize activities, energy conservation, cooling.
• Bladder: urgency and incomplete emptying from spinal cord lesions; check post-void residual; intermittent self-catheterization.
• Gait: visual cues, assistive devices, physical therapy; avoid bed rest.
• Cognition: written information and structured routines.