I have a right-sided headache with blurry vision, what should I do?

Right-Sided Headache with Blurry Vision: Immediate Action Required

You need urgent evaluation to rule out vision-threatening and life-threatening causes before assuming this is a benign primary headache—specifically, measure intraocular pressure immediately to exclude acute angle-closure glaucoma, perform funduscopy to assess for papilledema, and evaluate for stroke or transient ischemic attack given the unilateral presentation. 1, 2

Step 1: Immediate Red Flag Assessment

Seek emergency care immediately if any of the following are present:

• Thunderclap onset (sudden, severe headache reaching maximum intensity within seconds to minutes) suggests subarachnoid hemorrhage 2, 3, 4
• Unilateral vision loss or monocular blindness in the right eye with right-sided headache suggests carotid artery territory ischemia or stroke 2
• Severely elevated eye pressure with halos around lights, mid-dilated pupil, and corneal cloudiness indicates acute angle-closure glaucoma requiring treatment within hours to prevent permanent blindness 1
• Papilledema (optic disc swelling) on funduscopic examination suggests elevated intracranial pressure 1
• Fever, neck stiffness, or altered consciousness raises concern for meningitis or encephalitis 5, 4
• Progressive worsening pattern or new onset after age 50 requires urgent neuroimaging 6, 5

Step 2: Emergency Department Evaluation Protocol

If you present to emergency care, expect the following workup:

• Immediate ophthalmologic consultation with intraocular pressure measurement (normal <21 mmHg; acute angle-closure typically >40 mmHg) and gonioscopy to assess anterior chamber angle 1
• Funduscopic examination to identify papilledema, which when present with normal neuroimaging confirms idiopathic intracranial hypertension (opening pressure >25 cm H₂O on lumbar puncture) 1
• Neurological examination focusing on motor weakness (right-sided headache with left-sided weakness suggests right hemisphere stroke), visual field defects, and cranial nerve function 2
• Non-contrast head CT immediately if thunderclap onset, neurological deficits, or altered mental status are present 5
• Lumbar puncture with spectrophotometric analysis if CT is negative but subarachnoid hemorrhage remains suspected 5

Step 3: If Vision-Threatening Causes Are Excluded—Consider Migraine with Aura

Migraine with aura is the most likely diagnosis if:

• Visual symptoms (blurry vision, scintillations, zigzag lines, or scotoma) develop gradually over 5-20 minutes and last 5-60 minutes 2
• Visual symptoms are followed within 60 minutes by unilateral headache 2
• At least one aura symptom is unilateral (right-sided in your case) 2
• Headache has pulsating quality, moderate-to-severe intensity, or worsens with routine physical activity 2
• You have photophobia (light sensitivity) or phonophobia (sound sensitivity) 2

Critical distinction: Do NOT take triptans during the aura phase—wait until headache begins, as no evidence supports triptan use during aura and early treatment during aura may be ineffective 2

Step 4: Acute Treatment Algorithm (After Emergent Causes Excluded)

First-line treatment when headache begins:

• Naproxen sodium 500-825 mg or ibuprofen 400-800 mg at headache onset while pain is still mild 2, 1, 6
• Alternative: Aspirin 900-1000 mg + acetaminophen + caffeine combination 2, 6

Second-line treatment if NSAIDs provide inadequate relief:

• Triptan therapy (sumatriptan, rizatriptan, or eletriptan)—take early when headache is mild, NOT during aura phase 2
• If one triptan fails after adequate trial (no response in at least 3 consecutive attacks), try a different triptan as others may still provide relief 2
• Sumatriptan subcutaneous injection is most effective for rapid peak intensity or when vomiting prevents oral medication 2

Adjunctive therapy:

• Metoclopramide 10 mg taken 20-30 minutes before NSAID for synergistic analgesia and nausea control 1, 5

Step 5: Critical Medication Overuse Prevention

Restrict ALL acute migraine medications to maximum 2 days per week to prevent medication-overuse headache, which paradoxically increases headache frequency and can lead to daily headaches 1, 6, 5

Step 6: When to Seek Neurologist Referral

Refer to neurology if:

• Diagnosis remains uncertain after thorough evaluation 6, 7
• Motor weakness develops with headache 6, 7
• Persistent aura (visual symptoms lasting >60 minutes) occurs 6, 7
• Poor response to preventive strategies after adequate trials 6
• Headaches occur ≥2 days per month causing significant disability despite optimized acute treatment (consider preventive therapy with propranolol 80-160 mg daily, topiramate, or CGRP monoclonal antibodies) 6, 5

Common Pitfalls to Avoid

• Do not dismiss unilateral headache with visual symptoms as "just migraine" without first excluding stroke/TIA, especially if this is a new pattern—right-sided headache with visual changes can represent right carotid territory ischemia 2
• Do not delay ophthalmologic evaluation—acute angle-closure glaucoma causes permanent vision loss within hours if untreated, with 18% of affected eyes becoming blind 1
• Do not use opioids or butalbital-containing compounds—these lead to dependency and medication-overuse headache 5
• Do not repeat triptan treatment multiple times in 48 hours—while allowed for relapses, this increases medication-overuse headache risk 2