Loss of Smell After a Cold: Recovery Timeline and Interventions

Post-viral olfactory dysfunction (PVOD) is common after URI (including COVID-19).

• Recovery: 60–80% recover within 2–4 weeks; 90% by 6 months. Some take 1–2 years.
• Persistent (>1 year): ~5–10%; may be permanent if olfactory epithelium replaced by respiratory epithelium.

Interventions

• Olfactory training (gold standard): Sniff 4 essential oils (rose, lemon, clove, eucalyptus) 2×/day for ≥12 weeks. Stimulates neuroplasticity.
• Intranasal corticosteroids: If inflammatory component (e.g., chronic rhinosinusitis); limited evidence for pure PVOD.
• Oral corticosteroids: Short course sometimes used early; risks vs. benefits.
• Supplements: Vitamin A, omega-3, zinc — limited data.
• Alpha-lipoic acid, theophylline: Investigational.

See ENT if no improvement at 4–6 weeks. Endoscopy rules out polyps, tumors, structural issues. MRI if neurologic signs.