Mouth Blisters (Oral Vesicles/Ulcers): Home Care, Red Flags, and When to See a Professional

Oral blisters (vesicles, bullae) or ulcers (canker sores, herpetic lesions) are common. Most heal in 7–14 days. Proper care speeds healing and prevents complications.

Immediate Self-Care

1. Don't pop or bite. Intact blister roof = biological dressing. Rupture → pain, infection risk, delayed healing.
2. Oral hygiene: Soft brush, SLS-free toothpaste. Rinse with saline (½ tsp salt in 8 oz warm water) or alcohol-free chlorhexidine 0.12% every 4–6 hours.
3. Pain control: Topical benzocaine 20% / lidocaine 2% / hydroxypropyl cellulose (Orabase) — apply before meals. Systemic: ibuprofen 400–600 mg q6h or acetaminophen 1g q6h.
4. Cold therapy: Ice chips, cold water, or ice pack externally (10 min on/off) — vasoconstriction, analgesia.
5. Diet: Cool, soft, bland (yogurt, smoothies, mashed potatoes). Avoid: acidic (citrus, tomato), spicy, salty, crunchy, hot, alcohol, tobacco.
6. Hydration: Sip water constantly. Straw bypasses sore areas.
7. Protect: Orthodontic wax on sharp teeth/appliances. Orabase paste as barrier.

Common Causes

• Minor trauma: Biting, sharp food, dental work.
• Aphthous ulcers (canker sores): Stress, trauma, SLS, nutritional deficiency (B12, Fe, folate), immune.
• Herpes simplex (HSV-1): Prodrome (tingle) → clustered vesicles → ulcers. Recurrent.
• Hand-foot-mouth (Coxsackie), herpangina.
• Autoimmune: Lichen planus, pemphigus, mucous membrane pemphigoid.
• Drug reactions: Stevens-Johnson/TEN (emergency).

Red Flags: See Dentist/Doctor Within 24–48h

• Lesion >2 weeks without improvement.
• Large (>1 cm), spreading, or multiple new lesions.
• Severe pain uncontrolled by OTC.
• Fever, dysphagia, drooling, trismus.
• Immunocompromised (chemo, HIV, steroids).
• Suspicious features: indurated, fixed, non-healing, unilateral — rule out malignancy.

Most oral blisters are benign and self-limited. Gentle care + time = resolution. Persistent or atypical lesions need biopsy.