Brief Answer: Usually due to minor infections. Detailed Answer: Hello, Thanks for trusting us with your health concern. mouth ulcers usually resolve with good fluid intake, good oral hygiene and gentle debridement of the mouth. Use chlorhexidine mouth wash and avoid acid drinks, like fruit juices or fizzy drinks, or drink them through a straw so they don't irritate your mouth. Also avoid spicy food and sharp food and citrus fruits. You can use topical ointments like numbing ointments, such as benzocaine (Oragel), anti-inflammatory (steroid) gels, benadryl allergy liquid mouthwash, oral preparations of steroids and vitamin supplement. Oral pain killers like Ibuprofen also help. But all these medicines are available under prescription and should be taken under a doctor’s guidance. Please feel free to discuss further. I will be glad to answer the follow up queries that you have. Wishing you good health. Regards. Dr. Rakhi Tayal. For future query, you can directly approach me through my profile URL http://bit.ly/Dr-Rakhi-Tayal

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