Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concerns.. As per your complain ulcers on lips after stomach upset or acidity is due to eruption of apthous ulcers and occurs due to change in oral environment which is more towards acidic and causes ulceration.. Taking NSAID s can further increase acidity and gastric erosion, therefore you should avoid taking it and if taken, a protection against it in the form of taking Proton Pump Inhibitors like Pantoprazole, Omeprazole, Rabeprazole etc should be done.. As far as swelling of lips is concerned it can be probably due to allergic reaction, that can be due to allergy to any food or medication.. I would suggest you to consult an Allergist and get evaluated and a thorough clinical evaluation and investigations like blood investigation to rule out allergy and also consult a Gastroenterologist and get evaluated and an endoscopy to rule out for the cause of stomach upset can be ruled out.. As of now to relieve the ulcers you can gargle with numbing mouthwash containing Lignocaine.. You can also suck ice and do warm saline gargles.. Take a soft diet and avoid spicy food.. Take anti allergics like Levocetrizine for lip swelling and do cool compresses over the lips.. Hope this helps.. Regards.