Do not use if allergic to salicylates/aspirin, lidocaine or other local anaesthetics. Use with caution in children, in patients with bleeding disorders, asthma sensitive to NSAIDs, or if taking blood thinners. Avoid contact with eyes; do not swallow large amounts. Stop and seek medical advice if ulcers persist >7 days, are recurrent, or if severe swelling, breathing difficulty or widespread rash occurs.