Garlic is considered a valuable herbal medicine and has been used for centuries for treatment of various ailments. Along with its benefits comes some adverse effects. The present case describes chemical burn of oral mucosa caused by crushed garlic. To relieve toothache, the patient placed crushed garlic cloves in the buccal vestibule overnight and developed garlic burn injury manifesting as slough and ulceration in that region. Diagnosis was made on the basis of definitive history elicited from the patient. Topical anesthetic and antibacterial agents were advised for local application, and systemic analgesic was prescribed. The patient was referred to the Department of Endodontics for further treatment of the toothache. Garlic burn should be considered in the differential diagnosis for chemical burn if the burn is not found to be associated with other common factors, and history taking should include questions regarding use of herbal products, home remedies, and alternative medicine. Possible adverse effects of these methods should be considered. Palabras clave: chemical burn, garlic, garlic burn, self-inflicted injury