Angina bullosa hemorrhagica (ABH) is a very rare disorder of the subepithelium that is characterized by the sudden onset of a tense, blood-filled bulla on the oral mucosa. The bulla may expand rapidly over 1 or 2 days and then rupture, leaving behind an ulcer that heals within 7-10 days. More than one bulla may be present, and recurrences occur in around one-third of patients. The soft palate is most frequently affected, but ABH may arise on most other intraoral sites as well, including the tongue, buccal and lingual mucosa, and tonsillar fauces. Pharyngeal and esophageal cases have been reported. Rare reported sequelae include hoarseness and excessive blood-tinged salivation.

This condition affects men and women equally and typically occurs in adults aged 50-70 years. The pathophysiology of ABH is unclear. While precipitating factors such as hot drinks, inhaled corticosteroids, trauma from an adjacent sharp tooth edge, chewing, or a dental procedure have been reported, around half of patients have no obvious precipitant. Some of the reported cases in the literature have had concomitant hypertension and diabetes mellitus. A few patients with drug-induced or idiopathic thrombocytopenia have been reported to develop ABH-like bullae.