Acetylsalicylic acid × Dexamethasone

Additive ulcerogenic effect. Dexamethasone suppresses GI mucosal repair; aspirin blocks protective prostaglandins.

Epigastric pain, nausea, heartburn. With prolonged therapy: peptic ulcer and GI bleeding risk (black stools, vomiting blood or coffee-ground material). Older patients and prior peptic ulcer disease: higher risk.

Aspirin SmPCs, including those for 100 mg tablets, advise against combining aspirin with systemic glucocorticoids because together they raise the risk of ulcers and gastrointestinal bleeding (aspirin 100 mg and 500 mg SmPCs). The exception is hydrocortisone used as replacement therapy in Addison's disease. If the combination cannot be avoided, use it with caution: tell the patient in advance about the signs of bleeding (black stools, vomiting blood, marked weakness, low blood pressure, cold sweat, abdominal pain, dizziness) and that if they appear, aspirin is stopped and they must see a doctor at once (aspirin SmPCs). In patients with peptic ulcer disease, give an anti-ulcer drug together with dexamethasone (dexamethasone SmPC). Corticosteroids can increase salicylate clearance, and in hypoprothrombinaemia the patient is monitored for aspirin toxicity on this combination (US dexamethasone label).