A 67-year-old woman is initiated on glyceryl trinitrate 400micrograms spray for the treatment of acute angina. She takes aspirin, atorvastatin, bisoprolol, clopidogrel and ramipril. Which statement is the most appropriate advice regarding use of the spray?

• A. Spray directly under the tongue and close mouth immediately after use
• B. Spray directly under the tongue and keep mouth open for 5 minutes
• C. Rinse mouth after using the spray
• D. Do not use spray if you have taken aspirin

Answer: (A)

Glyceryl trinitrate (nitroglycerin) given as a spray works best when absorbed directly through the sublingual mucosa. That rapid absorption is achieved if the spray is placed under the tongue and the mouth is kept closed so the medicine isn’t washed away by saliva or swallowed too soon. Rinsing the mouth or keeping it open would dilute or remove the drug and delay its action. There is no need to avoid aspirin: nitrates are commonly used with antiplatelet therapy in angina. So the best advice is to spray under the tongue and keep the mouth closed after use, allowing the spray to dissolve and be absorbed quickly. If chest pain persists after one spray, seek urgent care and follow local guidelines for repeat dosing.