Pill box

Published on Monday 4 April 2005 01:19

THIS week under the microscope is Glyceryl trinitrate (GTN) used to treat Angina.

Generic name: Glyceryl trinitrate (GTN)

Brand names: Coro-Nitro, Nitromin, Suscard, Sustac, Nitrocine, Nitronal, Deponit, Minitran, Nitro-Dur, Percutol, Trintek

Type of drug: Nitrate

Used to treat: Angina - chest pain or tightness due to poor blood supply to the heart. Also used for the prevention of angina.

Notes: Nitrates increase the blood and oxygen supply to the heart by relaxing blood vessels. This reduces the necessary work of the heart muscle and prevents strain, thereby relieving associated pain and lowering the risk of angina.

Dosage: Administered through dissolve-in-the-mouth tablets, aerosol spray under the tongue, patches, injection or ointment.

Side-effects and warnings: Throbbing headache, hot flushes, dizziness, drop in blood pressure upon standing, rapid heart beat. Injection form may cause nausea, muscle twitching, palpitations, fainting, abdominal pain, retching, low blood pressure, excessive sweating and restlessness. Prolonged use has been associated with methemoglobinaemia - the presence in red blood cells of metheglobin, a form of hemoglobin unable to carry oxygen.