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Nitrates and sildenafil — GPhC CRA MCQ

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HardCardiovascular TherapeuticsNitrates and sildenafilGPhC CRA

A 58-year-old man asks to buy sildenafil. He takes modified-release isosorbide mononitrate every morning and carries glyceryl trinitrate spray, although he has not used the spray for two weeks. Blood pressure is 132/78 mmHg and he has no current chest pain. What is the most appropriate action?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: B — Decline supply and arrange prescriber review

Sildenafil is contraindicated in a patient who uses nitrate treatment for angina because PDE5 inhibition can markedly augment nitrate-mediated vasodilation and cause dangerous hypotension. The contraindication is not removed by recent non-use of rescue GTN or by a self-directed interruption of long-acting nitrate therapy. Tadalafil has the same clinically important class interaction. Supply should be declined and the patient referred for review of erectile dysfunction and anti-anginal treatment.

Reference: NHS: Who can and cannot take sildenafil: https://www.nhs.uk/medicines/sildenafil-viagra/who-can-and-cannot-take-sildenafil/