1. Hypotension = Serious side effect
2. Hypertrophic obstructive cardiomyopathy = contraindicated but not due to nitrate
3. Headache = most common side effect - unpleasant, but not serious
4. Glaucoma = (closed angle glaucoma) worsened by nitrates but not due to nitrate
Hypotension induced by nitrates may be accompanied by paradoxical bradycardia and increased angina. Severe postural hypotension with light-headedness and dizziness is frequently observed after the consumption of alcohol while taking nitrates.
I am not happy with this answer but don't have the choice so I would go with it. Because we know that nitrates causes vasodilation & hence hypotension but its not that serious very very rare unless there is preexisting conditions like patient on antihypertensive drugs or have consume alcohol etc.
Anyway lets wait see the explanation
