Therapy

Why?

• Fewer patients have persistent angina requiring revascularisation, but severe headaches are common, and many patients stop therapy. ^a

Adding n-acetylcysteine to nitrates reduces persistent angina, but can cause severe headaches

Patient	Treatment	Comparison	Outcome	CER	RRR (95% CI)	NNT (95% CI)
unstable angina a	n-acetylcysteine and topical nitrate	topical nitrate	persistent angina requiring revascularisation at weeks	33%	67% (21% to 86%)	5 (3 to 17)
			severe headache at 4 months	4.4%	-610% (-2800% to -73%)	-4 (-8 to -2)
			treatment withdrawal at 4 months	8.7%	-280% (-930% to -37%)	-4 (-11 to -3)
refractory unstable angina b	n-acetylcysteine and iv nitrates	iv nitrates	myocardial infarction at 24 hours	46%	73% (13% to 91%)	3 (2 to 12)