Table 1.

Pharmacological strategies for VSA management.

Class of drugs	Mechanisms of action	Drugs		Dosage	Special recommendations
CCBs	↓ Spontaneous and inducible coronary spasm via vascular smooth muscle relaxation ↓ O2 demand	Non-dihydropyridine	Verapamil	240 mg SR (single or divided doses) daily	In severe VSA consider high dosages of CCBs (2 × 200 mg diltiazem daily) or a combination of both non-dihydropyridine with dihydropyridine CCBs
			Diltiazem	90 mg twice daily or 120–360 mg (single or divided doses)
		Dihydropyridine	Nifedipine	5 mg 3 times/day
				SR: 10 mg twice/day (up to 30 mg/day)
			Amlodipine	5–10 mg once a day
Nitrates	↓ Spontaneous and inducible coronary spasm via large epicardial vasodilation ↓ O2 demand	Short-acting nitrates	Glyceryl trinitrate	300 µg if needed	Efficacy of short-acting nitrates might vary, and repeated administration is often needed
			Isosorbide mononitrate XL	30 mg daily
			Isosorbide dinitrate	30–120 mg daily
		Long-acting nitrates	Isosorbide mononitrate SR	25 mg to a maximum of 120 mg daily
			Isosorbide dinitrate SR	40 mg once daily
Potassium channel activator	Coronary microvascular dilatory effect	Nicorandil		10–20 mg once daily	Consider patients experiencing VSA and still symptomatic despite CCBs followed by nitrates

CCBs, calcium-channel blockers; SR, slow release; VSA, vasospastic angina.