Angina Management

Introduction to Nitrates and Nicorandil

All nitrates, including patches, must be used with a nitrate-free interval to avoid tolerance development, as recommended by the British Medical Journal guidelines 1

The American Heart Association/American College of Cardiology recommends a treatment algorithm for angina, starting with calcium channel blockers, followed by long-acting nitrates, and then nicorandil if necessary, according to the 2023 guidelines 2, 3
Nicorandil (5 mg BID, uptitrated) is specifically recommended for microvascular spasm by the American Heart Association/American College of Cardiology 2, 3

Topical nitroglycerin spray is recommended at a dose of 0.4 mg per spray as needed, with up to 3 doses administered at 3-5 minute intervals until pain is relieved or blood pressure limits its use, as recommended by the American College of Cardiology 4, 5
The standard dose is 0.4 mg per spray as needed, with a maximum recommended administration of up to 3 doses at 3-5 minute intervals 4, 5, 6
Transdermal patches should be applied in the morning and removed after 12-14 hours, with an initial dosing of 0.2-0.4 mg/hour (5-10 mg/24h) and a maximum recommended dose of 0.8 mg/hour (20 mg/24h) 7

Contraindications for nitrate use include hypotension (SBP <90 mm Hg or ≥30 mm Hg below baseline), extreme bradycardia or tachycardia, right ventricular infarction, and recent use of phosphodiesterase inhibitors, as stated by the American Heart Association guidelines 8
Common adverse effects of nitrates include headache, hypotension, dizziness, and flushing, with headache being the most common and typically resolving with continued use 7

To prevent tolerance, a daily nitrate-free period of 10-12 hours (typically overnight) is recommended, and switching from spray to transdermal patches with a nitrate-free interval is advised 7
When converting from intravenous to topical nitroglycerin, a gradual reduction in the intravenous dose is recommended to avoid rebound ischemia, and intermittent dosing regimens are superior to continuous therapy in maintaining anti-anginal efficacy 4, 7
Nitroglycerin spray should not be used at the expense of agents with proven mortality benefits such as β-blockers or ACE inhibitors in patients with acute coronary syndromes 4, 9