Context
This table presents, in a pragmatic way, the pharmacological classes used in stable angina, with examples, therapeutic line, contraindications and clinical notes on use. The logic is simple: use first-line drugs for baseline symptom control, sublingual nitrates for rescue treatment, and add second-line drugs when control is insufficient or limited by comorbidities.
Short-acting nitrates
We start with short-acting nitrates, intended for immediate relief of an angina episode and anticipatory prophylaxis before exertion. Usual examples are sublingual nitroglycerin and sublingual isosorbide dinitrate. The major contraindication is concomitant use with phosphodiesterase-5 inhibitors, which is absolute; marked hypotension and obstructive hypertrophic cardiomyopathy should also be considered. The table reinforces correct use: typical response within about five minutes, repetition every five minutes up to three doses in total, and urgent medical care if there is no relief. For predictable exertion, administer five to ten minutes beforehand.
Long-acting nitrates
Long-acting nitrates — transdermal nitroglycerin, isosorbide dinitrate or isosorbide mononitrate — are used as add-on/second-line treatment to reduce episodes. They have the same contraindications as short-acting nitrates and require a daily nitrate-free interval of 10–12 hours to minimise tolerance, with practical instructions on application and site rotation.
Beta-blockers
Among first-line drugs, beta-blockers are a cornerstone: atenolol, bisoprolol, metoprolol, nebivolol, carvedilol and propranolol. The aim is to reduce heart rate and myocardial oxygen demand. They are contraindicated in marked bradycardia, second- or third-degree AV block without a pacemaker, uncontrolled asthma/active bronchospasm and acute heart failure. A typical practical target is resting HR 55–60 bpm, with titration over 2–4 weeks and avoidance of abrupt withdrawal.
Calcium-channel blockers
Calcium-channel blockers are divided into dihydropyridines — amlodipine, felodipine, prolonged-release nicardipine — and non-dihydropyridines — verapamil and diltiazem. Both may be used as first-line treatment. Dihydropyridines are preferred in bradycardia or AV conduction abnormalities, should be used with caution in severe aortic stenosis and ideally as prolonged-release formulations; immediate-release nifedipine should be avoided in stable angina. Non-dihydropyridines reduce heart rate and conduction; they are contraindicated in heart failure with reduced LVEF, bradycardia and AV block, and should not be combined with beta-blockers or ivabradine because of the risk of conduction disturbances, especially in older patients.
Second-line treatment / add-ons
When control remains insufficient, second-line treatment or add-on therapy is used. Ivabradine is an option in sinus rhythm with HR ≥ 70 bpm; it should be avoided in sick sinus syndrome and AV block ≥ 2 without a pacemaker, with monitoring for bradycardia and atrial fibrillation. Ranolazine improves symptoms without reducing HR or BP; QT monitoring is required and it should be avoided with potent CYP3A4 inhibitors, in moderate/severe hepatic impairment or CrCl < 30 ml/min. Nicorandil is an add-on alternative, with attention to mucosal ulceration and hypotension, and should not be combined with PDE5 inhibitors.
