How should nitroglycerin be tapered safely in a patient on chronic angina therapy (oral sustained‑release, transdermal patch, or intravenous infusion)?

How to Taper Nitroglycerin

When discontinuing chronic nitroglycerin therapy (IV, transdermal, or oral sustained-release), gradually reduce the dose over 12-24 hours while monitoring for rebound ischemia, rather than abrupt cessation.

Tapering Strategy by Formulation

Intravenous Nitroglycerin

• Reduce IV nitroglycerin by 10-20 mcg/min decrements every 3-5 hours once the patient has been symptom-free for 12-24 hours 1
• Transition to oral or topical nitrates before complete discontinuation to prevent rebound ischemia 1
• Monitor blood pressure and heart rate closely during down-titration, as tolerance may have developed and withdrawal can unmask underlying hemodynamic instability 2

Transdermal Patches

• Remove patches gradually by shortening application time rather than abrupt discontinuation 3, 4
• If using continuous 24-hour application, first transition to intermittent dosing (12-14 hours on, 10-12 hours off) for several days before complete cessation 4, 5
• For patients already on intermittent therapy, reduce patch strength by 50% for 2-3 days, then discontinue 3

Oral Sustained-Release Preparations

• Reduce the dose by 50% for 2-3 days, then discontinue 6
• Alternatively, increase the nitrate-free interval progressively (from 10-12 hours to 16-18 hours) before stopping 6
• Maintain sublingual nitroglycerin availability for breakthrough symptoms during tapering 7

Critical Monitoring During Tapering

Watch for Rebound Phenomena

• A small percentage of patients experience increased anginal frequency during the nitrate-free interval or after discontinuation 7, 8
• Rebound is more clinically relevant in patients with frequent or nocturnal angina who were on continuous therapy 8
• If rebound occurs, slow the taper and consider maintaining a low-dose intermittent regimen 8

Hemodynamic Monitoring

• Check blood pressure and heart rate before each dose reduction 2
• Avoid tapering in patients with active ischemic symptoms, as this is not the appropriate time for discontinuation 2
• Be especially cautious in patients with inferior wall MI or right ventricular involvement, as they are preload-dependent and may decompensate 2

Common Pitfalls to Avoid

• Never abruptly discontinue IV nitroglycerin in patients who have been on high doses (>100 mcg/min) for >24 hours, as tolerance development means sudden withdrawal can precipitate rebound ischemia 1, 8
• Do not taper if the patient is hypotensive (systolic BP <90 mmHg) or has developed marked bradycardia or tachycardia, as these indicate hemodynamic instability requiring different management 2, 1
• Avoid tapering during acute ischemic episodes—stabilize the patient first, then consider tapering when symptom-free 2

Special Considerations

Tolerance Context

• Patients on continuous therapy for >24 hours have developed tolerance, meaning they may have reduced nitrate responsiveness even to sublingual doses 6, 1, 7
• The nitrate-free interval during tapering helps restore nitrate sensitivity 6, 4
• Tolerance is less problematic with intermittent regimens, making tapering simpler in these patients 8, 5

Transition Strategy

• Use non-tolerance-producing regimens (lower doses with intermittent dosing) when transitioning from IV to oral/topical forms 1
• Overlap the new formulation with the old for 12-24 hours before beginning the taper of the original formulation 1
• Ensure beta-blockers or calcium channel blockers are optimized before nitrate discontinuation if the patient requires ongoing anti-anginal therapy 5