What is the recommended dose and frequency of Nitroglycerin (glyceryl trinitrate)?

From the Guidelines

Nitroglycerin should be administered at a starting dose of 0.3-0.4 mg sublingually for acute angina episodes, which can be repeated every 5 minutes for up to 3 doses if chest pain persists, as recommended by the most recent guidelines 1.

Key Considerations

• The dose and frequency of nitroglycerin administration may vary depending on the patient's response and the severity of their symptoms.
• Patients should be instructed to sit or lie down when taking nitroglycerin to avoid dizziness or fainting due to a sudden drop in blood pressure.
• Headache is a common side effect of nitroglycerin, indicating that the medication is working by dilating blood vessels.
• Nitroglycerin works by releasing nitric oxide, which relaxes vascular smooth muscle, dilating blood vessels and improving blood flow to the heart while reducing its workload.

Administration Routes and Dosages

• Sublingual tablets: 0.3 to 0.6 mg up to 1.5 mg, with a duration of effect of 1 to 7 minutes 1.
• Spray: 0.4 mg as needed, with a similar duration of effect to sublingual tablets 1.
• Transdermal: 0.2 to 0.8 mg per hour every 12 hours, with a duration of effect of 8 to 12 hours during intermittent therapy 1.
• Intravenous: 5 to 200 mcg per minute, with tolerance developing in 7 to 8 hours 1.

Important Precautions

• Nitrates should not be administered to patients with hypotension or to those who have received a phosphodiesterase inhibitor within a certain time frame (e.g., 24 hours for sildenafil or vardenafil, or 48 hours for tadalafil) 1.
• Patients with right ventricular infarction should be administered nitrates with caution 1.

From the FDA Drug Label

DOSAGE & ADMINISTRATION One tablet should be dissolved under the tongue or in the buccal pouch at the first sign of an acute anginal attack. The dose may be repeated approximately every 5 minutes until relief is obtained. If the pain persists after a total of 3 tablets in a 15-minute period, or if the pain is different than is typically experienced, prompt medical attention is recommended. The recommended dose of nitroglycerin is one tablet, and the recommended frequency is approximately every 5 minutes, up to a total of 3 tablets in a 15-minute period 2.

• The dose may be repeated as needed for relief of anginal symptoms.
• The patient should rest, preferably in the sitting position, during administration.

From the Research

Nitroglycerin Dose and Frequency

• The optimal dose and frequency of nitroglycerin administration can vary depending on the specific clinical context and patient population 3, 4.
• In patients with acute myocardial infarction, intravenous nitroglycerin can be administered at infusion rates of less than 30 micrograms/min, which acts principally as a venodilator, while higher infusion rates can produce a balanced venous and arterial dilating effect 3.
• The frequency of nitroglycerin administration can range from short-term infusions (e.g., 24-48 hours) to longer-term therapy, depending on the patient's clinical status and response to treatment 3, 5.
• In patients with stable angina, nitroglycerin can be administered as needed to relieve angina symptoms, with the goal of improving quality of life and reducing the risk of cardiovascular events 6.
• The development of nitroglycerin tolerance can limit the effectiveness of this therapy, and strategies to prevent or mitigate tolerance, such as coadministration of ALDH2 activators, are being explored 4.

Clinical Considerations

• Nitroglycerin can have significant effects on platelet aggregation, which can be beneficial in patients with acute coronary syndrome, but may also increase the risk of bleeding complications 7.
• The use of nitroglycerin in combination with other antianginal therapies, such as beta-blockers and calcium channel blockers, can be effective in managing angina symptoms and improving patient outcomes 5, 6.
• The choice of nitroglycerin dose and frequency should be individualized based on the patient's clinical status, response to treatment, and potential side effects or interactions with other medications 3, 4, 5, 7, 6.