How Nitroglycerin Works
Nitroglycerin is a vasodilator that reduces preload and cardiac workload, which can relieve chest pain from angina. The usual dose is 0.4 mg sublingually, repeated every 3 to 5 minutes up to three doses if the blood pressure remains adequate.
Contraindications
Do not give nitroglycerin to patients who are hypotensive, with a systolic blood pressure below 100 mmHg or lower according to protocol. Avoid it if the patient has used erectile dysfunction medications such as sildenafil or tadalafil within the past 24 to 48 hours, or in cases of right ventricular infarction.
Administration Tips
Have the patient sit, check blood pressure before and after each dose, and ask about headaches or dizziness. Make sure the patient is not already at the maximum dose. If the pain remains, continue to treat as acute coronary syndrome and provide rapid transport.