Indications
Nitroglycerin relieves chest pain from angina and suspected myocardial infarction by dilating vessels and lowering preload. The usual dose is 0.4 mg sublingual every 3 to 5 minutes up to three doses. Always verify that the patient has a prescription or that medical direction approves.
Contraindications
Do not give nitroglycerin if systolic blood pressure is below 90 to 100 mmHg, or if the patient has taken sildenafil or tadalafil within 24 to 48 hours. Inferior wall MI with right ventricular involvement is also a concern because those patients depend on preload. Perform a 12-lead and consider right-sided leads when appropriate.
Administration Tips
Have the patient sit, check blood pressure before and after each dose, and warn them about headache and lightheadedness. Wear gloves or avoid touching the tablet directly. Reassess pain and vital signs after every dose.