What is the route and dosage of nitroglycerin in this protocol?

• A. 0.4 mg intravenous
• B. 0.4 mg transdermal
• C. 0.4 mg oral
• D. 0.4 mg sublingual

Answer: (D)

Nitroglycerin for acute chest pain is given sublingually at a small, fast-acting dose because this route provides rapid absorption directly into the bloodstream, bypassing the stomach and liver. That quick uptake lets the medication start reducing workload on the heart within minutes, which is essential in an EMS setting. The standard sublingual dose is 0.4 mg per administration, with repeat doses as allowed by the protocol if the patient remains symptomatic and blood pressure stays adequate.

Other routes don’t fit as well in this scenario: intravenous dosing isn’t a fixed 0.4 mg dose and is used with controlled infusions, transdermal patches deliver a slower, continuous amount rather than a rapid effect, and oral nitroglycerin has poor bioavailability because much is lost to first-pass metabolism. So sublingual 0.4 mg best matches the needs of rapid, controllable relief in the protocol.