What is the onset time for sublingual nitroglycerin when used for angina?

What is the onset time for sublingual nitroglycerin when used for angina?

• A. 30 seconds
• B. 5-10 minutes
• C. 1-3 minutes
• D. 15-20 minutes

Answer: (C)

Sublingual nitroglycerin works quickly because it’s absorbed directly through the mouth’s mucous membrane, bypassing the liver. This rapid absorption delivers the drug to the heart and vascular system within a few minutes, so angina relief typically begins in about 1 to 3 minutes after you place it under the tongue. That near-immediate onset is why it’s used for acute angina attacks and can be repeated at 5-minute intervals if pain persists (up to three doses). The other timeframes are inconsistent with how fast sublingual nitro acts, since it’s faster than 15–20 minutes and not usually as slow as 5–10 minutes, but not instantaneous like 30 seconds.

Sublingual nitroglycerin works quickly because it’s absorbed directly through the mouth’s mucous membrane, bypassing the liver. This rapid absorption delivers the drug to the heart and vascular system within a few minutes, so angina relief typically begins in about 1 to 3 minutes after you place it under the tongue. That near-immediate onset is why it’s used for acute angina attacks and can be repeated at 5-minute intervals if pain persists (up to three doses). The other timeframes are inconsistent with how fast sublingual nitro acts, since it’s faster than 15–20 minutes and not usually as slow as 5–10 minutes, but not instantaneous like 30 seconds.