Which route provides rapid onset for nitroglycerin?

• A. Transdermal patch
• B. Sublingual
• C. Oral tablet
• D. Intravenous infusion

Answer: (B)

The fastest way nitroglycerin reaches the bloodstream is through the sublingual route. Placing the tablet under the tongue lets it be absorbed directly into the highly vascular tissue there, bypassing the liver (no first-pass metabolism). This causes a rapid rise in plasma levels and quick relief from angina, typically within 1–3 minutes, with effects lasting about 30–60 minutes. Transdermal patches deliver the drug slowly over hours, so they’re not for rapid relief. Oral tablets must travel through the digestive system and are also subjected to liver metabolism, leading to slower and more variable onset. Intravenous administration acts quickly too, but it’s used in hospital settings and isn’t the typical option for self-administered rapid relief; for quick home-use relief, sublingual is the best choice.