Last updated: June 4, 2021

Summarytoggle arrow icon

Nitrates are a class of medications that increase the release of nitric oxide (NO) in vascular smooth muscle cells, leading to smooth muscle relaxation and subsequent vasodilation. Veins are affected more than arteries, and most therapeutic effects of nitrates result from venous pooling and subsequently decreased preload. Rapid- and short-acting nitrates are primarily used in the symptomatic treatment of acute angina pectoris and hypertensive urgency. Side effects may include headache (nitrate-induced headache), gastroesophageal reflux, and hypotension with syncope. Prior intake of PDE-5 inhibitors significantly increases the risk of hypotension.

Agents and dosagestoggle arrow icon

Overview of pharmacokinetics of nitrates
Agents Formulations Long- vs. short-acting Onset of action Duration of action
  • Oral
  • Sublingual
  • Short
  • 2–5 minutes
  • 15–30 minutes
  • Transdermal patch
  • Long
  • 30 minutes
  • 8–14 hours

Isosorbide dinitrate

  • Sublingual
  • Short
  • 2–5 minutes
  • 1–2 hours
  • Oral
  • Long
  • 1 hour
  • 4-6 hours
Isosorbide mononitrate
  • Oral
  • Long
  • 30–45 minutes
  • 6–24 hours
Sodium nitroprusside
  • Intravenous
  • Short
  • Immediate
  • Lasts during infusion and within 1–10 minutes after its discontinuation


The authors cannot be held responsible for the contents provided being exhaustive, correct, or up to date. The contents have been meticulously researched by our editors. Especially updates regarding warnings and recommendations must be considered. Unless otherwise noted, the recommendations provided apply to adults.

Pharmacodynamicstoggle arrow icon


Adverse effectstoggle arrow icon

We list the most important adverse effects. The selection is not exhaustive.

Indicationstoggle arrow icon


Contraindicationstoggle arrow icon


We list the most important contraindications. The selection is not exhaustive.

Referencestoggle arrow icon

  1. Katzung B,Trevor A. Basic and Clinical Pharmacology. McGraw-Hill Education ; 2014
  2. Kannam JP, Gersh BJ. Nitrates in the management of stable angina pectoris. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. Last updated: June 12, 2015. Accessed: April 5, 2017.
  3. Nitrates. . Accessed: May 25, 2018.
  4. Kaufman MS, Ganti L, Rusovici A. First Aid for the Medicine Clerkship. McGraw-Hill Companies ; 2010

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