isosorbide mononitrate vs nitroglycerin

PlainMeds reviewed this comparison against our methodology in August 2026. It places FDA and CMS record fields side by side, without recommending either medication.

Side-by-side comparison of isosorbide mononitrate and nitroglycerin. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

Drug Class
isosorbide mononitrate Nitrate Vasodilator
nitroglycerin Nitrate Vasodilator
Type
isosorbide mononitrate Prescription
nitroglycerin Prescription
Summary
isosorbide mononitrate

Isosorbide mononitrate is a medicine that helps prevent chest pain. It relaxes your blood vessels, so your heart doesn't have to work as hard.

nitroglycerin

Nitroglycerin sublingual tablets help to relieve chest pain (angina) due to heart disease. They work by widening blood vessels to improve blood flow.

What It Treats
isosorbide mononitrate

This medicine is used to prevent angina, a type of chest pain. Angina is caused by heart disease. This medicine will not help if you are having chest pain right now.

nitroglycerin

This medicine treats chest pain called angina. Angina is caused by heart disease. Nitroglycerin can relieve an attack or prevent angina before activities that may cause it.

How It Works
isosorbide mononitrate

Isosorbide mononitrate is a nitrate. It works by relaxing the muscles in your blood vessels. This allows more blood and oxygen to flow to your heart while reducing its workload.

nitroglycerin

Nitroglycerin is a nitrate vasodilator. It widens your blood vessels. This lets more blood flow to your heart and reduces chest pain.

Common Side Effects
isosorbide mononitrate
  • Headache
  • Dizziness
nitroglycerin
  • Headache
  • Dizziness
  • Tingling
FAERS Reports
isosorbide mononitrate
  • Dyspnoea 1,503
  • Dizziness 1,397
  • Diarrhoea 1,249
  • Fatigue 1,243
  • Nausea 1,231
nitroglycerin
  • Dyspnoea 4,151
  • Pain 3,626
  • Fatigue 3,491
  • Myocardial Infarction 3,393
  • Nausea 3,266
Serious Warnings
isosorbide mononitrate

You should not take this medicine if you are allergic to nitrates or nitrites.

nitroglycerin

Taking too much nitroglycerin can lead to tolerance, where the drug stops working as well. Nitroglycerin can also cause very low blood pressure, especially if you stand up quickly. If chest pain continues after 3 tablets, get medical help right away.

Pregnancy
isosorbide mononitrate

It is not known if this medicine will harm an unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. It is also not known if this medicine passes into breast milk. Talk to your doctor if you are breastfeeding.

nitroglycerin

It is not known if nitroglycerin will harm an unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. It is also not known if nitroglycerin passes into breast milk. Talk to your doctor if you are breastfeeding.

Also Compare, Nearby Drugs

Compare isosorbide mononitrate with

Compare nitroglycerin with

How to Read This isosorbide mononitrate vs nitroglycerin Comparison

isosorbide mononitrate is classified in the Nitrate Vasodilator drug class, while nitroglycerin sits within the Nitrate Vasodilator class. Because both drugs share the same classification, they are often considered interchangeable in theory, but clinical outcomes rarely track that cleanly. Both drugs are prescription-only, so a licensed provider must authorize use.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, isosorbide mononitrate has 6,623 submissions while nitroglycerin has 17,927. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. No direct interaction between these two drugs is listed in our FDA-derived dataset, though co-prescription still warrants pharmacist review. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for isosorbide mononitrate or nitroglycerin.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.