Isosorbide mononitrate
IMDUR
Pronunciation: eye-soe-SOR-bide mon-oe-NYE-trayt
“Endure monotonous Ice sorbet”
one nitrate to contrast with isosorbide and isosorbide dinitrate
What it isNitric-oxide donor causing venodilation; chronic angina prophylaxis.
Why this oneCompared with isosorbide dinitrate, predictable absorption and longer action simplify prophylaxis, but it cannot abort an acute attack.
What limits itPreserve a daily nitrate-free interval or tolerance develops. PDE5 inhibitors can cause fatal hypotension; headache commonly limits use.
FDA-approved for
- angina prophylaxis (~1991)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Prevention of angina pectoris due to coronary artery disease | Adults | 30 mg or 60 mg QAM | 120 mg QAM | 240 mg QD (rarely required) |
Titration Increase after several days.
Renal Undefined
Hepatic Undefined
Not for aborting an acute anginal episode (onset too slow). Headache is dose-related—start low for several days before increasing.
Instructions
- Take once daily in the morning on arising.
- Swallow whole with a half-glassful of fluid; do not chew or crush.
- 30 mg may be given as 1/2 of a scored 60 mg tablet.
Available strengths
- ER tab 30, 60, 120 mg
- tab 10, 20 mg
Contraindications
- Prior hypersensitivity or idiosyncratic reaction to other nitrates or nitrites
Cautions
- Severe hypotension with sildenafil (amplified vasodilation)
- Not recommended in acute MI or CHF (hypotension, tachycardia)
Adverse reactions
- Headache
- Dizziness
Cost
Generic entry1998
NO BOXED WARNINGS
Principal riskHypotension; fatal with PDE5 inhibitors
Classes and tags
Clinical profile
Legacy pregnancy categoryC
Defining liabilityGenerally tolerated at therapeutic doses; clinically important risks are agent-specific and increase with interactions or organ impairment.