Isosorbide dinitrate
ISORDIL
What it isNitric oxide donor; angina, and with hydralazine in heart failure.
Why this oneThe hydralazine combination has mortality benefit in Black patients with HFrEF, and it is usable when renal function forbids an ACE inhibitor.
What limits itExtensive first-pass metabolism means three-times-daily dosing and a mandatory nitrate-free interval. Fatal hypotension with PDE5 inhibitors.
FDA-approved for
- angina pectoris
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Prevention of angina pectoris | Adult | 5-20 mg BID-TID | 10-40 mg BID-TID |
Renal Undefined
Hepatic Undefined
No regimen provides more than ~12 hours of continuous anti-anginal effect per day.
Instructions
- Provide a daily nitrate-free interval of at least 14 hours to minimize tolerance
- Use the minimum dose that produces the desired effect
Contraindications
- Concurrent PDE5 inhibitors (sildenafil, tadalafil, vardenafil) — severe hypotension/syncope
- Concurrent riociguat (soluble guanylate cyclase stimulator) — hypotension
Cautions
- Severe/recurrent headache
- Symptomatic hypotension, lightheadedness, syncope
- Tolerance with continuous (no interval) dosing
- Rare methemoglobinemia
Adverse reactions
- Headache (most common)
- Lightheadedness
- Hypotension
- Syncope, crescendo angina, rebound hypertension (uncommon)
- Methemoglobinemia (extremely rare)
Pregnancy Category C; use only if potential benefit justifies fetal risk.
Lactation Undefined
NO BOXED WARNINGS
Principal riskFatal hypotension with PDE5 inhibitors
Cost, est. cash$5–$150/month
Generic entry1986
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.
Mechanism of action: Isosorbide dinitrate ballicule
Open Isosorbide dinitrate in the interactive console ↗
Memory aids: mascots and interaction avatars
two nitrates to contrast with isosorbide and isosorbide mononitrate