Isosorbide dinitrate is an organic nitrate that is converted to nitric oxide (NO), causing venous and arterial vasodilation, reducing cardiac preload and afterload.
Also known as: Isordil, Dilatrate
Nitrate + PDE5 inhibitor: CONTRAINDICATED — potentially fatal severe hypotension.
Both cause potent vasodilation. The combination can cause severe and potentially fatal hypotension. CONTRAINDICATED — minimum 24-hour interval.
DailyMed/FDA (NIH/NLM) — approved Isosorbide Dinitrate label: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=44ede034-1fa1-4993-9aa5-49e04fada541
Nitrate + PDE5 inhibitor: CONTRAINDICATED — potentially fatal severe hypotension.
Isosorbide is converted to NO, which activates guanylate cyclase and raises cGMP. Sildenafil inhibits PDE5, which degrades cGMP. The combination results in massive cGMP accumulation, causing extreme vasodilation and severe hypotension (systolic BP <70 mmHg). This combination has caused documented deaths. Safety interval is minimum 24 hours for sildenafil (half-life 4h) or 48 hours for tadalafil (half-life 17.5h). CONTRAINDICATED under any circumstances.
Nitrate + PDE5 inhibitor: CONTRAINDICATED. Potentially fatal severe hypotension. Minimum 24-hour (sildenafil) or 48-hour (tadalafil) interval between drugs.
Both cause potent vasodilation. The combination can cause severe and potentially fatal hypotension. CONTRAINDICATED — minimum 24-hour interval.
DailyMed/FDA (NIH/NLM) — approved Isosorbide Dinitrate label: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=44ede034-1fa1-4993-9aa5-49e04fada541
Alcohol potentiates the hypotensive effect of isosorbide.
Avoid or limit alcohol consumption during treatment.
DailyMed/FDA (NIH/NLM) — approved Isosorbide Dinitrate label: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=44ede034-1fa1-4993-9aa5-49e04fada541
May cause severe hypotension. Use with caution in severe heart failure.
Start at low dose and titrate slowly.
DailyMed/FDA (NIH/NLM) — approved Isosorbide Dinitrate label: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=44ede034-1fa1-4993-9aa5-49e04fada541
Use only if benefit justifies risk. May cause maternal hypotension.
Use with caution in any trimester.
Unknown if excreted in breast milk. Prefer alternatives.
Use minimum effective dose. Monitor blood pressure.
DailyMed/FDA (NIH/NLM) — approved Isosorbide Dinitrate label: https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=44ede034-1fa1-4993-9aa5-49e04fada541
Clinical and educational support tool. The information does not replace a medical prescription or the opinion of a qualified healthcare professional.
Organic nitrate that is converted to nitric oxide (NO) in vascular smooth muscle, activating guanylate cyclase and raising cGMP, causing vasodilation.
Is converted to nitric oxide (NO) by vascular smooth muscle. NO activates soluble guanylate cyclase, raising intracellular cGMP and causing smooth muscle relaxation.
Oral bioavailability: 25-50% (extensive first-pass effect). Should be administered on an empty stomach for maximum absorption. Tmax: 15-30 minutes (sublingual).
Hepatically metabolised (dehydrogenase). Tolerance with continuous use (sulphydryl group depletion). No CYP-mediated interactions.
1 hour (oral); minutes (sublingual). Elimination: urine (glucuronide metabolites).
Medicines from the same therapeutic group (ATC classification) or the same pharmacological class.
