Isosorbide Mononitrate

ATC code

C01DA14

Therapeutic class

Vasodilator used in cardiac diseases · Organic nitrate

Forms

oral tablet

Brand names

Mononitrato de Isosorbida Normon (ES) · Imdur (US) · Monoket (US) · Elantan (GB) · Monicor (FR)

Overall confidence

medium

Regulatory sources consulted

Approved indications

Prophylactic treatment of angina pectoris.

Contraindications

Absolute

Hypersensitivity to isosorbide mononitrate, other nitrates, or to any of the excipients.
Concomitant use of phosphodiesterase type 5 (PDE-5) inhibitors such as sildenafil, tadalafil, or vardenafil.
Concomitant use with riociguat, a soluble guanylate cyclase stimulator.
Severe hypotension (systolic blood pressure below 90 mmHg), cardiogenic shock, acute circulatory failure (shock, collapse).

Relative

Severe anemia, severe hypovolemia, hypertrophic obstructive cardiomyopathy, constrictive pericarditis, and cardiac tamponade.

Clinical warnings

Major warning · Nitrate headache: Very common, especially at the beginning of treatment. It usually disappears after a few days of continued treatment. — EMA SPC
Major warning · Tolerance: Continuous use without a nitrate-free interval can lead to the development of tolerance and cross-tolerance with other nitrates. — EMA SPC
Not suitable for the treatment of acute attacks of angina pectoris. — EMA SPC

Drug interactions

HighSildenafilG04BE03
Mechanism: Pharmacodynamic synergy. Nitrates increase cGMP production, while PDE-5 inhibitors prevent its degradation. This leads to profound vasodilation and life-threatening hypotension.
Recommendation: Concomitant use is absolutely contraindicated. A minimum of 24 hours must elapse between taking sildenafil and administering a nitrate.
EMA SPC
HighRiociguatC02KX05
Mechanism: Riociguat directly stimulates soluble guanylate cyclase (sGC), and nitrates also activate it via nitric oxide. Co-administration potentiates the cGMP pathway, causing a high risk of hypotension.
Recommendation: Concomitant use is contraindicated due to the high risk of hypotension.
EMA SPC

Adverse events

Common (≥1%)

headache · hypotension · dizziness · nausea · asthenia

Rare but serious

syncope · circulatory collapse · methemoglobinemia

Pregnancy and lactation

Should not be administered during pregnancy and lactation unless, in the physician's judgment, the benefit to the mother outweighs the potential risks to the fetus or infant.