1,2,3-trinitroxypropane 1,3-dinitrooxypropan-2-yl nitrate propane-1,2,3-triyl trinitrate

Absorption
Rapid.

Distribution
Vd is 3 L/kg. Protein binding is approximately 60% (parent); 1,2 dinitroglycerin, 60%; 1,3 dinitroglycerin, 30%.

Metabolism
Primarily metabolized in the liver by nitrate reductase; known sites of extrahepatic metabolism include red blood cells and vascular walls. Metabolized to inorganic nitrate and the active 1,2 and 1,3 dinitroglycerols.

Elimination
Serum t ½ is 3 min and 1 to 8 min (sublingual). Cl is 1 L/kg/min.

Onset
1 to 2 min (IV), 1 to 3 min (sublingual), 1 h (extended-release).

Peak
1 to 4 h (immediate-release tablet), 6 to 7 min (sublingual), 2 h (transdermal).

Duration
3 to 5 min (IV), 30 to 60 min (sublingual), 5 h (extended-release), up to 12 h (topical ointment).

Alcohol
Severe hypotension and CV collapse may occur.

Alteplase
Concurrent administration decreases thrombolytic effects of alteplase.

Aspirin
Vasodilatory and hemodynamic effects of nitroglycerin may be enhanced.

Calcium channel blockers
Symptomatic orthostatic hypotension may occur.

Dihydroergotamine
May increase systolic BP and decrease antianginal effects.

Heparin
May decrease anticoagulation effect when used in conjunction with IV nitroglycerin.

Phosphodiesterase type 5 inhibitors (eg, sildenafil, tadalafil, vardenafil)
Because the hypotensive effects of nitrates may be potentiated, concomitant use of any form of organic nitrates is contraindicated in patients receiving phosphodiesterase type 5 inhibitors.