2,2',2'',2'''-[(4,8-Dipiperidinopyrimido[5,4-d]pyrimidine-2,6-diyl)dinitrilo]-tetraethanol

Absorption
Two minutes after a 4 min IV infusion, the mean serum level is 4.6 mcg/mL.

Distribution
Highly bound to plasma protein (99%). Vd is 1 to 2.5 L/kg.

Metabolism
Metabolized in the liver (conjugated as a glucuronide).

Elimination
Excreted in the bile. Average total body Cl is 2.3 to 3.5 mL/min/kg. The alpha t½ (initial decline following Cmax ) is about 40 min, while the beta t½ (terminal decline in plasma level) is approximately 10 h (oral). Triexponential: the t½ range is 3 to 13 min, 33 to 62 min, and 11.6 h (IV).

Peak
The average time to C max is about 75 min.

Adenosine
Plasma levels of adenosine may be elevated, increasing the CV effects.

Cholinesterase inhibitors
Anticholinesterase effects may be counteracted by dipyridamole, potentially aggravating myasthenia gravis.

Theophyllines, xanthine derivatives (eg, caffeine)
May abolish coronary vasodilation induced by IV dipyridamole.