Stability of diltiazem in different biological fluids

The hydrolysis of diltiazem in biological fluids: whole blood, plasma, and gastric fluid was investigated under conditions considered close to the physiological situation. The most significant rate of hydrolytic degradation was found in whole blood (half-life of 27 h), followed by plasma (half-life of 88 h), while the least significant degradation rate was observed in gastric fluid (half-life 153 h). The kinetic profiles of diltiazem hydrolysis indicate that hydrolytic degradation in the biological fluids makes a minimal contribution to the clearance and disposition of the drug.