EFFECT OF FOOD AND ANTACID ON ABSORPTION OF ORALLY-ADMINISTERED TICLOPIDINE HYDROCHLORIDE

Ticlopidine is a potent inhibitor of platelet aggregation. Absorption of ticlopidine after oral dosing is rapid and complete. Ticlopidine is extensively metabolized with a relative minor component of unchanged ticlopidine in plasma. The randomized crossover study described here was undertaken to examine the effect of food and antacid on the oral bioavailability of a single dose of ticlopidine (250 mg) in normal volunteers. After post-prandial treatment the rate and extent of absorption of ticlopidine was earlier and greater relative to fasting treatment [t(max) = 1.71 ± 0.33 hr (fed) vs 1.92 ± 0.56 hr (fasting) and AUC(0-∞) = 2.164 ± 0.813 μg x hr/mL (fed) vs 1.808 ± 1.052 μg x hr/mL (fasting)]. The oral bioavailability of ticlopidine was increased by 20% when taken after a meal. In contrast, absorption of ticlopidine administered after antacid treatment was approximately 20% lower than under fasting conditions. Administration of ticlopidine with food is recommended to maximize gastrointestinal tolerance.