Compounding and Stability Study of Dipyridamole and Clopidogrel Pediatric Oral Suspensions.

Dipyridamole and clopidogrel are two antiplatelet agents that can be prescribed off-label in pediatric practice. As commercially available drugs are unavailable, pediatric formulations must be compounded. Both stability-indicating HPLC dosing assays and microbiological methods were validated and described. Stabilities of dipyridamole and clopidogrel in Syrspend® pH4 were studied. The stability study of clopidogrel involved two complementary HPLC methods (RP-HPLC and chiral HPLC). Oral suspension of 10 mg.mL-1 dipyridamole is stable for 3 months at +2/+8°C before opening, 1.5 month at +2/+8°C after opening, and 15 days at 25°C/60% RH. Oral suspension of 5 mg.mL-1 clopidogrel bisulfate is stable only for 1 month at +2/+8°C before or after opening and for 7 days at 25°C/60% RH.