Dosage and administration according to the Japanese prescription label of prasugrel are as follows: prasugrel should be initiated with a single 20-mg oral dose and then continued at a 3.75-mg once-daily oral dose as a maintenance dose . Prasugrel was administered as 3.75- and 5-mg tablets, in combination with aspirin (81–100 mg/day; up to 324 mg could be used as an LD). Patients receiving a prasugrel dose of 3.75 mg during approximately 5 days prior to PCI did not require an initial LD. The extent of the exposure to prasugrel and the timing of prasugrel administration (before, during, or after PCI) under the actual conditions of use were examined.