| abstract |
Provided is a method for preparing a sustained release oral preparation containing an active drug such as an opioid analgesic, which is resistant to tampering. (1) combining at least one polyethylene oxide having an approximate molecular weight of at least 1,000,000 based on rheological measurements and (2) at least one active agent to form a composition; (B) molding the composition to form a sustained release matrix formulation; and (c) subjecting the sustained release matrix formulation to a temperature that is at least the softening temperature of the polyethylene oxide for at least about 1 minute. A method for preparing a sustained release oral preparation comprising at least a step of curing the sustained release matrix preparation, comprising at least a curing step. [Selection figure] None |