| abstract |
Use of tramadol in the manufacture of a controlled release analgesic preparation for once-daily oral administration, in which (a) the preparation contains between 1 and 80% weight / weight of at least one hydrophilic polymer, and an analgesically effective amount of tramadol HCl in a controlled release matrix and exhibits the following in vitro dissolution rate when measured using the Ph. Eur. Paddle Method at 100 rpm in 900 ml of 0.1 N hydrochloric acid at 37 ° C and using a UV detection at 270 nm: between 0 and 30% (by weight) of tramadol released after 1 hour, between 0 and 40% (by weight) of tramadol released after 2 hours, between 3 and 55% (by weight) of tramadol released after 4 hours, between 10 and 65% (by weight) of tramadol released after 8 hours, between 20 and 75% (by weight) of tramadol released after 12 hours, between 30 and 88% (by weight) of tramadol released after 16 hours, between e 50 and 100% (by weight) of tramadol released after 24 hours, more than 80% (by weight) of tramadol released after 36 hours; or (b) the controlled release preparation comprises a tramadol or a salt thereof incorporated into a normal release matrix, which is a spheroid comprising the pharmaceutically acceptable tramadol or salt thereof and a spheronizing agent, the spheroid having a coating of Controlled release selected from water insoluble waxes, water insoluble polymethacrylates and water insoluble cellulose. |