EXTENDED RELEASE COMPOSITION CONTAINING TRAMADOL

摘要

The present invention relates to a once daily extended release pharmaceutica l preparation of Tramadol or its acceptable pharmaceutical salts. The preparation provides, effective blood concentration for a period of about 24 hours with reduced peak concentrations. It is characterized that effective Tramadol levels appear within the first hours after administration, the time to maximal Tramadol content Tmax is at least 10 hours and the peak Tramadol concentration is less than three times the concentration obtained after 24 hours of said administration.