Tramadol Pharmacokinetics

After being taken orally, Tramadol hydrochloride is rapidly and virtually completely absorbed. There is an approximately 75% mean absolute bioavailability associated with a 100 mg dose. In healthy adults, the mean peak plasma concentration of racemic Tramadol occurs at two hours, and at 3 hours, the mean peak plasma concentration of M1 occurs. Within two days of oral administration, steady-state plasma concentrations of Tramadol and M1 occur. No evidence of self-induction exists.

Figure 1: Mean Tramadol and M1 Plasma Concentration Profiles after a Single 100 mg Oral Dose and after Twenty-Nine 100 mg Oral Doses of Tramadol Hydrochloride given q.i.d.