Plasma concentrations of racemic tramadol are predictable over a 50 mg to 100 mg single-dose range. This is also true under multiple-dose conditions. Steady state is achieved after two days of dosing Ultram by a 100 mg q.i.d. regimen (maximum plasma concentration was 592 � 177 ng/ml). The plasma half-life of tramadol following a single and multiple dosing was 6 and 7 hours, respectively. This increase in half-life upon multiple dosing is not considered to be clinically significant or to warrant dosage adjustment for chronic use.

Really long half-life. Don't overdo it.