Steady state

The point at which the amount going in equals the amount being cleared.

When a medication is taken repeatedly, its concentration in the body climbs until the amount absorbed with each dose matches the amount eliminated between doses. From then on the level fluctuates around a stable average rather than continuing to rise. Reaching steady state typically takes four to five half-lives, which is why some medications feel weak for the first week and why a dose change is not fairly judged on its first day.

The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.