Weeks. The answer is a bit vague, because patients often start deliberately on lower-than-needed dosages to minimize side effects. The "clock starts ticking" when you get to a therapeutic dose, which can vary from person to person but usually is in the range of 1.2-1.4 mg/kg/day. Then, it can take 2-4 weeks to start showing benefit, with continued enhanced benefits potentially up to 6 months.
Strattera (atomoxetine) With proper dosing over 2-3 weeks, it usually takes 4-6 weeks to see full effects.
Not a stimulant. Strattera (atomoxetine) definitely not fast acting, often taking several weeks to affects adhd symptoms. It must be taken daily, and the dose may need to be raised slowly to minimize se. However, when it does work, it provides 24-hour coverage of adhd symptoms and benefits can continue to build for 6 weeks or longer. Sadly, it does not work as often as stimulants; but, when it does, it can be a real boon. Read more...