The time it takes for a pill to work depends on the type of medication and its purpose. Some pills, like certain birth control pills taken at the right time, can start working immediately or within a day. Others, such as antidepressants, may take several weeks (2-12 weeks) to show their full effect. For many painkillers taken orally, the onset of effect can be within about 20 to 60 minutes as the pill dissolves and the active ingredient is absorbed in the small intestine. How fast a pill works can also depend on factors like body metabolism, stomach contents, and posture when taking the pill. For birth control pills specifically:
- Combination pills taken within the first 5 days of your menstrual cycle work instantly.
- If started at any other time, combination pills take about 7 days to become effective.
- Progestin-only pills may work immediately if taken early in the cycle but generally take about 2 days to start working if started later in the cycle.
- After pregnancy or termination, timing can affect immediate effectiveness as well.
For other medications:
- Some medications start working on the first day (e.g., some blood pressure medications).
- Others, like cholesterol drugs and antidepressants, take weeks to months for full effect.
The pill's dissolution can be faster if taken lying on the right side—about 10 minutes to dissolve, then absorption in the intestines follows. In summary, how quickly a pill works varies widely but generally ranges from minutes to weeks depending on the medication type and circumstances.
