How long does a drug stay in my system?

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Q. I started having side effects from a prescribed drug. I stopped taking it, but the side effects are still there. How long does it take for a drug to be out of your system?

A. Most drugs will be out of your system quite quickly, but the symptoms of side effects may remain for some time. It depends on the medication and what kind of side effect has developed. The majority of prescription drugs are cleared out of your body rapidly by your kidneys and liver. Trace levels of a medicine may remain in the system while the liver and kidneys finish their filtering job. But these levels are often too low to have any noticeable effect. Patients with kidney or liver disease, however, can continue to have elevated blood levels of a drug even after stopping it.