The answer is…it depends. One way to answer when a drug will be out of your system refers to half-life. So if you are wondering when our lab would be unable to detect any trace of your chemotherapy in the tissues of your body, it would depend on the half-life of that drug. Because that is a characteristic of each drug, this could range from minutes to weeks. However, many times, what patients really want to know when they ask this question is when they will begin to clear the drug so they start to feel better from the side effects. In that case, the answer is most acute effects of chemotherapy resolve within 2-5 days of treatment. If you do not feel better at this time, or if your side effects are difficult to manage at any time, please talk to your physician or even your nurse. Many supportive care medications are available to assist patients with the side effects of chemotherapy.