Washout Period — What It Means in Clinical Trials
Plain English Definition
A washout period is a set amount of time before or during a trial when you must stop taking certain medications so they can clear from your body. This ensures the study drug is tested without interference from other treatments. Your doctor will tell you exactly which drugs to stop and for how long.
Why It Matters
If a trial requires a washout period, you may need to go without your current medication for days or weeks. Discuss this with your doctor to make sure it is safe for you and that you understand the risks.
Example
A listing might say: "A 28-day washout period from prior chemotherapy is required before the first dose of the study drug."
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