Washout Period Explained

A period during a clinical trial when the trial subjects receive no active medication. The wash-out period is typically used to generate patient baseline data.   Every clinic has a washout period during which you are not allowed to do a study at the same clinic or any other clinic. The minimum period is 30 days since last dose, however some washouts go based on last study procedure (such as out patient visits or how much blood you gave during the study).   The washout period may vary from study to study depending on the half-life of the drug. Certain studies like radio-labeled drugs will have a 1 year washout before you can do another radio-labeled drug.   In addition to the clinic’s washout policy, the sponsor may impose a longer washout period.  Some studies will have a longer washout before you can sign up. In general, you can sign up and screen for another study during the washout period as long as the check in date is at least 30 days after your last dose in the previous study.  However, depending on how fast your body recovers from a study, you may want to wait the full period to avoid problems with screening. People who screen too soon after a study typically have lower red blood cell, hemoglobin, hematocritand iron.  If these levels are too low, you could get banned from participating in studies because having low levels is unhealthy and unsafe for participating in a study. Be forewarned that many clinic participate in the VCT (Verified Clinical Trials) program which tracks when you do a study to ensure the next study meets washout periods.  I do not mention these clinics because it shouldn’t matter.  You know the rules and if you break them, the consequences can be dire like being banned from a clinic.  Sometimes the only way to drive this message home is to allow people to find out the hard way. –  –  National Institute of Health