Can I participate if I'm already taking medication?
Yes, in many studies — but it depends on the specific protocol. Some clinical trials are designed for patients who are stable on a current medication and want to test an add-on therapy. Others compare an investigational drug to a participant's existing regimen. A smaller group, especially first-in-human Phase 1 studies, require a 'washout period' during which you taper off certain medications under medical supervision before the study begins. The IRB and FDA require that any medication change is done safely, which is why the research coordinator will ask for a complete list of your prescriptions, over-the-counter drugs, and supplements during the screening call. Never stop a medication on your own to qualify — the site's physician will create a safe plan if a washout is needed. Bring your medication list (or a pharmacy printout) to the screening visit to speed the process.