How long should it take from stopping Ashwagandha to taking Brintellix?

Unfortunately, it is difficult to find an answer to this question, because it is difficult to determine exactly what relationship to "look for" in the context of a potential interaction. However, it seems that the need to start treatment as soon as possible is more important than the search for an interaction that may not be clinically significant. To the best of my knowledge, it seems sufficient to simply stop using the ashwagandha product and start treatment with the medicine prescribed by your doctor. If you have doubts, I encourage you to consult an individual doctor, because he can give specific advice, knowing your health situation. Above I have only presented my interpretation of the information available to me. I leave a link to an article that may interest you: https://www.gdziepolek.pl/artykuly/depresja