Do you drug test before letting someone donate

No they don't. If it's suspected, yes they will. Every donation is tested for std's and marijuana is fine. Nothing you can inject is allowed

They test each donation you make, and will be put on a deferral list if you ever fail. I think the list is federal

They do test your plasma after they have it each time for disease and drugs... weed is not a issue

Csl does not but some donation centers do.

No.