Do not take a detox drink. Call a collection facility or surf the net and find out what "control drugs" are. According to another board that I visit, stuff like antibiotics, ADD medications, and other types of prescribed medications are not ferreted out on the typical EMIT 5 or 10 panel test. Also, tests have been modified so that otc pain medications like ibuprofen and cold or cough medications, do not register as a "false positive."

There's a good chance that the medications you are on for cholesterol and blood pressure are not on the list of control drugs.

Don't know how many days you are clean, but keep abstaining. Pot leaves the blood stream within 24-48 hours. I'd sub. Don't let these jerks come into the bathroom with you to observe (they probably won't). If they do, refuse the test and call your school. Tell them you can't pee with people watching you and buy yourself some extra time.

Since your test isn't until 8/19, test yourself in the meantime. With your level of activity, you might already test clean on a home test.