That depends on the re-hab, but most will give you Tylenol for aches and pains. Mylanta or an alternative for heartburn. The list is long - but they won't give you anything that is considered "mood altering."
You shouldn't take drugs unless they are prescribed to you by a doctor, or something OTC and used properly.
Viagra
Drugs such as children's Advil and Motrin, Aleve, Pepcid and Tagament are available in OTC in the United States.
OTC drugs are not made for everybody
Believe it or not MOST drugs take even longer to get off of than what rehab keeps you for. That's why 90% of all drug addicts relapse.
OTC drugs are notoriously misused. One needs some drug to fulfil his addiction, he pays some extra bucks to buy over the counter drugs. Even for those who couldn't afford the prescription from a doctor, he risks his health by getting an otc drugs from someone.
OTC
What are you treating? if withdrawals from drugs best to stick it out, some OTC drugs will help. opiates = immodiom, just for constipation though. if treating from an infection, illness, etc. i wouldn't recommend OTC. consult a physician!
Dougie Poynter doesn't take drugs, he was in rehab because of depression due to his break up with Frankie Stanford.
Dramamine, Diphenhyramine:)
Luride drops
teens can go to a rehab or go and take drug class at there local na meetings