Why would a doctor drug test you? The Doc might ask you if you are using any medication or recreational drugs depending on the situation. What's the reason you're going to the doctor?
Doctors can NOT drug test adults 18+ years old unless they ASK the patient if it is ok first...i.e..they can not FORCE an adult to take a drug test.
if your are in the crisis/pysch area although you have the right to refuse treatment, but it all depends on the dr
I'll assume you're a minor and don't want your parents to find out. Nothing that I'm aware of can actually get it out of your system other than time. You can dilute though just depends how deep the drug test is.
You know, it's okay to tell your doctor that you smoke marijuana. I tell them, whether they ask or not, because this is about YOUR health, and they need to know anything that could have anything to do with whatever you're going to see them about. Now, 10 years ago, this wouldn't be the case, as doctors were still on the "marijuana is as bad as meth" kick. I went in a couple months ago, because I couldn't stop vomiting, and I told him I smoke marijuana. He said "Marijuana actually relieves/helps vomiting, so it's not that." Mind you I live in a completely illegal state.
The time where a doctor will drug test you is if you are prescribed a scheduled drug. You often need to sign a contract with the doctor, If they think you are selling, abusing or not taking the medicine, they will test you to see if it is in your system. With certain medicine, the patient must see the doctor every 3-6 months to keep the prescription.
When I played football in high school and had to get physicals I'd never get piss tested at my regular doctor's office (he worked at Kaiser Permanente), but when my family switched to a private doctor they did drug test me. Luckily I wasn't regularly smoking weed back then.
When I had a chest cavity inflammation problem last year I didn't care if the doctor knew if I smoked or not. The nurse that asked me didn't care about it, she just asked is there anything else which there wasn't. The doctor even said that my lungs them self look completely fine and that weed hasn't done anything bad.