Can your doctor administer a drug test without your consent?
They will have to have your permission.
Doctors do nothing without consent, although it should be noted that an unconscious person, who is unable to either give or withhold consent, may be construed to give "implied consent" (that is, we may assume he or she would consent, if he or she were conscious). The second half of your question, is there a proper way to perform, is not clear. What kind of performance do you have in mind?
Can law enforcement pretend to be you without your knowledge or consent during a drug investiagtion?
If this is a hospital setting in the US or the western world, then no, a nurse cannot administer any drugs without a active doctor's orders or without consulting with the doctor. Sometimes if the order is in the "PRN" or as needed section of the chart, the nurse may administer the drug if the patient requests it or is in pain (or whatever the patient is being treated for with those drugs).
A Psychiatrist is a physician with a medical degree (Doctor of Osteopathic Medicine (D.O.) (U.S.-trained only) or Doctor of Medicine (M.D.) that specializes in psychology. They can administer drugs as part of the treatment. A Psychologist is a PhD - in most cases - and cannot administer any type of drug therapy.
I'm 17 and everywhere I went they refused to drug test me because I didn't want it and I was not in any immdiate danger. I was not using drugs, but my grandparents were trying to do it anyways. If you are so concerned about it, try to find a reason to take your child to a doctor, if the doctor thinks it needs to be done, well they will do it.
Can a pharmacy switch the proscribed drug from the doctor to the generic drug without even informing the person taking the drug?
No they cannot. A psychologist is not an MD, therefore they cannot use medication of drug therapy. A psychiatrist on the other hand is an MD with a specialty in psychiatry, and can prescribe and administer medication and various kinds of drug therapy. No they cannot. A psychologist is not an MD, therefore they cannot use medication of drug therapy. A psychiatrist on the other hand is an MD with a specialty in psychiatry, and…