If the facts are true, you can sue. The problem will be that besides the confinement, you don't have an injury. You may be able to find an attorney who is willing to take on this case. Any attorney is going to want to see the medical records for this event plus any other presentation to a health care provider for substance abuse/withdrawal for the last 10 years or so. This will help the attorney estimate the value of the case.
Ben Glass is licensed in Virginia. He offers a number of free consumer book downloads at his site for information purposes only. You should consult an experienced, board certified attorney in your area. Obviously, no attorney client relationship is formed by participating in Avvo.
If your facts are correct, you may have a case. As the previous answer stated, you may not have any damages. If you have no damages, suing is probably not economically reasonable as you will have to pay the costs of the case to pursue it. If the doctor did think you were not competent that can have a TRO (temporary restraining order) issued to hold you for a short period of time. Your facts do not sound like that was done, though.
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