Will a Doctor Cancel a Liposuction if I Have Thc in my System?

I don't know of any plastic surgeon who tests for THC prior to surgery. It's important that you report to him or her that you smoke marijuana but I would be surprised if it had any effect on their decision to perform surgery.

Most plastic surgeons don't test for THC prior to surgery. You should, however, report your smoking to your surgeon and let him/her decide their plan of action. They may proceed or they may postpone due to cigarette smoke inhibiting the body’s ability to heal. It would be in a patient’s best interest to quit smoking well before a procedure. – Dr. Ortiz

We do not screen for THC.  No one would because it is not relevant to surgery.  Smoking with cigarettes is far worse for healing, so make sure you stop those.

There are many opinions regarding the answer to your question, however the most important one is the opinion of your surgeon, who knows the circumstances surrounding your surgery. I can tell you that I would be more likely to discuss options with a patient who was honest with me beforehand, and much more likely to cancel or postpone the surgery if I discovered from a blood test, the attempt to hide the information from me.

I would recommend that you speak to your surgeon. If the surgery is ultimately postponed it is likely for your safety and best outcome.

Good luck