Does marijuana change the shape of the nose after Rhinoplasty?

Thank you for the question. You should absolutely consult with your physician about your smoking habits in order to obtain the most reliable and individualized medical advice. Most specialists recommend abstaining from smoking for 2-3 weeks before a rhinoplasty, while others may insist on a full month or two. Smoking will cause irritation and restrict the blood flow to your healing areas, possibly causing complications during the recovery period.   
In addition, you should also make sure to avoid smoking for at least two weeks after surgery as it may interfere with your healing process. Even though it is not likely to change the shape of your nose, smoking after surgery may restrict the flow of blood to the healing areas, exacerbate swelling, and prolong recovery. Of course, as a physician, I would advise you to quit smoking altogether due to a variety of health risks associated with it. 
 An in-person exam with a board-certified plastic surgeon would be the best way to assess your needs and obtain expert medical advice. Best of luck! 

Smoking impacts wound healing and it is probably best to avoid it during the first several weeks after surgery as well.