Is it common for doctors to require a pee test before having a gastric bypass and if so what for?

Hello, I hope you are well. Yes, it is very commo for surgeons to ask for an urine test prior to a gastric bypass, as well as plenty other types of surgeries. This is sometimes one of the routine pre operative tests. Surgeons ask a urine test in order to make sure you are not currently coursing with a urinary tract infection, which are commonly asymptomatic and may require antibiotics.

A urine test is also commonly done for female patients do ensure that they are not pregnant. Also, as mentioned before, sometimes it is done to check for nicotine as well.

While not all doctors require this, it is very common.
The main reason is to check for nicotine (tobacco) use.
Nicotine use can cause significant complications after gastric bypass so we want to ensure that our patients are not using it