Preparing for Weight Loss Surgery

Bowel Preparation

Starting 48 hours (for gastric bypass surgery) or 24 hours (for adjustable gastric band surgery) prior to your surgery, you are to have only clear liquids. Clear liquids include water, apple juice, cranberry juice, decaffeinated tea without milk, Crystal Light, ginger ale, 7-Up, etc. You may have all that you want, but it is all you are to have.

Blood Type & Screen

If you are having gastric bypass surgery (not band surgery), you will need to have blood drawn for a type and screen within 14 days prior to surgery. This must be drawn at the Cedars-Sinai Anesthesia Pre-Procedure Evaluation Center.

Anesthesia Pre-Procedure Evaluation Center

The center is in the South Tower on the Street Level, Room 1720. If you have been pregnant or received a blood transfusion within 3 months prior to surgery, the specimen must be drawn no more than 3 days prior to surgery. It is our strong recommendation that you make an appointment for this draw as you will have to wait to be worked in if you just walk in. To make an appointment, please contact the center at 310-423-4068, Monday-Friday 9 a.m.-5 p.m.


Do not take aspirin or medications containing aspirin 1 week prior to surgery unless otherwise instructed. If you take herbal supplements on a regular basis, please advise the nurse at the time of your pre-op appointment as these may also need to be stopped.

Changes in Health

If there are any changes in your general health prior to your scheduled surgery day, such as fever, cough, cold, etc., please report this to the nurses in the clinic. If it occurs on the weekend and you are scheduled for Monday, please call the clinic at 310-423-8350, and ask to speak with the physician on call.


Please leave all valuables at home.

What to Bring With You

Please bring your picture ID and insurance card. If you have a cell phone, please have it turned on and with you that day, and be sure the clinic staff has this number on file.

Advance Directive

Bring a copy of your Advance Directive, if you have one. You have the right to make decisions about your healthcare. This includes the right to accept or refuse medical or surgical treatment. But if you become seriously ill, you may lose the ability to participate in decision-making about your own treatment. Fortunately, you have the right to plan and direct the types of health care you wish to receive in the future. You can do this by making an Advance Directive. This document gives you a voice in decisions about your medical care when you are unconscious or too ill to communicate. If you would like to create an Advance Directive, you may obtain the forms at the Cedars-Sinai information desk, or download them at our Advance Directives page.


Park in the South Tower parking structure. Inform the parking attendant that you are here for surgery, and the parking fee will be waived. (Visitors will pay regular parking rates.)

Medical Campus Map & Parking Maps.


Please check in at the registration desk in the South Tower, Street Level, 2 hours before your surgery time.


If you have any questions concerning any of the instructions or any other part of the surgical process, please call us at 310-423-8350.