GW Gastroenterology & Liver Diseases: Colonoscopy Preparation Guide

 

Prep Timeline

Medication Guidance

Substances & Safety

Diet Instructions

Bowel Preparation

Low Fiber Diet

What to Expect

Contact Us

At GW, we’re committed to making your care as smooth and stress-free as possible. Preparing for your colonoscopy is an important step to ensure accurate results and a safe experience. Please follow the instructions below carefully, and reach out to your care team with any questions.

Your Prep Timeline

4 days before your procedure

  • Begin a low-fiber diet 
  • Review medications and adjust as needed 

1 day before your procedure

  • Switch to a clear liquid diet
  • Start your bowel preparation 

Day of your procedure

  • Complete your prep
  • Stop all liquids at least 4 hours before 

Medication Guidance

Before your procedure, some medications may need to be paused or adjusted. If you’re unsure about any medication, we encourage you to contact your care team; we’re here to help.

Blood Thinners (Important)

These medications may increase bleeding risk and often need to be paused:

  • 5 days before: warfarin, clopidogrel, ticagrelor 
  • 2 days before: apixaban, rivaroxaban, dabigatran, edoxaban 
  • Enoxaparin: Do not take the night before or day of your procedure 
  • Aspirin: Please check with your care team

Blood Pressure Medications

  • Beta blockers: Take as usual, including the morning of your procedure 
  • ACE inhibitors & ARBs: Hold the morning dose 
  • Entresto: Hold the night before and morning of

Diabetes Medications

  • Insulin: Please contact your care team for specific instructions 
  • SGLT2 inhibitors (e.g., Jardiance, Farxiga): Stop 3 days before 
  • Other diabetes medications: Hold the night before and morning of 
  • Weekly injections (e.g., Ozempic, Wegovy): Hold 7 days before

Weight Loss Medications

  • Daily medications: Hold 1 day before 
  • Weekly injections (e.g., Ozempic, Wegovy): Hold 7 days before 
  • Phentermine: Hold 7 days before

Pain Relievers & Anti-Inflammatories

  • NSAIDs (ibuprofen, naproxen, etc.): Stop 7 days before 
  • Acetaminophen (Tylenol): Safe to use

Vitamins & Supplements

  • Stop 1 week before:
    • Herbal supplements (such as ginkgo or St. John’s wort) 
  • Stop 5–7 days before: 
    • Fish oil / Omega-3
  • Do not take vitamins the morning of your procedure

Other Medications

  • Diuretics (water pills): Hold the morning of your procedure 
  • Inhalers: Bring them with you 
  • Neurologic and mental health medications: Usually safe to continue 
  • All other medications: Please check with your care team if you’re unsure

Substances & Safety

Your safety during sedation is our top priority.

  • Avoid recreational substances in the days leading up to your procedure as some substances can affect anesthesia or increase risks 
  • If you take any substances including: cocaine, marijuana, heroin, methadone, naptrexone, please contact your provider.
  • If you take medications such as Suboxone or similar therapies, follow guidance from your prescribing provider

Diet Instructions

7 Days Before Your Procedure

Follow a low-fiber diet to help prepare your digestive system. Please see below for suggested low-fiber foods.

Day Before Your Procedure

Follow a clear liquid diet only:

  • Water, broth, tea, black coffee
  • Clear juices (without pulp)
  • Sports drinks, gelatin
  • Avoid anything that is red or purple dyed

Please avoid red or purple liquids

Bowel Preparation

Your provider will prescribe one of the following options. Follow the instructions carefully for the best results.

SUPREP®

Day Before

  • 4:00 PM: Take 2 Dulcolax tablets 
  • 5:00 PM: Drink the first prep mixture (16 oz) 
  • Then: 
    • 30 minutes later: Drink 16 oz of water
    • 1 hour later: Drink another 16 oz of water 

Day of Procedure

  • Repeat with the second bottle
  • Finish all liquids at least 4 hours before your procedure 

COLYTE® (One-Day Prep)

2 Days Before

  • Mix the prep and refrigerate.

Day Before

  • 4:00 PM: Take 2 Dulcolax tablets
  • 5:00 PM: Drink half of the prep (8 oz every 10–15 minutes)

Day of Procedure

  • Begin 7 hours before your procedure 
  • Finish remaining prep at least 4 hours before

COLYTE® (Two-Day Prep)

2 Days Before

  • Mix prep and refrigerate 

Day Before

  • Clear liquid diet
  • 4:00 PM: Take 2 Dulcolax tablets
  • 5:00 PM: Drink half of the first bottle

Next Morning

  • Finish the first bottle 

Evening Before Procedure

  • 5:00 PM: Drink half of the second bottle

Day of Procedure

  • Begin 7 hours before your procedure 
  • Finish all prep at least 4 hours before

Low Fiber Diet

 Breakfast Options

  • White toast with butter or jelly (no seeds) 
  • Scrambled or boiled eggs 
  • Plain bagel 
  • Low-fiber cereals (e.g., cornflakes, puffed rice) with milk 
  • Yogurt (no fruit chunks, seeds, or granola) 
  • Pancakes or waffles (plain)

 Lunch Options

  • White bread sandwich (turkey, chicken, egg salad, or tuna) 
  • Plain pasta or white rice 
  • Baked or grilled chicken (no skin) 
  • Clear soups or broths (strained chicken, beef, or vegetable broth)
  • Saltine crackers 

 Dinner Options

  • Lean meats: chicken, turkey, fish 
  • White rice or plain pasta 
  • Mashed potatoes (no skin) 
  • Cooked vegetables without skins/seeds (e.g., carrots, green beans) 
  • Dinner rolls (white bread)

 Snacks & Sides

  • Applesauce 
  • Bananas 
  • Canned fruit (peaches, pears - no skins) 
  • Pudding or custard 
  • Cheese sticks 
  • Pretzels or plain crackers

 Beverages

  • Water 
  • Tea or coffee (no cream if instructed) 
  • Clear juices (apple, white grape) 
  • Sports drinks (avoid red/purple coloring if instructed)

 Foods to Avoid

  • Whole grains (brown rice, whole wheat bread, quinoa) 
  • Nuts, seeds, popcorn 
  • Raw fruits and vegetables 
  • Beans and legumes 
  • Tough meats or fried foods 
  • Anything with skins, pulp, or high fiber

What to Expect

  •  Frequent bowel movements as your system clears 
  • Mild bloating or cramping is normal 
  • You may take Gas-X (simethicone) if needed

Before You Arrive

  • Arrange for someone to drive you home 
  • Do not eat or drink anything within 4 hours of your procedure 
  • Follow all instructions closely for the best possible results

Contact Us

If you have questions about your medications or preparation, please contact GW Gastroenterology & Liver Diseases at (202) 741-2160. We’re here to support you every step of the way.