I feel nauseated after starting to drink my colonoscopy prep, what should I do?
Feeling nauseated after starting your colonoscopy prep is a common side effect, especially in the first hour or so. The prep solution can be hard on the stomach due to its taste, volume, and the rapid changes it causes in your digestive system.
Here’s what you can do to help manage the nausea:
Slow Down
- Try sipping the prep more slowly, in small amounts every few minutes instead of chugging it.
- You can pause for 15–30 minutes if the nausea is intense, then resume at a slower pace.
Chill It
- Refrigerate the prep solution — cold prep is usually easier to tolerate.
- You can also drink it through a straw placed at the back of your mouth to avoid the taste.
⚠️ When to Call Your Doctor:
- Vomiting repeatedly
- Unable to keep any prep down
- Dizziness or lightheadedness
- History of severe nausea or GI issues with prep
I haven't had any bowel movement since drinking my colonoscopy prep but I do not feel bad. What should I do?
It’s not unusual for the bowel movement to take several hours to start after you begin your colonoscopy prep, especially if:
- You haven’t finished the full dose yet
- You tend to have a slower digestive system
- You haven’t eaten much in the last 24–48 hours
Here’s what you should do:
Give it More Time
- Some people don’t have a bowel movement for 2–4 hours after starting the prep.
- If it’s been less than 4 hours, it’s usually okay to wait and keep drinking the prep as directed.
Keep Drinking
- Make sure you're drinking all of the prep solution (unless told otherwise).
- Also drink clear fluids (water, broth, electrolyte drinks) in between to help things move.
Walk Around
- Gentle walking or light movement can help stimulate your bowels.
⚠️ Call Your Doctor If:
- It’s been more than 4–6 hours since starting the prep and you haven’t had any bowel movement at all.
- You can’t finish the prep due to nausea or fullness.
- You have a history of chronic constipation or bowel obstruction.
- You’re unsure if the colon will be clean enough for the procedure.
I just vomited most of what I drank of my colonoscopy prep, what should I do?
Vomiting during colonoscopy prep can be distressing, but you're not alone. It does happen to many people, and you should not try to continue right now without a pause and guidance.
⚠️ Here’s what you should do right now:
1. STOP drinking the prep for now
- Give your stomach a break for 30–60 minutes.
- Don’t try to force more down — it could just come right back up again.
2. Call your doctor or the on-call GI provider ASAP
- Let them know:
- How much prep you were able to keep down
- That you vomited
- Whether you’ve had any bowel movement yet
- While you’re waiting to hear back, try this in the meantime:
- Rest and stay upright (don’t lie down flat)
- If you can’t keep the prep down, slow deep breaths will also help reduce nausea.
- Our providers are used to managing this issue — it’s far better to wait for their advice than to try and push through.
I hear my stomach gurgling a lot after drinking the colonoscopy prep but I have not had any bowel movement yet. Is that a problem?
No, it’s not a problem — in fact, gurgling or rumbling sounds in your stomach are a good sign that the colonoscopy prep is starting to work.
Why You Hear Gurgling:
- The prep is pulling water into your intestines to flush everything out.
- Gurgling sounds (also called borborygmi) mean that your GI tract is active — your intestines are moving and preparing to empty.
But No Bowel Movement Yet?
That can still be normal, especially if:
- It’s been less than 3–4 hours since you started
- You haven’t finished the full prep dose
- You tend to have slower digestion or constipation
Some people don’t have their first bowel movement until several hours after starting.
What You Should Do:
- Keep Drinking the Prep as instructed — that’s the key to getting things moving.
- Walk around gently to stimulate your bowels.
- Be patient — the first bowel movement often takes a while, but when it starts, it usually happens quickly.
⚠️ When to Worry:
Call your doctor if:
- It’s been more than 6 hours with no bowel movement
- You vomited most of the prep
- You’re feeling very bloated, in pain, or dizzy
- You have a history of severe constipation or bowel obstruction