If you have chosen to have Penthrox to assist with your procedure, you do not need 24 hour care. Usually by the time you are discharged from the Endoscopy Unit, the full effects of Penthrox have worn off and you are able to go about your daily routine as normal. Avoid driving if you experience dizziness or drowsiness.
Following a colonoscopy, it is usually 2 or 3 days before your normal bowel movements commence. This is due to the bowel preparation used prior to your procedure
Common side effects from Penthrox may include:
- Dizziness or light-headedness
- Nausea or vomiting
- Headache
- Sweating
- Feeling sleepy or tired
- Abdominal discomfort
These symptoms may be relieved by taking ginger or peppermint tea/juice. A hot water bottle may help abdominal discomfort.
Move around, as this encourages wind to pass naturally. Drink plenty of fluids and avoid skipping meals. These symptoms may last for up to 8 hours. It is vital to seek medical advice if these symptoms persist or worsen.
If you experience any severe or persistent side effects, inform your healthcare provider immediately.
More severe complications are:
- Persistent/increasing abdominal pain
- Failure to pass wind
- Temperature above 38 Degrees
- Vomiting blood
These symptoms are rare but will need urgent medical attention.
This medicine can cause liver and kidney problems which can occur in the days or weeks after use. Although this is rare, it can be life-threatening so seek medical attention immediately and show the healthcare professional this card if you experience any of the symptoms listed below:
- Loss of appetite
- Nausea
- Vomiting
- Dark urine
- Reduced or excessive urination
- Pale stools
- Pain or sensitivity to touch in your right stomach area (below your ribs)
- Swelling of feet or lower legs
- Jaundice (yellowing of the skin and/or eyes)
Tell your healthcare professional about any side effects you get, including ones not listed in this card. You can also report side effects directly via www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects, you can help provide more information on the safety of this medicine.
You can get further information from:
Electronic Medicines Compendium (EMC)
https://penthrox.co.uk/patients/
If biopsies have been taken (this will be stated in your report), then you should contact your own G.P. or consultant's secretary 2 to 3 weeks post procedure. No histology results go to the Endoscopy Unit. Any other issues please use the contact details below.
Contact Details
Endoscopy Unit - Salford Royal Hospital
Telephone: 0161 206 5959 (Monday - Friday 8am - 8.30pm)
NHS Direct - 111 (24 Hours)
After 8:30pm and weekends please contact Majors Area, Emergency Dept on 0161 206 4848 and ask to speak to the doctor or the advanced nurse practitioner.
Date of Review: October 2025
Date of Next Review: October 2027
Ref No: PI_SU_2161 (NCA)