Opioid-induced constipation information sheet

Contact details

Pharmacy, Sydney Children's Hospital, Randwick 

Outpatient prescription orders: SCHN-SCHPharmacy@health.nsw.gov.au 

Phone: (02) 9382 1368 

Introduction

Opioids relieve severe pain but cause constipation as a side effect.  

What are opioids

Opioids are pain-relief medications used for strong pain when paracetamol and ibuprofen are not enough. 

Common opioids your child may be treated with include oxycodone, morphine, fentanyl, and tapentadol. 

Typically used short-term, side effects like opioid-induced constipation last only while your child is on the medication.

Constipation

What is constipation

Constipation is when your child is unable to empty their bowels (do a poo) as often or as easily as they normally would. 

How often should my child open their bowels

Normal bowel emptying can be different for everyone, ranging from 3 times a day to 3 times a week. 

Constipation is when your child’s bowel motions are less frequent/harder to pass than their usual. 

How do opioids cause constipation

Opioids can cause constipation by slowing down the movement of poo through your child’s intestines. 

More water is pulled out of the poo, and this makes it hard, dry and difficult to pass. 

The more opioids your child is given the more likely they are to have constipation as a side effect.  

Treating opioid-induced constipation

Step 1: Diet and Fluids

  • Drinking enough water to satisfy thirst and keep urine ‘light coloured’. 
  • If your child needs to poo, don’t let them hold. 
  • Avoid drinks with caffeine in them e.g. fizzy drinks, coffee 
  • Eat more fibre e.g. apples, pears, prunes as well as legumes like lentils and kidney beans 

Step 2: Laxatives

If drinking more water and eating more fibre does not work, try using a laxative that can be bought from your local pharmacy. You do not need a prescription to buy these medications. 

Before choosing the right laxative for your child, consider their age, if they can swallow tables, what flavour they prefer and how long your child will need the laxative for. 

Note: Multiple laxatives can be used at the same time as long as they are not the same type. 

 

Laxative types

Osmotic laxatives

Recommendations based on age: 

1 month – 3 years old 

Macrogol Powder 3350 Sachets (Osmolax®)  
2-3 years = HALF a sachet (8.5g), mixed with at least 10mL of water daily (Maximum 1 full sachet a day) 
Flavour free

3 years – 6 years old 

Macrogol Powder 3350 Sachets (Osmolax®) 
Half a sachet mixed with at least 10mL of water (8.5g) daily (Maximum 1 full sachet a day) 
Flavour free 

6 years - 12 years old 

Macrogol Powder 3350 Sachets (Osmolax®) 
1 sachet (17g) mixed with at least 10mL of water daily (Maximum 1.5 sachets a day) 
Flavour free 

12+ years old 

Macrogol Powder 3350 Sachets (Osmolax®) 
1 sachet (17g) mixed with at least 10mL of water daily (Maximum 2 sachets a day) 
Flavour free 

 

Note: Osmotic laxatives take 1-2 days to work and can be used long term 

Stool softeners

Recommendations based on age: 

1 month - 3 years old

Poloxomer (Coloxyl Infant Drops®) 

Flavours: Caramel and chocolate  

  • under 6 months = 0.3mL 3 times a day
  • 6-18 months = 0.5mL 3 times a day
  • 18 months - 3 years = 0.8mL 3 times a day 

3 years - 6 years old

Docusate 50mg tablet (Coloxyl®) 
1 tablet once a day  
Tablet can be crushed and mixed with water or in yoghurt/apple puree 

6 years - 12 years old 

Docusate 50mg tablets (Coloxyl®) 
1-3 tablets a day (Maximum 3 tablets a day)  
Tablet can be crushed and mixed with water or with yoghurt/apple puree 

12+ years old 

Docusate 50mg tablets (Coloxyl®) 
1-3 tablets a day (Maximum 9 tablets a day)  
Tablet can be crushed and mixed with water or with yoghurt/apple puree 
 

Note: Stool softeners take 1-2 days to work and can be used long term 

Stimulant laxatives

Recommendations based on age: 

3 years - 6 years old

Senna 7.5mg tablets (Senokot®)  
Half to 1 tablet at bedtime 
Tablets can be crushed and mixed with apple puree/yoghurt 
Flavour of crushed tablet is unpleasant 

OR

Senna 12mg Chocolate Squares (Laxettes with sennosides)  
Half a square at bedtime 
Flavour Chocolate (squares are chewable) 

6 years - 12 years old 

Senna 7.5mg tablets (Senokot)  
1-2 tablets at bedtime 
Tablets can be crushed and mixed with apple puree/yoghurt 
Flavour of crushed tablet is unpleasant 

OR

Senna 12mg Chocolate Squares (Laxettes with sennosides)  
1 square at bedtime 
Flavour Chocolate (squares are chewable) 

12+ years old 

Senna 7.5mg tablets (Senokot®) 
1- 4 tablets at bedtime 
Tablets can be crushed and mixed with apple puree/yoghurt 
Flavour of crushed tablet is unpleasant 

OR

Senna 12mg Chocolate Squares (Laxettes with sennosides)  
1 - 2 squares at bedtime 
Flavour Chocolate (squares are chewable) 

 

Note: Stimulant laxatives take 6-12 hours to work and should only be used in the short term (1-2 weeks) 

Disclaimer

This information sheet is a guide only, intended for use by parents and carers only. Medication should only be given to children by a responsible adult when required and as directed by the doctor or pharmacist.  

Medication should be stored safely and out of reach and sight of children.  

If your child’s symptoms do not improve with medication see your local health care professional (a pharmacist or a doctor) for more advice.