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Your child has to use the medicine called fentanyl (say: FEN-ta-nil). This information sheet explains what fentanyl does, how to give it, and what side effects or problems your child may have when he uses this medicine.

Fentanyl is a medicine used to relieve pain

You may hear fentanyl being called by its brand name Duragesic®. Fentanyl comes as a patch or an injection.

Before giving fentanyl to your child…

Talk to your child’s doctor if your child is:

  • allergic to fentanyl or any other medications
  • less than two years old
  • has never taken pain medication that contains codeine​, morphine​, hydromorphone, oxycodone, or any other opioid drugs

Talk with your child’s doctor or pharmacist if your child has any of the following conditions. Precautions may need to be taken with this medicine if your child has:

  • had a recent head injury
  • severe kidney or liver disease
  • blockage of the intestines
  • severe lung disease
  • heart disease
  • a fever

How should you give your child fentanyl?

  • Do not use a patch if it is damaged or cut.
  • Wash your hands before and after applying the patch.
  • Apply the patch to your child’s upper back. In older children the patch can be applied on the chest, upper leg, or upper arm. Do not apply to broken or irritated skin.
  • Remove the patch from the pouch and then remove the protective liner. Apply the sticky side of the patch to the skin and press firmly with the palm of the hand for 30 seconds. Apply the patch so that it lies flat on the skin.

The patch can be worn for 72 hours

  • When the patch is finished, remove it from the skin and fold in half so that it sticks to itself, and flush down the toilet
  • Use a different part of the body, such as back, chest, arm, or leg, each time you apply a new patch.
  • If the patch falls off replace with a new one. Let your child’s doctor know if this happens.
  • Do not apply more than one patch at a time.

What should you do if your child misses a dose of fentanyl?

  • If you forget to change the patch after 72 hours, remove it as soon as you remember and apply a new patch.
  • Do not apply two patches to make up for the missed one.

What are the possible side effects of fentanyl?

Your child may have some of these side effects while he or she is on fentanyl. Check with your child’s doctor if your child continues to have any of these side effects, and they do not go away, or they bother your child:

  • Irritation around the area where the patch is applied.
  • Feeling sleepy or having difficulty concentrating. Have your child avoid activities that require alertness until you see how the medicine affects him or her.
  • Dizziness. Have your child rise slowly over several minutes from a sitting or lying position. Your child should be extra careful climbing stairs.
  • Nausea or vomiting (throwing up). Eating small frequent meals may help.
  • Dry mouth. Chewing on ice chips and sugar-free candy may help.
  • Constipation. More liquids, regular exercise, or an increase in fiber intake may help. Talk to your doctor or pharmacist about a stool softener or laxative.

Most of the following side effects are not common, but they may be a sign of a serious problem. Call your child’s doctor right away or take your child to Emergency if your child has any of these side effects:

  • difficulty breathing, slow breathing, or shallow breathing
  • wheezing; chest tightness; swelling of the face, lips, throat, or tongue
  • seizures
  • fainting or severe dizziness
  • unusual changes in behaviour
  • extreme nervousness and excitability
  • extreme weakness or tiredness
  • severe nausea and vomiting (throwing up)
  • severe constipation
  • no improvement in pain or worsening of pain

What safety measures should you take when your child is using fentanyl? 

  • At high temperatures, more fentanyl can be released from the patch. Avoid exposing the area with the patch to external heat sources such as heating pads, electric blankets, saunas, sunbathing, hot water bottles, and heat lamps. Let the doctor know if your child develops a fever. The dose of the patch may need to be adjusted. 
  • Clean the skin where the patch will be applied with water only. Do not use soaps, oils, lotions, or alcohol.
  • This medicine may cause your child to be less alert. Watch your child’s activities closely until you see how fentanyl affects him. You may also have your child avoid tasks that require alertness, such as riding a bicycle or rollerblading.
  • This medicine should be thrown out when your child no longer needs it or if the medicine becomes outdated. Remove the patch from the pouch, remove liner, and fold in half. Flush the folded patch down the toilet or put it in a sealed container away from children and pets.

It is important to tell your doctor or pharmacist if your child takes any other medicines, such as prescription, over the counter, or herbal. In some cases the dose of fentanyl or other medicines may need to be adjusted. These medicines may include:

  • muscle relaxants
  • antihistamines
  • sleeping or anxiety medicines, such as benzodiazepines
  • certain antibiotics or antifungals, such as clarithromycin​, ketoconazole, and itraconazole,
  • other pain medicines
  • certain antiviral medications such as ritonavir and nelfinavir

What other important information should you know about fentanyl?

Keep a list of medicines your child is on and take the list to the doctor or pharmacist.

Do not share your child’s medicine with others. Do not give anyone else’s medicine to your child.

Do not stop fentanyl suddenly or adjust the dose of fentanyl without speaking to your child’s doctor first. The doctor may want to slowly wean your child off the medicine to prevent withdrawal effects.

Keep fentanyl at room temperature in a cool, dry place away from sunlight. Do not store it in the bathroom or kitchen. Keep the patch in the protective pouch until you are ready to use it.

Keep fentanyl out of your child’s reach and locked up in a safe place. If your child receives too much fentanyl, call the Ontario Poison Centre at one of these numbers. These calls are free.

  • Call 416-813-5900 if you live in Toronto.
  • Call 1-800-268-9017 if you live elsewhere in Ontario.
  • If you live outside of Ontario, call your local Poison Information Centre.

Disclaimer: The information in this Family Med-Aid is accurate at the time of printing. It provides a summary of information about fentanyl and does not contain all possible information about this medicine. Not all side effects are listed. If you have any questions or want more information about fentanyl, speak to your health care provider.

Jennifer Drynan-Arsenault, BSc, RPh, ACPR