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Paraldehyde for treating prolonged seizures fact sheet

Paraldehyde for treating prolonged seizures

This fact sheet has been written for parents and carers about how to use this medicine in children. This information sometimes differs from that provided by the manufacturers, because their information is usually aimed at adult patients. Please read this information carefully and keep it somewhere safe so that you can read it again.

Paraldehyde is available as

Paraldehyde 100% 5mL Solution: Although manufactured as an injection, it is more commonly given rectally (into the bottom) mixed with olive oil.

It is also known by the Brand name

Phebra Paraldehyde 100% 5mL Solution ®
The supply of paraldehyde is only available through hospital pharmacies. Queensland Children’s Hospital Pharmacy stocks ‘Paraldehyde 100% 5mL Vials’ for patients in the hospital and also for outpatients.

If you need to give paraldehyde at home during an emergency, it is important that you have the correct supplies at home. This will be organised by your doctor or the clinical nurse from your treating team before you leave the hospital via the Central Resources Service (CRS).

Why is it important for my child to have this medicine?

Prolonged or clustered seizures sometimes develop into non-stop seizures, a condition called status epilepticus. Status epilepticus is a medical emergency. It is important to give your child the paraldehyde (as prescribed by your doctor) to stop prolonged seizing in epilepsy.

When should I give paraldehyde?

Paraldehyde is used to stop your child’s prolonged seizures. You should give the paraldehyde according to your child’s “Seizure Management Plan” developed by your child’s neurologist or doctor. This will include trying other medications first, as paraldehyde is given when other medications do not stop the seizures.

How much should I give?

Your child’s doctor or neurologist will calculate the dose of paraldehyde that is appropriate for your child based on your child’s weight. It is important that you follow the doctor’s/neurologist’s instructions regarding the dose. The amount to give will be written on the pharmacy label on the medicine.

How should I give it?

Paraldehyde is most often given into the bottom (rectally). Paraldehyde used rectally requires preparation before you give it. The instructions and equipment needed are included in the ‘Paraldehyde Administration Stepwise Guide’ below. At Queensland Children’s Hospital, we have clinical nurses and doctors that will teach you how to give the paraldehyde to your child.

When should the medicine start working and how will I know?

Paraldehyde takes 10-15 minutes to work. You will know the medication has started working when your child’s seizure slows and then stops. It is important you continue to follow your child’s Seizure Management Plan after you administer the paraldehyde including calling 000. Tell ambulance officers, emergency doctors, nurses and pharmacists that your child has had a dose of paraldehyde.

What if I give too much?

If you think you have given your child too much paraldehyde, contact the Queensland Poisons Information Centre on 13 11 26 and an ambulance on 000. It is important to know what dose the doctor has prescribed and how much paraldehyde you may have given your child.

Are there any possible side effects?

We use medicines to make our children better, but sometimes they have other effects that we don’t want (adverse effects or side effects).

Adverse effects you must do something about

  • If your child does not stop seizing, you must follow the emergency protocol outlined in your child’s Seizure Management Plan and call 000.

Other adverse effects you need to know about

  • Rash or irritation around the bottom. This can be soothed with nappy rash or barrier creams.
  • Paraldehyde-smelling breath for a few hours following treatment. This is the body’s normal response to this medication, as this is how paraldehyde is broken down in the body.
  • Drowsiness.

Long term effects

  • See Section on ‘Is there anything else I need to know about paraldehyde?’

Where should I keep this medicine?

Keep paraldehyde in the original container it came in from the pharmacy in a cool, dry place, away from heat and direct sunlight. Do not refrigerate paraldehyde. Check expiry dates regularly and do not use old vials that are beyond their use by date.

Paraldehyde affects plastic and rubber products. Once prepared in the syringe, it must be given immediately. Do not administer the paraldehyde if it has been in the syringe for longer than 10 minutes.

Make sure that children cannot see or reach the medicine and keep the medicine away from pets.

If the solution in the paraldehyde vial has become a brownish colour or has a stronger odour than usual dispose of the paraldehyde.

Helpful tips

  • Your child should have paraldehyde and the supplies to administer paraldehyde with them at all times in case of an emergency.
  • Consider forming an ‘emergency kit’ containing:
    • Your child’s Seizure Management Plan
    • Other medications your child may use for seizure management (instructions on the administration of these other medicines may also be useful)
    • Paraldehyde and supplies needed to administer
    • “Paraldehyde Administration Stepwise Guide”
  • Make sure anyone who looks after your child knows what to do if your child has a seizure and can access your child’s ‘emergency kit’.

Is there anything else I need to know about paraldehyde?

The manufacturer has improved the way that this medicine is tested. A previously undetectable impurity called crotonaldehyde has been found in the paraldehyde solution. It is virtually impossible to remove it from the paraldehyde, so the manufacturer looked carefully at the effects of crotonaldehyde. They determined that above certain levels in the body crotonaldehyde can be harmful, so they released the following warning:

This product contains crotonaldehyde, which is known to be *genotoxic and *carcinogenic. The recommended maximum life-time dose of paraldehyde is 30mL.

*Genotoxic: Damaging to the genetic information of a cell, causing it to mutate. This may lead to cancer.
*Carcinogenic: Having the potential to cause cancer.

About Crotonaldehyde

  • Crotonaldehyde is found in common, everyday foods and environments such as:
    • Air
    • Fruit and vegetables
    • Fish
    • Meat
    • Some alcohol (beer, whisky and wine)
    • Cigarette smoke

No-one has studied how crotonaldehyde from these sources affects humans.

  • The company based its recommendation on toxicity studies in animals. Whole-body effects from crotonaldehyde in humans taking paraldehyde by mouth (or other routes) have not been reported.
  • The recommended maximum life-time dose set by the company (30mL) has been chosen to reduce the risk of the bad effects of crotonaldehyde.
  • The recommended “safe” maximum life-time dose of paraldehyde (30mL in total), has much less crotonaldehyde than the toxic crotonaldehyde dose found in animal studies.
  • The risk from giving a patient more than the life-time dose of 30mL of paraldehyde is unknown, but everyone agrees that failing to treat prolonged seizures in a child is very high risk.
  • Talk to your child’s doctor about this risk and make a plan for ongoing therapy. If you agree to continue using paraldehyde to treat seizures in your child, you will be asked to consent to continue treatment. This consent will be documented in your child’s medical notes and may be required for each additional dose administered in hospital.
  • While doses of paraldehyde given in hospital will be recorded, it is important to keep your own notes of dates, times and quantities of paraldehyde given to your child to ensure that all doses given at different hospitals or facilities are recorded and added into the total amount. Cross check your records of the total amount given with the hospital at each admission. Discuss this further with your pharmacist or doctor.

Paraldehyde Administration Stepwise Guide


  • Paraldehyde 100% 5mL vial
  • Olive oil
  • Lubricant
  • Gloves (if desired)
  • Slip-tipped plastic syringe (large enough for total volume)
  • Blunt fill needle with filter (1.2mm X 40mm)
  • Sharps container
  • Paediatric urinary catheter female “Self-Cath®” (25cm Leur end)
  • Disposable container or medicine cup
  • Incontinence sheets or disposable towels/plastic for preparation area

Paraldehyde preparationPreparation:

Place the incontinence sheet or disposable towel/ plastic over the preparation area, wash hands thoroughly and apply gloves.

  1. Pour small volume of olive oil into a container or medicine cup.
  2. Remove syringe from packaging and attach the blunt fill needle.
  3. Take white top off ‘Paraldehyde 100% 5mL’ vial. Using blunt fill needle, draw up required dose of paraldehyde (in mL).
  4. Remove needle tip from syringe, store needle carefully until it can be disposed of into a sharps container.
  5. Using the syringe containing the paraldehyde, draw up a volume of olive oil that is equal to the paraldehyde dose.
  6. Invert syringe to mix the solution and draw up an additional 2mL of air (air chaser). Attach the catheter to the syringe.
  7. Lubricate the end of the catheter and ensure air in syringe is behind the solution (so the air follows the solution when given).
  8. With the child lying on their side in the recovery position, insert catheter into child’s rectum and administer the syringe contents.
  9. Hold child’s buttocks together immediately and continue for 2 minutes after administration. Monitor for response. Wash hands thoroughly.

If the paraldehyde comes into contact with the eyes or skin, wash with running water for 10 minutes.


  • Always keep a copy of your child’s Seizure Management Plan and all medicines with you and your child.
  • Talk to your doctor and provide informed consent regarding the use of paraldehyde in your child at Queensland Children’s Hospital.
  • Track the life-time dose of paraldehyde given to your child.
  • Ask for education about the preparation and administration of paraldehyde from the clinical staff at Queensland Children’s Hospital.
  • Know how to obtain paraldehyde and all of the supplies needed to administer it rectally.

As mentioned, it is important all doses of paraldehyde given to your child are documented in your child’s medical records at the hospital and your personal records. Paraldehyde doses given to your child must be added up to track the amount they have received over their life.

General advice about medicines

  • Only give this medicine to your child. Never give it to anyone else, even if their condition appears to be the same, as this could do harm.
  • If you think someone else may have taken the medicine by accident, contact your doctor straight away or contact the Queensland Poisons Information Centre on 13 11 26.
  • Make sure that you always have enough medicine. Order a new prescription at least 2 weeks before you will run out.
  • Make sure that the medicine you have at home has not reached the ‘best before’ or ‘use by’ date on the packaging. Give old medicines to your pharmacist to dispose of.
  • Your doctor, pharmacist or nurse will be able to give you more information about paraldehyde and about other medicines used to treat prolonged seizures.

Who to contact for more information

Level 2, Queensland Children’s Hospital
501 Stanley Street, South Brisbane, QLD 4101
t: 07 3068 1901

In an emergency, always call 000.

Queensland Poisons Information Centre 13 11 26.

Developed by Pharmacy Department, Queensland Children’s Hospital. Updated: April 2017.

For details on any other sources used to create this leaflet, please contact us via

We take great care to make sure that the information in this leaflet is correct and up-to-date. However, medicines can be used in different ways for different patients. It is important that you ask the advice of your neurologist or hospital pharmacist if you are not sure about something.

This leaflet is about the use of these medicines in Australia, and may not apply to other countries. Children’s Health Queensland Hospital and Health Service cannot be held responsible for the accuracy of information, omissions of information, or any actions that may be taken as a consequence of reading this leaflet.