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Gabapentin (gab-a-pen-tin)

Gabapentin is commonly used in children and young people for the following reasons:

  • prevention of some seizures,
  • reduce pain from nerve damage (neuropathic pain) and given prior to certain operations for pain relief,
  • reduce general muscle tightness, twisting movements or abnormal postures due to involuntary muscle contractions (dystonia). It can improve general muscle comfort for these patients.

It acts in the brain and on nerves to slow the messaging to muscles and nerves and can be used for other conditions.

Gabapentin is known by different brand names. (e.g. Neurontin®, Gapentin®, Gabacor®, Nupentin®). It is available on prescription as 100 mg, 300 mg and 400 mg capsules (all contain lactose) and 600 mg and 800 mg tablets.

While using this medicine – Remember

  • Gabapentin may cause drowsiness, which is increased when used with other medicines that cause drowsiness.
  • Any dose change must be guided by your doctor. Gabapentin should be decreased slowly over at least a week. Stopping gabapentin suddenly can cause withdrawal symptoms (anxiety, difficulty sleeping, nausea, pain, sweating or seizures). This is because the body becomes used to having gabapentin on board.
  • Watch for unusual changes in mood or behaviour including aggression, irritability or agitation, negative feelings or worsening mental health with thoughts/talk of self-harm – Tell your doctor immediately if these changes occur.
  • Talk to your doctor if your child or young person is pregnant or planning to become pregnant.

Giving my child gabapentin

The person prescribing gabapentin will work out the amount (the dose) that is best for your child. It may take a few days or sometimes weeks to see the effects. Gabapentin is started at a low dose and increased slowly. They will ask how well the medicine is working and may change the dose and time of the day you give it to get the best effect. If you think the dose is not right or the medicine is not working, talk to your prescriber.

When and how should I give gabapentin?

  • Gabapentin is usually started once a day for a few days, at night as it causes sleepiness, and then increased to a maximum of three times a day. Usually it is given first thing in the morning, early afternoon and at bedtime, with doses at least 4 hours apart.
  • Try to give the medicine at about the same times each day. This will help you remember.
  • Gabapentin can be given with or without food.
  • It has a bitter taste when tablets are crushed, or capsules opened. There is no liquid product available. To disguise the taste, mix the capsule contents or crushed tablet (tablet is hard to crush) in a small amount of apple puree, chocolate pudding, water or orange juice. Talk to your pharmacist. The capsule contents or finely crushed tablet can be given down feeding tubes mixed in 10 mL water, flushing the line well before and after.

What to do if a dose is missed or my child vomits

If your child is only having one dose a day and it is missed, you can still give the dose if there are 12 hours before the next normal dose. Do not wake your child to give a missed dose.
If you usually give it twice a day and a dose is missed, give the missed dose if you remember within 4 hours otherwise skip the dose.
If you give it three times a day, do not give the missed dose. Just give the next dose as usual.

Never give a double dose of the medicine to catch up a missed dose. If several doses in a row are missed, contact your doctor for advice.

If your child vomits within 30 minutes after having a dose, you can repeat the dose. If your child continues to vomit, contact your doctor or call 13HEALTH. If they vomit more than 30 minutes after the dose, do not repeat the dose.

What to do if I give too much gabapentin

If you think your child has had too much gabapentin call the Poisons Information Centre on 13 11 26 even if your child shows no effects. In an emergency, call 000 for an Ambulance. Have the medicine packaging with you, even if it is empty, as this information will be useful.

What about using other medicines/substances with gabapentin?

Tell your doctor or pharmacist about any other medicines or products your child takes before starting gabapentin. These include prescription, over the counter medicines, vitamins, supplements, herbal or complementary medicines that you buy from a pharmacy, supermarket, health food shop or online. While your child is on gabapentin, check with your doctor or pharmacist before starting anything new especially medicines that cause drowsiness (e.g. medicines to help with sleep, sedating antihistamines, some cough medicines and strong pain relief medicines).

You can give your child paracetamol (e.g. Panadol®, Dymadon®) and anti-inflammatories like ibuprofen (e.g. Hedafen®, Nurofen®) with gabapentin for pain and fever, unless your doctor has told you not to.

Antacids reduce the absorption of gabapentin. If your child is taking an antacid for indigestion (e.g. Mylanta®, Gaviscon®) give the gabapentin at least 2 hours after the antacids.

Alcohol or illicit drugs should not be consumed while taking gabapentin.

Possible side effects – what other effects can occur?

Side effects you must do something about (these are uncommon, rare side effects)

Call 000 for an ambulance if your child is:

  • Very sleepy or difficult to wake up
  • Showing signs of a severe allergic reaction like swelling of the lips, mouth or throat, rash, itching or hives, difficulty breathing
  • Seizures or more frequent/severe seizures than normal
  • Other serious reactions – skin rash, fever, swollen glands, flu like symptoms, muscle aches, weakness, yellowing of skin or eyes (jaundice)

Contact your doctor as soon as possible if you notice any of the following

  • Changes in behaviour, emotions or mood including
    • Restlessness, irritability, or aggression
    • Anxiety, increased nervousness, hyperactive, or poor sleep
    • Abnormal thoughts/talk about harming themselves (this is a very rare side effect)
  • Signs of frequent infections such as fever, severe chills, sore throat or mouth ulcers
  • New problems with balance, or feeling shaky or unsteady
  • Double or blurred vision, unwanted eye movements

Other side effects you need to know about

Some side effects go away with time or after the dose has been changed. Speak to your doctor if you are worried about any of the following or if they continue.

  • Sleepiness/drowsiness: Your child may feel sleepy, tired or sluggish. This can last for a few hours after a dose and should wear off over time.
  • Dizziness: Care must be taken when riding bikes/scooters, climbing or activities needing balance. For older children, avoid driving or operating machinery due to dizziness and drowsiness.
  • Forgetfulness, trouble with memory or concentration.
  • Weight gain: Your child may be hungrier than usual with an increased appetite and may gain weight. Try encouraging healthy eating, appropriate portion sizes and exercise.
  • Headaches: Your child may have headaches; these should be mild and wear off.
  • Stomach upset: Your child may feel sick (nausea), vomit or have a stomach ache. Give gabapentin with food.
  • Dry mouth should wear off. Regular sips of water, sucking on ice/ frozen pineapple chunks or sugar-free sweets or using saliva substitutes can be helpful.
  • Swelling of hands, feet, ankles or lower legs should lessen over time.

General medicine advice

Only give this medicine to your child who was prescribed it. Never give it to anyone else, even if their condition appears to be the same, as this could do harm. Contact Poisons Information Centre on 13 11 26 if another person takes this medicine.  

Store gabapentin in a cupboard, a cool dry place away from heat, direct sunlight and moisture, below 25 oC. It does not need to be kept in the fridge.

Store all medicines in the container/box it came in, out of sight and where children cannot reach them.

Dispose of expired medicines or medicines you no longer need by taking them to your pharmacy.

For more information

This fact sheet is about using this medicine in children and young people. Some information may be different from the manufacturer’s Consumer Medicine Information (CMI). The manufacturer’s CMI is found at NPS MedicineWise. These should be read together.

– Talk to your doctor, nurse or pharmacist

Download Gabapentin dosing plan

Contact us

In an emergency, always contact 000 for immediate assistance

Pharmacy Department
Level 2, Queensland Children’s Hospital 501 Stanley Street, South Brisbane 4101
t: 07 3068 1901 (9am – 5pm daily)

Disclaimer

Document ID: CHQ-MFS-75704. Updated: 06/09/2021 v1.0. Endorsed by Queensland Children’s Hospital Medication Safety Committee with input from parents and carers. Contact CHQMedicationSafety@health.qld.gov.au for sources used to create this Fact Sheet.

We take great care to make sure the information in this Fact Sheet is correct, up-to-date and reflects current use in Australia. However, medicines can be used in different ways for different patients. It is important to ask the advice of your doctor or pharmacist if you are not sure about something. This Fact Sheet is to be used as an aid, rather than a substitute for a discussion with your doctor or pharmacist. Children’s Health Queensland Hospital and Health Service accepts no responsibility for any inaccuracies, omissions, reliance placed, or the success of any treatment regimens detailed in this Fact Sheet.

CHQ