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What is Naltrexone for?


Naltrexone is used by specialist in the treatment of opiate and alcohol addiction. It blocks the euphoric effects of opiate drugs like morphine or heroin and helps you stay off these drugs.


How should I take Naltrexone?
 

Before taking naltrexone, tell your doctor if:
 

  • You are allergic to naltrexone or any of its ingredients (e.g. lactose)

  • You suffer from any other conditions, especially liver or kidney problems

  • You are taking or have used opiates within the past 7-10 days;

  • you take any other medicines, including any medicines that you may have bought without a prescription

  • You are pregnant (or planning pregnancy) or breastfeeding

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Your doctor will decide how much naltrexone is right for you to take. Do not give or share this medicine with others. Never take more than the prescribed dose. If you suspect that you or someone else has taken an overdose of naltrexone contact your doctor or go to the accident and emergency department of your local hospital. Always take the container with you, if possible, even if it is empty.


Do not use opiates while on naltrexone. Never try to overcome the effects of the medication by taking large doses of opiate drugs. Doing so could result in dangerous effects, including coma and death. Ask your doctor, pharmacist or nurse if you are not sure of anything.
 

Do I need to have any tests?


Your doctor will do a check up and blood tests before starting treatment to check if you are suitable for treatment. You will also be monitored regularly during treatment to make sure you can continue to receive naltrexone.


Can I stop taking Naltrexone if I feel better?
 

Your doctor will advise you about how long you should carry on taking your medication. After stopping naltrexone, you may be more sensitive to the effects of opiates and you could easily overdose. Do not stop taking the tablets unless told to do so by your doctor. Treatment with naltrexone is usually reviewed regularly.
 

What if I forget to take Naltrexone?
 

If you forget to take a tablet, take the missed dose as soon as possible. However, if it is almost time for the next dose, skip the missed dose and take the next dose at the usual time. Do not double the dose or take extra doses to make up. If you forget to take your medicine for more than a few days, call your doctor before taking any more medicine. Are there any side effects?
Naltrexone may cause side effects in some people, but they may vary from person to person. Many side effects wear off over time.
 

Known side effects include:
 

  • difficulty sleeping

  • abdominal pain

  • feeling sick or being sick

  • loss of appetite

  • diarrhoea and constipation

  • lack of energy

  • joint and muscle pain

  • headaches

  • dizziness

  • watery eyes

  • changes in sexual function

  • anxiety, nervousness and irritability

 

See your doctor as soon as possible if you develop problems which may need urgent attention:
 

  • feeling low in mood

  • thoughts of self-harm

  • tachycardia

  • yellowing of your skin or eyes

  • seeing, hearing or feeling things that are not real (hallucinations)

  • itching and flushing of skin or bruising

  • chest pain, shortness of breath

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Can I take other medicines?


Other medicines (especially opiates) may interact with naltrexone causing unwanted effects. Medicines you can buy over the counter without a prescription e.g. painkillers may interact with this medication.
Always ask your doctor or pharmacist before taking any other medicines.
 

Can I drive?
 

Naltrexone can make you feel tired, less alert and dizzy. If this happens, do not drive or work with machinery until you have discussed this with your doctor.
It is an offence to be in charge of a vehicle if unfit to drive through drink or drugs. Use of some medications which impair the ability to drive is also subject to specific rules in order to continue to drive. If unsure, please contact the DVLA for specific advice.
 

Can I drink alcohol?
 

Avoid drinking alcohol while taking naltrexone. The combined effects of naltrexone and alcohol can make you feel less alert.
 

Can I get pregnant or breast-feed?
 

Medicines can have harmful effects at any time during pregnancy. If you are pregnant, or are planning to get pregnant, you should seek advice from your doctor. You and your doctor or specialist will decide if the potential benefits of treatment outweigh the potential risks to the baby. Naltrexone may pass into breast milk. If you are breast-feeding, you should get your doctor’s advice.

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