Naltrexone - oral

Patient Medicine Information
Why do I need this medicine?
Naltrexone is used as a supportive therapy in maintaining abstinence from alcohol.

This medicine may also be used to help overcome the addiction of those who are dependent on certain medicines such as opioids.

This medicine is meant to be taken as part of a management plan that should include patient education and counselling.
How do I take this medicine?
Take Naltrexone exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.

You may take this medicine with or without food. Try to take it at the same time each day.

It is important that you stop taking any opioid medicine for at least 7-10 days before starting on Naltrexone therapy. This medicine may cause withdrawal symptoms if you still have any trace of opioids in your body. Your doctor may perform tests to ensure opioid levels remain undetectable before you start with the treatment.
What should I do if I have forgotten to take this medicine?
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your normal dosing schedule.

DO NOT double a dose under any circumstances.

If you often forget to take your medicine, let your doctor and pharmacist know.
When should I not use this medicine?
Alert your doctor if you have the following conditions:

- severe liver disease
- severe kidney disease
- opioid dependent who failed to abstain from the addiction
- positive urine screening for opioids or failure to pass naloxone test
as this medicine may not be suitable for you.
What should I take note of while taking this medicine?
Inform your doctor if you have the following conditions:

- bleeding disorders
- liver disease
- kidney disease

Let your doctor know if you are pregnant or breastfeeding.

Keep your appointments with your doctor. Your doctor needs to monitor your condition and check your response to the medication regularly. Your doctor may also need to do routine blood tests (e.g. liver function tests) before you take Naltrexone and thereafter depending on your doctor’s advice.
What side effects could I experience?
Naltrexone may cause dizziness . If affected, do not drive or take part in any activity in which you need to be alert.

Other side effects include any of the following: nausea, vomiting, stomach cramps, diarrhoea, decreased appetite, joint and muscle pain, headache, difficulty sleeping, nervousness and weakness.

Some side effects may need immediate medical help. Alert your doctor quickly if you experience depression or thoughts of self-harm.

Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Can I take this with other medicines?
Inform your doctor and pharmacist if you are taking any of these medicines:

- medicines for mental illness e.g. thioridazine
- medicine for diabetes e.g. insulin

Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
What special dietary instructions should I follow?
Avoid alcohol.
How should I store this medicine?
Store in a cool, dry place away from the reach of children.

Medicines must not be used past the expiry date.
This information is independently developed by MIMS based on naltrexone - oral and is provided for your reference only. It is not a replacement for and should only be used in conjunction with full consultation with a licensed healthcare professional, the information provided by your pharmacist and/or the manufacturer of the medication. It may not contain all the available information you require and cannot substitute professional medical care, nor does it take into account all individual circumstances. Although great effort has been made to ensure content accuracy, we shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2021 MIMS. All rights reserved. Powered by
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