What it is used for

Weight management in adults with obesity, or who are overweight with a weight-related health condition, alongside diet and activity

Read our guides:

Obesity

Off-label uses

Doctors sometimes prescribe a medicine for a condition it is not officially licensed for. This is called off-label use. It is legal and common when there is good evidence it helps, and your doctor should explain why they are suggesting it.

Naltrexone with bupropion is not commonly used off-label.

How it works

Bupropion acts on brain chemicals that control appetite, and naltrexone blocks a feedback signal that would otherwise limit this effect. Together they reduce hunger and food cravings.

Side effects

Like all medicines, Naltrexone with bupropion can cause side effects, although not everyone gets them. Many are mild and ease after the first few weeks.

Common side effects

feeling sick
constipation
headache
being sick
dizziness
trouble sleeping
dry mouth

Tell your doctor or pharmacist if these bother you or do not go away.

Serious side effects

These are rare. Call 111 or contact your doctor straight away if you get:

fits
raised blood pressure or a fast heartbeat
changes in mood, thoughts of harming yourself
signs of a serious allergic reaction or severe skin rash

Call 999 if you have signs of a serious allergic reaction, such as swelling of your lips, mouth, throat or tongue, or trouble breathing.

You can report any side effect to the Yellow Card scheme, run by the medicines regulator.

Stopping and withdrawal

Important safety information

It is not recommended by NICE for routine NHS use, so it is usually only available privately.
Not suitable if you have epilepsy, an eating disorder or uncontrolled high blood pressure, or take opioids.

Questions about your medicine?

A pharmacist can answer questions about your medicines for free, without an appointment. You can also ask your GP for a medication review. Check if you can get free prescriptions.