Mysimba (Naltrexone/Bupropion)

Form: Oral prolonged release tablet.

Mode of Action: The exact way that Mysimba works is not fully understood, but the two active substances, Naltrexone (a mu-opioid antagonist) and Bupropion (a weak inhibitor of neuronal dopamine and norepinephrine reuptake), act in two areas:

1. The hypothalamus to control food intake and energy balance.
2. The mesolimbic dopaminergic reward system controlling the pleasure associated with eating.

When both medicines are given together as a combination, their additive effect reduces appetite and the amount that customers eat. Coupled with an increased energy expenditure and calorie-controlled diet, this helps to reduce body weight.

Dose: Titrated up to two twice a day over 4 weeks. Start with one tablet daily increasing by one tablet each week until maintenance dose achieved.

Notes: Treatment should be discontinued after 16 weeks if customer has not lost at least 5% of their initial body weight.

Side effects include: Nausea, vomiting, diarrhoea, headache, anxiety, dizziness, fatigue, difficulty sleeping and irritability.

Mysimba is not currently available on the NHS and more information on this product can be found at the following link. EMC Mysimba