Mysimba dosage

Dr. Babak Ashrafi

Medically reviewed by

Dr Babak Ashrafi

Last reviewed: 30 Apr 2024

The starting dose of Mysimba is usually 1 tablet each morning. This is then gradually increased to 2 tablets, twice a day (4 tablets a day), after taking Mysimba for 4 weeks. Each tablet contains 8 mg of naltrexone hydrochloride and 90 mg of bupropion hydrochloride.

You can take up to 4 Mysimba tablets a day, but only if your doctor has prescribed you this dose. Your doctor will take you through how to take your medication and what doses to take during your treatment.

If you miss a dose, never take a double dose to make up for it. Skip the dose you missed and continue to take your medication as you normally would.


What is Mysimba?

The Mysimba appetite suppressant is a prescription medication. It can be used to help you lose weight if you’re overweight or obese. Mysimba tablets reduce your appetite, so you feel more full after less food, which makes you eat less. It does this by working on the part of your brain responsible for hunger.

Mysimba can help you safely and effectively lose weight, when taken alongside a healthy diet and regular exercise. Mysimba tablets are taken once or twice a day, depending on what you’ve been prescribed. A typical Mysimba result is a weight loss of at least 5% of your body weight after 4 months (16 weeks).

How does Mysimba work?

Mysimba tablets contain the active ingredients naltrexone hydrochloride and bupropion hydrochloride. These work on the areas of your brain that are responsible for food intake, hunger levels, and energy.

When you take Mysimba and reduce your calorie intake, you can eat less without feeling hungry. This makes it easier to make healthy lifestyle changes for safe and effective weight loss, such as snacking less.

How long does Mysimba take to work?

Mysimba tablets start working as soon as you take them, but you might not see the full effects of the medication until you’ve been taking it for a few weeks. This is because it needs some time to build up in your system, and in the first few weeks you’ll be slowly increasing your Mysimba dosage.

You should expect to lose about 5% of your starting weight after 4 months of taking Mysimba. If you don’t lose 5% of your starting weight, your doctor may suggest an alternative weight loss treatment. It’s also important to maintain a healthy diet and regular exercise to achieve your weight loss goals with Mysimba.

Mysimba ingredients – bupropion-naltrexone

Each Mysimba tablet contains 2 active ingredients: naltrexone hydrochloride (8mg) and bupropion hydrochloride (90mg). The combination of naltrexone/bupropion has been found to be an effective weight loss treatment.

Naltrexone binds to opioid receptors which causes you to feel fewer food cravings and reduces your appetite. Bupropion binds to norepinephrine and dopamine receptors, having an antidepressant effect that also helps reduce appetite.

Medically reviewed by:
Dr Babak Ashrafi Clinical Lead for Service Expansion
Accreditations: BSc, MBBS, MRCGP (2008)

Babak studied medicine at King’s College London and graduated in 2003, having also gained a bachelor’s degree in Physiology during his time there. He completed his general practice (GP) training in East London, where he worked for a number of years as a partner at a large inner-city GP practice. He completed the Royal College of GPs membership exam in 2007.

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Last reviewed: 30 Apr 2024

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