Mysimba

Mysimba is a prescription weight-loss treatment that works by reducing your appetite. It is available to those with a BMI of 30 or more, or to those with a BMI of 27 and over and have medical complications exacerbated by their weight. This medication should be taken in combination with a low-calorie diet and regular exercise to ensure treatment success.

Mysimba contains two active ingredients, 8 mg of naltrexone and 90 mg of bupropion. The combination of the two alters the way the brain interprets hunger by reducing your appetite and increasing your energy expenditure. This means you can maintain a low-calorie diet without feeling cravings or hunger pains and the food you do eat is burnt off more easily during exercise. This is why it’s important to use this medication alongside a healthy diet and exercise plan.

You can only be prescribed this medication if you are 18 or over and have a BMI of 30 and above, or 27 and above if you have other medical conditions exacerbated by your weight such as diabetes, high blood pressure or high cholesterol.

You should not take this medication if you are pregnant or breastfeeding, or are allergic to any of the ingredients.This medication is also not recommended for those over the age of 75.

If you have any of the following preexisting conditions or take any of the following medication, you should also not take Mysimba:

• severe liver or kidney disease
• a brain tumour
• a condition that causes seizures (e.g epilepsy)
• uncontrolled high blood pressure
• a recent history of alcohol dependence or misuse
• a recent history of taking sedatives (benzodiazepines) for a mental health disorder
• a recent history of eating disorders (e.g anorexia)
• a recent history of opiate dependence or have taken opiates in the last 7 days (e.g methadone or codeine)
• take or have taken in the last 14 days any MAOIs (monoamine oxidase inhibitors) for depression or Parkinson’s disease

A full description of how to take Mysimba is available in the patient information leaflet, available at the bottom of this page or in the box with your medication. It’s important to follow these instructions to ensure treatment success.

The initial dosage of Mysimba is one tablet once a day. This is then steadily increased throughout the first weeks of treatment. The maximum recommended daily dose of Mysimba is two tablets twice a day.

Instructions are as follows:

• Week 1 - take one tablet once a day in the morning
• Week 2 - take two tablets a day, one in the morning and one in the evening
• Week 3 - take three tablets a day, two in the morning and one in the evening
• Week 4 and onwards - take four tablets a day, two in the morning and two in the evening

A course of treatment usually lasts 16 weeks, after which, one of our doctors will assess your progress. If you have not lost at least 5% of your starting weight after you have finished the first course, then it’s recommended that you discontinue treatment and seek other help.

Swallow the tablets whole, do not crush, split or break them. Avoid taking your evening dose close to bedtime. Avoid excessive alcohol consumption whilst taking Mysimba, as this is more likely to cause side effects.

If you miss a dose of Mysimba, skip the missed dose and take your next dose at your usual time. If you take more than your prescribed dose, you may be more likely to experience side effects.

Common side effects of Mysimba include:

• anxiety and/or irritability
• skin rash or itching
• dizziness (vertigo)
• feeling shaky (tremors)
• difficulty sleeping
• changes in your taste
• dry mouth
• fatigue
• ringing in the ears (tinnitus)
• irregular heartbeat
• hot flushes
• rise in blood pressure
• abdominal pain
• excessive sweating (hyperhidrosis)
• hair loss (alopecia)

Mysimba can cause more serious side effects such as fits (seizures) or severe depression. If you experience any serious side effects, please seek immediate medical attention.

For a full list of potential side effects, consult the patient information leaflet.

Some medications may increase the risk of fits if taken alongside Mysimba including:

• antidepressants
• oral steroids
• antimalarials
• quinolones (antibiotics)
• theophylline (asthma medication)
• antihistamines
• some medicines to lower blood sugar levels (e.g insulin)
• sedatives to treat depression or sleep disorders (e.g diazepam)

Other medications may interact with Mysimba and cause other side effects including medications for:

• high blood pressure
• an irregular heart rhythm
• cancer
• Parkinson’s disease
• heart disease or stroke
• HIV and AIDS
• epilepsy

Not all medications for these conditions will interact with Mysimba. For a comprehensive list of drug interactions, please refer to the patient information leaflet. If you’re not sure if you take any of these medications, please consult your GP before taking Mysimba.