Mysimba

Weight gain is very common in women going through menopause. Many women also struggle to lose weight. One of the reasons for this is that your metabolic rate slows down with menopause. Weight loss medications, such as Mysimba, are used to treat seriously overweight and obese people. You will only be considered for this treatment if you have:

• a BMI of 30 kg/m² or greater (obesity), or
• a BMI of 27 kg/m² and less than 30 kg/m² (overweight) and weight-related health problems (such as diabetes, high blood pressure, high cholesterol or obstructive sleep apnoea).

Mysimba contains two active ingredients, naltrexone hydrochloride and bupropion hydrochloride. These ingredients act on the area of the brain involved in controlling appetite. By reducing appetite, Mysimba makes it easier to stick to a weight loss plan.

It is important to note that Mysimba is no miracle cure, but it can support your weight loss efforts if used with a reduced-calorie diet and increased physical activity. If after 16 weeks on Mysimba you have not lost 5% of your body weight, the treatment may be deemed unsatisfactory and your prescription may be discontinued.

Always take this medicine exactly as your doctor has told you. Check with your doctor or pharmacist if you are not sure.

The initial dose is usually:

• one tablet (8 mg naltrexone hydrochloride / 90 mg bupropion hydrochloride) once a day in the morning. 

The dose will be gradually adapted as follows:

• Week 1: one tablet once a day in the morning.
• Week 2: two tablets every day, one in the morning and one in the evening.
• Week 3: three tablets every day, two in the morning and one in the evening.
• Week 4 and onward: four tablets every day, two in the morning and two in the evening.

The maximum recommended daily dose of Mysimba is four tablets (two tablets taken twice a day).

This medicine is for oral use. Swallow your tablets whole. Do not cut them, chew them or crush them. The tablets should preferably be taken with food.

After 16 weeks and each year after your treatment initiation, your doctor will evaluate whether you

should continue to take Mysimba.

Driving/alcohol

Mysimba can cause dizziness. Do not drive, use any tools or machines, or perform dangerous activities until you know how this medicine affects you.

Excessive use of alcohol while being treated with Mysimba might increase the risk for fits (seizures),

mental disorder events or might reduce alcohol tolerance. Your doctor may suggest you do not drink alcohol while you are taking Mysimba, or try to drink as little as possible. If you do drink a lot now, do not just stop suddenly, because that may put you at risk of having a fit.

If you take more or less Mysimba than you should/stop taking Mysimba

If you take too many tablets, you may be more likely to have side effects. Do not delay, contact your doctor or your nearest hospital emergency department immediately.

If you forget to take a dose of Mysimba, then skip the missed dose and take your next dose at the next usual time. Do not take a double dose to make up for a forgotten dose.

You may need to take Mysimba for at least 16 weeks to have its full effect. Do not stop taking Mysimba without talking to your doctor first.

Mysimba is not suitable for everyone. Do not take Mysimba if:

• You are allergic to any of the ingredients in this medicine (see section ‘What Mysimba contains').
• You have an abnormally high blood pressure (hypertension) that is not controlled using a
• You have a condition that causes fits (seizures) or if you have a history of fits.
• You have a brain tumour.
• You are usually a heavy drinker and you have just stopped drinking alcohol, or are going to stop while you are taking Mysimba.
• You have recently stopped taking sedatives or medicines to treat anxiety (especially
• You have or have had a bipolar disorder (extreme mood swings).
• You are using any other medicines which contain bupropion or naltrexone.
• You have an eating disorder or had one in the past (for example, bulimia or anorexia nervosa).
• You are currently dependent on chronic opiates or opiate agonists (for example methadone), or you are going through acute withdrawal (cold turkey).
• You are taking medicines for depression or Parkinson’s disease called monoamine oxidase
• You have severe liver disease.
• You have end-stage kidney disease.

This medicine is not suitable for use in children.

When should this medicine be used with caution?
Talk to your doctor or pharmacist before taking this medicine if:

• You feel depressed, contemplate suicide, have a history of attempting suicide or any other mental health problems.
• You are taking medicines that may increase the risk of fits (see 'Other medicines and Mysimba').
• You have high blood pressure before taking Mysimba.
• You have uncontrolled coronary artery disease (a heart disease caused by poor blood flow in the blood vessels of the heart) with symptoms such as angina (characterised by chest pain) or a recent heart attack.
• You already have or have had a condition affecting the circulation of blood in the brain
• You have any liver or kidney problems before you start Mysimba.
• You have a history of mania (feeling elated or over-excited, which causes unusual behaviour).
• You are 65 years or older.

Pregnancy and breastfeeding

Mysimba should not be used during pregnancy or while breastfeeding.

Other medicines and Mysimba

Mysimba may interact with other medicines.

Do NOT take Mysimba with:

• Monoamine oxidase inhibitors. You must stop taking these medicines for at least 14 days before starting Mysimba.
• Opiates and opiate-containing medicines for example to treat cough and cold, opiate addiction, pain, and diarrhoea. You must have stopped taking any opiate medicines at least 7-10 days before starting Mysimba.

Tell your doctor if you are taking any of the following medicines, as your doctor will closely monitor you for side effects:

• Medicines that may, when used alone or in combination with naltrexone/bupropion, increase the risk of fits.
• Medicines for depression and other mental health problems.
• Some medicines used to treat high blood pressure.
• Some medicines used to treat irregular heart rhythm.
• Some medicines used to treat cancer.
• Some medicines for Parkinson’s disease.
• Ticlopidine or clopidogrel, mainly used in the treatment of heart disease or stroke.
• Medicines used in the treatment of HIV infection and AIDS.
• Medicines used to treat epilepsy.

For a complete list of warnings, see the package leaflet.

Like all medicines, this medicine can cause side effects, although not everybody gets them.

Serious side effects

• Fits (seizures). Rare - may affect up to 1 in 1,000 people taking Mysimba with a risk of having a fit.

Very common side effects (may affect more than 1 in 10 people)

• Nausea and/or vomiting.
• Stomach pain.
• Constipation.
• Headache.
• Difficulty sleeping (make sure you do not take Mysimba near to bedtime).
• Anxiety.
• Pain in the joints or in the muscles.

Common side effects (may affect up to 1 in 10 people)

• Low number of white blood cells.
• Dizziness.
• Feeling shaky (tremor).
• Feeling jittery, irritability.
• Mood swings.
• Cold tremors, fever.
• Loss of appetite, diarrhoea.
• Changes in the taste of food (dysgeusia), dry mouth, toothache.
• Difficulty concentrating.
• Feeling of tiredness (fatigue) and sleepiness, drowsiness or lack of energy (lethargy).
• Ringing in the ears (tinnitus).
• Rapid or irregular heartbeat.

For a complete list of side effects, see the package leaflet. Consult a doctor if you experience any side effects.

The active substances are:

• Naltrexone hydrochloride and bupropion hydrochloride.
  Each tablet contains 8 milligrams of naltrexone hydrochloride, equivalent to 7.2 milligrams of naltrexone, and 90 milligrams of bupropion hydrochloride, equivalent to 78 milligrams of bupropion.

The other ingredients are:

• Tablet core: microcrystalline cellulose, hydroxypropyl cellulose, lactose anhydrous, lactose
• Film-coating: poly(vinyl alcohol), titanium dioxide (E171), macrogol (3350), talc and indigo carmine aluminium lake (E132).