This page has been reviewed by
Dr. Nicolette Lammers.
Possible side effects of Mysimba
Proper use and dosing of Mysimba are important. Always use this medicine exactly as agreed with your doctor. On this page you will find information on possible Mysimba side effects from the patient information leaflet, along with guidance on what to do if warning signs occur. This information does not replace individualized medical advice. If you experience acute, severe symptoms, seek medical help immediately. If you notice any side effects, talk to your doctor or pharmacist. Like all medicines, this medicine can cause side effects, although not everybody gets them.Serious side effects
Inform your doctor or pharmacist immediately if you notice any of the following serious side effects:- Suicidal thoughts or depression The frequency of the side effects suicide attempts, suicidal behavior, suicidal thoughts, and depression is not known and cannot be estimated from the available data in people taking Mysimba. There have been reports of depression, suicidal thoughts, and suicide attempts during treatment with Mysimba. If you think about harming yourself, or have other concerning thoughts, or if you feel depressed and notice that you are getting worse or you develop new symptoms, contact your doctor immediately or go to a hospital right away.
- Seizures (epileptic seizures) Rare: may affect up to 1 in 1,000 people who take Mysimba and are at risk of seizures. Symptoms of seizures include, for example, convulsions and usually loss of consciousness. After a seizure, a person may be confused and may not remember what happened. Seizures are more likely if you take too much, if you take certain other medicines, or if you have an increased risk of seizures (see Section 2).
- Erythema multiforme and Stevens-Johnson syndrome Not known: frequency cannot be estimated from the available data in people taking Mysimba. Erythema multiforme is a serious skin condition that can affect the mouth and other parts of the body. It involves red, usually itchy spots starting on the limbs. Stevens-Johnson syndrome is a rare skin condition in which severe blistering and bleeding occur on the lips, eyes, mouth, nose, and genitals.
- Rhabdomyolysis Not known: frequency cannot be estimated from the available data in people taking Mysimba. Rhabdomyolysis is an abnormal breakdown of muscle tissue that can lead to kidney problems. Symptoms include severe muscle cramps, muscle pain, or muscle weakness.
- Lupus rash or worsening of lupus symptoms Not known: frequency cannot be estimated from the available data in people taking Mysimba. Lupus is an immune system disorder that affects the skin and other organs. If you develop lupus flare-ups, rashes, or lesions (especially in areas exposed to sunlight) while taking Mysimba, contact your doctor immediately, as treatment may need to be stopped.
Other possible side effects include
Very common (may affect more than 1 in 10 people)
- Nausea, vomiting
- Constipation
- Headache
Common (may affect up to 1 in 10 people)
- Anxiety
- Dizziness or vertigo
- Feeling “shaky” (tremor)
- Sleep disturbances (make sure you do not take Mysimba shortly before bedtime)
- Altered sense of taste (taste disturbance), dry mouth
- Difficulty concentrating
- Fatigue and sleepiness, drowsiness or lack of energy (lethargy)
- Ringing in the ears (tinnitus)
- Fast or irregular heartbeat
- Hot flashes
- High blood pressure
- Upper abdominal pain
- Abdominal pain
- Excessive sweating (hyperhidrosis)
- Rash, itching (pruritus)
- Hair loss (alopecia)
- Irritability
- Feeling scattered
Uncommon (may affect up to 1 in 100 people)
- Hives (urticaria)
- Hypersensitivity
- Unusual dreams
- Nervousness, feeling “spaced out,” tension, restlessness, mood swings
- Shaking of the head or a limb that worsens when you try to perform a specific action (intention tremor)
- Balance disorders
- Memory loss (amnesia)
- Tingling or numbness of the hands or feet
- Motion sickness
- Belching
- Abdominal discomfort
- Digestive problems
- Inflammation of the gallbladder (cholecystitis)
- Increased creatinine in the blood (a sign of loss of kidney function)
- Increased liver enzymes and bilirubin levels, liver disorders
- Problems getting or maintaining an erection
- Feeling unwell, weakness (asthenia)
- Thirst, feeling hot
- Chest pain
- Increased appetite, weight gain
Rare (may affect up to 1 in 1,000 people)
- Low number of certain white blood cells (decreased lymphocyte count)
- Decreased hematocrit (indicating a reduction in red blood cell volume)
- Swelling of the eyelids, face, lips, tongue, or throat, which can cause breathing problems (angioedema)
- Excessive loss of body fluid (dehydration)
- Hallucinations
- Fainting, loss of consciousness, nearly fainting (presyncope)
- Seizures
- Fresh blood from the anus, usually in or with the stool (hematochezia)
- Protrusion of an organ or the tissue surrounding it through the wall of the body cavity where it normally lies (hernia)
- Toothache
- Dental caries, cavities in the teeth
- Lower abdominal pain
- Liver injury due to medication toxicity
- Jaw pain
- A disorder characterized by a sudden, irresistible urge to urinate (urinary urgency)
- Irregular menstrual bleeding, vaginal bleeding, dryness of the female vulva and vagina
- Feeling cold in the extremities (hands, feet)
Not known (frequency cannot be estimated from the available data)
- Swollen glands in the neck, under the arm, or in the groin (lymphadenopathy)
- Mood swings
- Irrational thoughts (delusions)
- Psychosis
- Loss of sexual desire
- Feeling hostile
- Severe mistrust (paranoia)
- Aggression
- Attention disorder
- Nightmares
- Confusion, disorientation
- Memory disorder
- Restlessness
- Muscle stiffness, uncontrolled movements, problems with walking or coordination
- Blurred vision, eye pain, eye irritation, eye swelling, watery eyes, increased sensitivity to light (photophobia)
- Ear pain, ear discomfort
- Fluctuating blood pressure
- Breathing difficulties
- Nasal symptoms, stuffy nose, runny nose, sneezing, sinus problems
- Sore throat, voice disorders, cough, yawning
- Hemorrhoids, ulcer
- Diarrhea
- Gas (flatulence)
- Hepatitis
- Acne
- Groin pain
- Muscle pain
- Joint pain
- Unusually frequent urination, pain when urinating
- Chills
- Increased energy
Reporting side effects
If you notice any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this package leaflet. You can also report side effects directly via the national reporting system listed in Annex V. By reporting side effects, you can help provide more information on the safety of this medicine. Date and source of this side effects section: Patient information leaflet (information for patients), Mysimba 8 mg/90 mg prolonged-release tablets (naltrexone hydrochloride/bupropion hydrochloride). Last revised: date not specified (not stated in the document).
Here you will find common questions about Mysimba side effects, warning signs, and how to take it. The answers are based on the patient information leaflet. If symptoms are severe, persistent, or worsening, seek medical advice.
What is Mysimba and what is it used for?
Mysimba contains two active substances, naltrexone hydrochloride and bupropion hydrochloride, and is used for weight management in obese or overweight adults together with a reduced-calorie diet and physical activity. This medicine acts on areas in the brain that control food intake and energy expenditure.
When is treatment with Mysimba discontinued?
Your doctor may stop treatment with Mysimba after 16 weeks if you have not lost at least 5% of your initial body weight. Your doctor may also recommend stopping treatment if there are concerns about increased blood pressure or other concerns regarding the safety or tolerability of this medicine.
Which side effects are very common?
Very common side effects are nausea and vomiting, constipation, and headache.
Which side effects are common?
Common side effects include anxiety, dizziness or vertigo, tremor, sleep disturbances, taste disturbance and dry mouth, difficulty concentrating, fatigue and sleepiness, tinnitus, fast or irregular heartbeat, hot flashes, high blood pressure, upper abdominal pain, abdominal pain, excessive sweating (hyperhidrosis), rash and itching, hair loss, irritability, and feeling scattered.
Which side effects are uncommon, rare, or not known?
Uncommon, rare, and not known side effects are listed in full by frequency in the medical section above.
What warning signs does the package leaflet list for suicidal thoughts or depression?
If you are thinking about harming yourself, have other concerning thoughts, or if you feel depressed and notice that you are getting worse or you develop new symptoms, contact your doctor immediately or go to a hospital right away.
Which signs may indicate seizures?
Symptoms listed include convulsions and usually loss of consciousness. Afterward, you may be confused and may not remember what happened.
Which signs may indicate severe skin reactions?
Erythema multiforme may affect the mouth and other parts of the body and involves red, usually itchy spots starting on the limbs. Stevens-Johnson syndrome is described as severe blistering and bleeding on the lips, eyes, mouth, nose, and genitals.
Which symptoms are listed for rhabdomyolysis?
Symptoms listed include severe muscle cramps, muscle pain, or muscle weakness.
What is important regarding lupus rash or lupus symptoms?
If lupus flare-ups, rashes, or lesions (especially in areas exposed to sunlight) occur while taking Mysimba, contact your doctor immediately, as treatment may need to be stopped.
How is Mysimba dosed?
The starting dose is usually one tablet (8 mg naltrexone hydrochloride / 90 mg bupropion hydrochloride) once daily in the morning. The dose is increased stepwise as follows: Week 1: one tablet once daily, in the morning. Week 2: two tablets daily, one in the morning and one in the evening. Week 3: three tablets daily, two in the morning and one in the evening. Week 4 and thereafter: four tablets daily, two in the morning and two in the evening. The recommended maximum daily dose of Mysimba is two tablets twice daily.
What should I do if I forget a dose?
Skip the missed dose and take the next dose at the usual time. Do not take a double dose to make up for a missed dose.
What should I do in case of overdose?
If you take too many tablets, the risk of having a seizure or other side effects is higher. Do not wait. Contact your doctor immediately or the emergency department of the nearest hospital.
Can I drive or operate machines?
Ask your doctor for advice before driving or operating machines, because Mysimba may cause dizziness and make you sleepy, which can reduce your ability to concentrate and react. Do not drive, use tools, operate machines, or perform hazardous activities until you know how this medicine affects you. If you experience loss of consciousness, muscle weakness, or seizures during treatment, do not drive or operate machines.
Sources
- European Medicines Agency (EMA). Mysimba: EPAR overview page. Page.
- European Medicines Agency (EMA). Mysimba: EPAR product information (SmPC and package leaflet, DE, PDF). Document.
- Federal Institute for Drugs and Medical Devices (BfArM). Safety information: Mysimba, potential long-term cardiovascular risk. Page.
- European Medicines Agency (EMA). EMA concludes review of weight management medicine Mysimba (news). Page.