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Terms Of Use


Brand Name(s) : Risperdal Consta, Risperdal liquid, Risperdal Quicklet, Risperdal tablets, Risperidone tablets
Side Effects


Risperidone should be used with caution in:

Children and adolescents as they must be fully assessed to find out the causes of their aggressive behaviour

It should not be used in:

  • People who are allergic to risperidone or any of the ingredients in the medicine
  • People with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption, if taking risperidone standard tablets as they contain lactose

Also see list of precautions and interactions


Do not store above 30°C. Keep out of the reach and sight of children.


What is it used for?

  • Risperidone is used to treat schizophrenia and manic episodes in people with bipolar disorder. Risperidone is also used to control persistent aggression.
  • It is an atypical antipsychotic, sometimes known as a neuroleptic. Atypical antipsychotics may be better tolerated than other antipsychotics with fewer side effects of abnormal movements. Risperidone is also an antimanic and mood stabilising agent.
  • It is used to control symptoms of agitation and disturbing behaviour associated with mania and schizophrenia. The symptoms of mania include feeling high, having excessive amounts of energy and sometimes being very irritable. Symptoms of schizophrenia include hallucinations (hearing, seeing or sensing things which are not there), abnormal thoughts (mistaken beliefs, unusual suspiciousness) and becoming withdrawn. It is also used on a short-term basis to control aggression when people may harm themselves or others.
  • In general this drug is used to control mood and behaviour in people with schizophrenia or in people with manic episodes of bipolar disorder.
  • Benefits of being on this drug can include improvements in the symptoms of schizophrenia and mania. It also helps to prevent symptoms come back. Risperidone has a calming effect on aggressive behaviour.

Listed below are the typical uses of risperidone.

  • Schizophrenia
  • Moderate to severe manic episodes associated with bipolar disorders
  • Short-term treatment of persistent aggression in Alzheimer'sdementia
  • Short-term treatment of persistent aggression in conduct disorder in children (aged 5 to 18)

On occasion your doctor may prescribe this medicine to treat a condition not on the above list.


How often do I take it?

  • Risperdal tablets, Risperidone tablets and Risperdal liquid
  • Take this medication by mouth, once or twice daily as directed by your doctor, with or without food. People normally start treatment on a low dose which is adjusted up by your doctor according to each individual.

Risperdal Quicklet (orodispersible tablets)

  • Take this medication by mouth, usually once or twice daily as directed by your doctor, with or without food. Care must be taken to follow the instructions on how to take it in your patient information leaflet.

Risperdal Consta

  • This formulation is an injectable long-acting form of risperidone. It is given by an injection into your muscle (intramuscular injection) every two weeks by a doctor or nurse.

Use this medication for the duration of prescription in order to get the most benefit from it.

Remember to use it at the same time each day - unless specifically told otherwise by your doctor.

It may take up to a few weeks before the full benefit of this drug takes effect.

Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • This medication may cause tiredness, dizziness and blurred vision. You should not drive or operate machinery until you have consulted your doctor or pharmacist for more details.

When can I stop?

  • It is important to continue taking this medication even if you feel well, unless your doctor tells you to stop. You must follow your doctor's instructions for stopping this medication as the dose may need to be lowered gradually over a few days.


  • Headache
  • Difficulty getting to sleep and/or staying asleep
  • Parkinsonism symptoms (e.g. problems with movement, tremor, rigidity)
  • Poor bladder control and bed-wetting
  • Weight gain
  • Sleepiness and drowsiness
  • Abnormal laboratory test results - Increases in blood prolactin levels
  • Changes in appetite
  • Blurred vision
  • Nose bleeds
  • Breathlessness
  • Cough, stuffy nose and sore throat
  • Dizziness
  • Restlessness
  • Unusual body movements (e.g. face, tongue)
  • Nausea and vomiting
  • Stomach ache
  • Diarrhoea
  • Constipation
  • Dry mouth
  • Rash
  • Rapid heart beat
  • Weakness
  • Tiredness
  • Pain in some areas of the body (e.g. back, hands, feet)
  • Chest and urinary tract infections
  • Feeling hot
  • Chest pain
  • Anxiety
  • Agitation
  • Water retention leading to swelling of the hands, ankles or feet (oedema)

Children and adolescents must be closely monitored for:

  • Drowsiness
  • Weight gain
  • Increases in blood prolactin and possible effects on growth and sexual development
  • Unusual body movements

If any of these persist or you consider them severe then inform your doctor.

Tell your doctor immediately if you develop any of the following symptoms:

  • High fever alone or in combination with stiff muscles, change in mental state, rapid breathing and rapid heart rate as these may be signs of a serious, but rare condition known as neuroleptic malignant syndrome. This arises from a reaction to antipsychotic medicines.

Unusual body movements (e.g. face, tongue)

Sudden weakness or numbness in the face, arms or legs, and speech or vision problems as these may be a sign or symptom of a stroke or mini-stroke, particularly in the elderly with Alzheimer's dementia

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking risperidone, tell your doctor or pharmacist if you are allergic to it; or to other atypical antipsychotics; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have:

  • Galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption (as risperidone standard tablets contain lactose)

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following:

  • Alzheimer's dementia
  • Dementia with lewy bodies
  • Dementia in the elderly
  • Parkinson's disease
  • Diabetes
  • Raised prolactin levels or tumours which may be dependent on prolactin
  • Reduced liver or kidney function
  • Cardiovascular disease
  • Stroke or a mini-stroke
  • Abnormal heart rhythm (from an ECG scan) or family history of this
  • Low blood levels of potassium (hypokalaemia) or magnesium (hypomagnesaemia)
  • Fits (seizures, e.g. epilepsy)
  • Pregnancy
  • Breast feeding women
  • Phenylketoneuria

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • Drinking alcohol should be avoided as taken together with risperidone may make you feel drowsy.

The elderly: risperidone should be used with caution in the elderly with dementia as it may lead to serious side effects such as a stroke. Risepridone should not be taken in elderly people with dementia due to a stroke.

Pregnancy and breastfeeding - please ensure you read the detailed information below


Risperidone may be suitable to take during pregnancy, but safety has not been clearly established. Therefore it should not to be used unless clearly necessary and under careful supervision of your doctor. Ask your doctor or pharmacist if you have any doubts or questions about this.
Shaking, muscle stiffness and feeding problems, all of which are reversible, have been seen in newborn babies when risperidone was used during the last trimester of pregnancy.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Risperidone may be suitable to take if you are breastfeeding, although small amounts are excreted in breast milk and the effects on the infant are unknown. It should not be taken without careful discussion with your doctor.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Before using this medicine, tell your prescriber of all the medicines you are taking including prescription medicines and medicines you have bought over the counter without a prescription. Tell your prescriber if you are taking vitamins or complementary remedies such as herbal products, as these can also interact with medicines.

If you are taking more than one medicine, these may interact with each other. Your prescriber may decide to use medicines which interact with each other if the benefit outweighs the risks. In these cases, the dose of your medicines may need to be adjusted or you may be monitored more closely.

The following medicines may interact with risperidone:

  • Paliperidone (a medicine which is similar to risperidone)
  • Levodopa and other dopamine agonists used to treat Parkinson's disease
  • Blood pressure lowering medication
  • Furosemide, a water tablet/diuretic (in the elderly with dementia)
  • Medicines that lead to low potassium levels such as some water tablets (diuretics)
  • Medicines acting on the brain such as opiates for pain, benzodiazepines as calming drugs and antihistamines for allergy
  • Medicines that slow the heart rate
  • Medicines known to change the electrical activity of the heart such as those affecting the heart rhythm (antiarrhythmics) and some types of medicines used in the treatment of:
    - allergies (antihistamines)
    - mental health problems (antidepressants and antipsychotics)
    - malaria (antimalarials)

Medicines that may reduce the effect of risperidone

  • Carbamazepine, phenobarbital and phenytoin used to treat epilepsy
  • Rifampicin (an antibiotic)

Medicines that may increase the effect of risperidone

  • Fluoxetine and paroxetine (antidepressants)
  • Quinidine
  • Medicines acting on the brain e.g. phenothiazines, tricyclic antidepressants
  • Some beta blockers (used to lower blood pressure)

This information does not contain all possible interactions. Therefore, tell your prescriber of all the products you are using before taking this medicine.

If you have a question or want to discuss anything about your medicine, speak to your local pharmacist.


See a doctor right away. Take the medicine pack with you.

In case of overdose you may feel sleepy or tired, or have abnormal body movements, problems standing and walking, feel dizzy due to low blood pressure, or have abnormal heart beats or fits.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of risperidone or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.


If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
If you miss two or more doses, contact your doctor.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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