What is Risperidone and what is it used for?
Risperidone is used to treat certain mental/mood disorders (such as schizophrenia, bipolar disorder, irritability associated with autistic disorder). This medication can help you to think clearly and take part in everyday life. Risperidone belongs to a class of drugs called atypical antipsychotics.
How does Risperidone work?
Risperidone works by blocking the receptors in the brain that dopamine acts on. This prevents the excessive activity of dopamine and helps to control schizophrenia.
Who can and cannot take risperidone?
Risperidone is suitable for adults. It is not usually prescribed for children.
Risperidone is not prescribed for people with dementia that not caused by Alzheimer’s disease, for example mixed or vascular dementia.
Some people, particularly the elderly may need a lower dose of risperidone or extra monitoring. This includes the following:
- Elderly people with Alzheimer’s dementia who are also being treated with furosemide or other strong diuretics. It is important that dehydration is avoided in these people.
- People with liver or kidney disease.
- People who are dehydrated.
- People with low blood pressure or high blood pressure.
- People with disease involving the heart and blood vessels (cardiovascular disease) for example heart failure, angina, previous heart attack or an irregular heartbeat (arrhythmia).
- People with a very slow heart rate (bradycardia).
- People with a personal or family history of an abnormal heart rhythm seen as a ‘prolonged QT interval’ on a heart monitoring trace or ECG.
- People taking other medicines that can increase the risk of a ‘prolonged QT interval’
- People with disturbances in the levels of salts (electrolytes) in their blood, especially low blood potassium or magnesium levels.
- People with a history or risk of stroke or small temporary strokes (transient ischaemic attacks).
- People with a personal or family history of blood clots (venous thromboembolism), for example in a vein of the leg (deep vein thrombosis) or in the lungs (pulmonary embolism).
- People with other risk factors for getting a blood clot, for example smoking, being overweight, taking the contraceptive pill, being over 40, recent major surgery or being immobile for prolonged periods.
- Diabetes. (If you have diabetes your blood sugar levels should be monitored closely while you are having treatment with this medicine, because it may increase your blood sugar.)
- People with a history of seizures, eg epilepsy.
- People with conditions that increase the risk of epilepsy or convulsions, eg brain damage or withdrawal from alcohol.
- Parkinson’s disease.
- People with high levels of the hormone prolactin in the blood (hyperprolactinaemia).
- People with a tumour that is possibly dependent on prolactin, such as breast cancer
What are the side effects of risperidone?
Medicines and their possible side effects can affect people in different ways. The following are some of the side effects that may be associated with risperidone. Just because a side effect is stated here doesn’t mean that all people taking risperidone will experience that or any side effect.
- Sleepiness, fatigue or sedation.
- Restlessness, agitation or anxiety.
- Change in appetite.
- Weight gain – see warning section above.
- Increased level of the hormone prolactin in the blood (hyperprolactinaemia) – uncommonly this may lead to symptoms such as breast enlargement, production of breast milk and menstrual disturbances.
- Blurred vision.
- Inflammation of the lining of the nose (rhinitis) causing a blocked or runny nose.
- Cough or shortness of breath.
- Dry mouth.
- Disturbances of the gut such as constipation, diarrhoea, nausea, vomiting, indigestion or abdominal pain.
- Swollen ankles.
- Fast heartbeat.
- Chest pain.