risperidone at a glance
Medicine class
Second-generation antipsychotic
Main roles
Schizophrenia, manic episodes and narrowly defined persistent aggression
Available forms
Swallowed tablets, orodispersible tablets, oral solution and long-acting injection
Food
Oral risperidone may be taken with or without food
What is risperidone used for?
Selected products are licensed for:
Schizophrenia; the selected prolonged-release injection is for adults whose response and tolerability have been established with oral risperidone.
Moderate to severe manic episodes associated with bipolar disorder, using selected oral products.
Short-term treatment of persistent aggression in moderate to severe Alzheimer’s dementia when non-medicine approaches have not worked and there is a risk of harm.
Short-term symptomatic treatment of persistent aggression in children and adolescents with conduct disorder and subaverage intellectual functioning, as part of a wider psychosocial and educational programme under specialist care.
How does risperidone work?
Risperidone blocks dopamine D2 and serotonin 5-HT2 receptors. Effects at alpha-adrenergic, histamine and dopamine receptors also help explain postural dizziness, sleepiness, movement disorders and raised prolactin.
risperidone preparations and strengths
Dispersible tablet
Route: Oral
Strengths: 0.5 mg, 1 mg, 2 mg, 3 mg, 4 mg
How to take risperidone
Follow the product instructions and prescriber’s directions. Do not stop risperidone suddenly without clinical advice.
Swallow standard tablets with water; they may be taken with or without food.
Handle orodispersible tablets with dry hands, place on the tongue to dissolve; water is optional afterwards.
Measure oral solution with the supplied oral syringe, pipette or cup, not a kitchen spoon.
The prolonged-release injection must be prepared and given into a muscle by a healthcare professional.
risperidone side effects
Common or expected effects
- Sleepiness, tiredness, dizziness or difficulty sleeping
- Headache
- Movement problems such as stiffness, tremor or restlessness
- Increased appetite or weight gain
- Nausea, vomiting, constipation or abdominal discomfort
- Raised prolactin, which may cause breast changes, milk production, menstrual changes or sexual difficulties
Get urgent medical advice
- Fever, severe muscle stiffness, confusion or reduced consciousness
- New involuntary movements, especially of the face or tongue
- Sudden facial or limb weakness, speech difficulty or visual disturbance
- Breathing difficulty or swelling of the face, lips, tongue or throat
- Painful leg swelling, chest pain or sudden breathlessness
- A prolonged painful erection
- Marked thirst, frequent urination or weakness
risperidone in pregnancy
Risperidone may be continued during pregnancy when benefits outweigh potential risks; stopping without advice can cause relapse. UK pregnancy information does not show a clear increase in birth defects, but gestational diabetes, increased fetal growth and newborn adaptation or withdrawal symptoms may require specialist planning and monitoring, particularly near delivery.
risperidone while breastfeeding
Oral risperidone can be used cautiously while breastfeeding a healthy, full-term infant when clinically indicated. Monitor the baby for unusual sleepiness, irritability, poor feeding or weight gain, digestive symptoms, rash or abnormal movements.
risperidone interactions
Check all prescribed, over-the-counter and herbal products with a pharmacist or prescriber. Important examples include:
Benzodiazepines, opioids, sedating antihistamines and alcohol
Sedation, dizziness and impaired alertness may increase.
Carbamazepine, phenytoin and rifampicin
They may lower risperidone exposure and reduce its effect.
Common questions about risperidone
Answers are fully visible for fast scanning and source review.
How long does risperidone take to work?
Some changes may appear within several days, but fuller improvement can take weeks or longer and varies by symptom and person.
Can risperidone be stopped suddenly?
Do not stop without clinical advice. Sudden stopping can allow symptoms to return and may cause nausea, sweating or sleep disturbance.
Can risperidone cause weight gain?
Yes. It can increase appetite and weight, so weight and metabolic risk should be reviewed during treatment.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.