Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.
Quick facts
- Drug class
- Atypical Antipsychotic [EPC]
- How it is given
- oral
- Type
- human prescription drug
- RxNorm ID
- 312830
We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.
What it is used to treat
Risperidone tablets are an atypical antipsychotic indicated for: Treatment of schizophrenia ( 1.1 ) As monotherapy or adjunctive therapy with lithium or valproate, for the treatment of acute manic or mixed episodes associated with Bipolar I Disorder ( 1.2 ) Treatment of irritability associated with autistic disorder ( 1.3 ) 1.1 Schizophrenia Risperidone tablets are indicated for the treatment of schizophrenia. Efficacy was established in 4 short-term trials in adults, 2 short-term trials in adolescents (ages 13 to 17 years), and one long-term maintenance trial in adults [see Clinical Studies (14.1) ] . 1.2 Bipolar Mania Monotherapy Risperidone tablets are indicated for the treatment of acute manic or mixed episodes associated with Bipolar I Disorder. Efficacy was established in 2 short-term trials in adults and one short-term trial in children and adolescents (ages 10 to 17 years) [see Clinical Studies (14.2) ] . Adjunctive Therapy Risperidone tablets adjunctive therapy with lithium or valproate is indicated for the treatment of acute manic or mixed episodes associated with Bipolar I Disorder. Efficacy was established in one short-term trial in adults [see Clinical Studies (14.3) ] . 1.3 Irritability Associated with Autistic Disorder Risperidone tablets are indicated for the treatment of irritability associated with autistic disorder, including symptoms of aggression towards others, deliberate self-injuriousness, temper tantrums, and quickly changing moods. Efficacy was established in 3 short-term trials in children and adolescents (ages 5 to 17 years) [see Clinical Studies (14.4) ] .
About this medicine
Risperidone tablets, USP contain risperidone USP, an atypical antipsychotic belonging to the chemical class of benzisoxazole derivatives. The chemical designation is 3-[2-[4-(6-fluoro-1,2- benzisoxazol-3-yl)-1-piperidinyl]ethyl]-6,7,8,9-tetrahydro-2-methyl-4H-pyrido[1,2-a]pyrimidin-4-one. Its molecular formula is C 23 H 27 FN 4 O 2 and its molecular weight is 410.49. The structural formula is: Risperidone USP is a white to slightly beige powder. It is practically insoluble in water, freely soluble in methylene chloride, and soluble in methanol and 0.1 N HCl. Risperidone tablets, USP are for oral administration and available in 0.25 mg (orange), 0.5 mg (orange), 1 mg (white), 2 mg (yellow), 3 mg (orange), and 4 mg (brown) strengths. Risperidone tablets contain the following inactive ingredients: colloidal silicon dioxide, hypromellose, lactose monohydrate, magnesium stearate, microcrystalline cellulose, propylene glycol (except 1 mg), sodium lauryl sulphate, sodium starch glycolate and polyethylene glycol (1 mg). Tablets of 0.25 mg, 0.5 mg, 2 mg, 3 mg, and 4 mg also contain talc and titanium dioxide. 0.25 mg, 0.5 mg, and 3 mg tablets contain FD&C Yellow # 6 aluminum lake, the 2 mg tablets contain yellow iron oxide; the 4 mg tablets contain iron oxide red. structure
How it works
12.1 Mechanism of Action The mechanism of action of risperidone in schizophrenia is unclear. The drug's therapeutic activity in schizophrenia could be mediated through a combination of dopamine Type 2 (D 2 ) and serotonin Type 2 (5HT 2 ) receptor antagonism. The clinical effect from risperidone results from the combined concentrations of risperidone and its major metabolite, 9-hydroxyrisperidone (paliperidone) [see Clinical Pharmacology ( 12.3 )] . Antagonism at receptors other than D 2 and 5HT 2 may explain some of the other effects of risperidone [see Clinical Pharmacology ( 12.1 )] .
Who should not take it
Risperidone tablets are contraindicated in patients with a known hypersensitivity to either risperidone or paliperidone, or to any of the excipients in the risperidone tablets formulation. Hypersensitivity reactions, including anaphylactic reactions and angioedema, have been reported in patients treated with risperidone and in patients treated with paliperidone. Paliperidone is a metabolite of risperidone. Known hypersensitivity to risperidone, paliperidone, or to any excipients in risperidone tablets. ( 4 )
Warnings and cautions
Cerebrovascular events, including stroke, in elderly patients with dementia-related psychosis: Risperidone tablets are not approved for use in patients with dementia-related psychosis ( 5.2 ) Neuroleptic Malignant Syndrome: Manage with immediate discontinuation of risperidone tablets and close monitoring. ( 5.3 ) Tardive dyskinesia: Consider discontinuing risperidone tablets if clinically indicated. ( 5.4 ) Metabolic Changes: Atypical antipsychotic drugs have been associated with metabolic changes that may increase cardiovascular / cerebrovascular risk. These metabolic changes include hyperglycemia, dyslipidemia, and weight gain. ( 5.5 ) Hyperglycemia and Diabetes Mellitus: Monitor patients for symptoms of hyperglycemia including polydipsia, polyuria, polyphagia and weakness. Monitor glucose regularly in patients with diabetes or at risk for diabetes. ( 5.5 ) Dyslipidemia: Undesirable alterations have been observed in patients treated with atypical antipsychotics. ( 5.5 ) Weight Gain : Significant weight gain has been reported. Monitor weight gain. ( 5.5 ) Hyperprolactinemia: Prolactin elevations occur and persist during chronic administration. ( 5.6 ) Orthostatic hypotension: For patients at risk, consider a lower starting dose and slower titration. ( 5.7 ) Leukopenia, Neutropenia, and Agranulocytosis: Perform complete blood counts in patients with a history of clinically significant low white blood cell count (WBC). Consider discontinuing risperidone tablets if a clinically significant decline in WBC occurs in the absence of other causative factors. ( 5.9 ) Potential for cognitive and motor impairment: Use caution when operating machinery. ( 5.10 ) Seizures: Use cautiously in patients with a history of seizures or with conditions that lower the seizure threshold. ( 5.11 ) 5.1 Increased Mortality in Elderly Patients with Dementia-Related Psychosis Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death. […]
Reported side effects
The following are discussed in more detail in other sections of the labeling: • Increased mortality in elderly patients with dementia-related psychosis [see Boxed Warning and Warnings and Precautions ( 5.1 )] • Cerebrovascular adverse events, including stroke, in elderly patients with dementia-related psychosis [see Warnings and Precautions ( 5.2 )] • Neuroleptic malignant syndrome [see Warnings and Precautions ( 5.3 )] • Tardive dyskinesia [see Warnings and Precautions ( 5.4 )] • Metabolic Changes (Hyperglycemia and diabetes mellitus, Dyslipidemia, and Weight Gain) [see Warnings and Precautions ( 5.5 )] • Hyperprolactinemia [see Warnings and Precautions ( 5.6 )] • Orthostatic hypotension [see Warnings and Precautions ( 5.7 )] • Falls [see Warnings and Precautions ( 5.8 )] • Leukopenia, neutropenia, and agranulocytosis [see Warnings and Precautions ( 5.9 )] • Potential for cognitive and motor impairment [see Warnings and Precautions ( 5.10 )] • Seizures [see Warnings and Precautions ( 5.11 )] • Dysphagia [see Warnings and Precautions ( 5.12 )] • Priapism [see Warnings and Precautions ( 5.13 )] • Disruption of body temperature regulation [see Warnings and Precautions ( 5.14 )] The most common adverse reactions in clinical trials (> 5% and twice placebo) were parkinsonism, akathisia, dystonia, tremor, sedation, dizziness, anxiety, blurred vision, nausea, vomiting, upper abdominal pain, stomach discomfort, dyspepsia, diarrhea, salivary hypersecretion, constipation, dry mouth, increased appetite, increased weight, fatigue, rash, nasal congestion, upper respiratory tract infection, nasopharyngitis, and pharyngolaryngeal pain. The most common adverse reactions that were associated with discontinuation from clinical trials (causing discontinuation in >1% of adults and/or >2% of pediatrics) were nausea, somnolence, sedation, vomiting, dizziness, and akathisia [see Adverse Reactions, Discontinuations Due to Adverse Reactions ( 6.1 )] . […]
Interactions with other medicines
Carbamazepine and other enzyme inducers decrease plasma concentrations of risperidone. Increase the risperidone tablets dose up to double the patient’s usual dose. Titrate slowly. ( 7.1 ) Fluoxetine, paroxetine, and other CYP 2D6 enzyme inhibitors increase plasma concentrations of risperidone. Reduce the initial dose. Do not exceed a final dose of 8 mg per day of risperidone tablets. ( 7.1 ) 7.1 Pharmacokinetic-related Interactions The dose of risperidone tablets should be adjusted when used in combination with CYP2D6 enzyme inhibitors (e.g., fluoxetine, and paroxetine) and enzyme inducers (e.g., carbamazepine) [see Table 18 and Dosage and Administration (2.5) ]. Dose adjustment is not recommended for risperidone tablets when co-administered with ranitidine, cimetidine, amitriptyline, or erythromycin [see Table 18 ] . Table 18. Summary of Effect of Coadministered Drugs on Exposure to Active Moiety (Risperidone + 9-Hydroxy-Risperidone) in Healthy Subjects or Patients with Schizophrenia Coadministered Drug Dosing Schedule Effect on Active Moiety (Risperidone + 9- Hydroxy- Risperidone (Ratio*) Risperidone Dose Recommendation Coadministered Drug Risperidone AUC C max Enzyme (CYP2D6) inhibitors Fluoxetine 20 mg/day 2 or 3 mg twice daily 1.4 1.5 Re-evaluate dosing. Do not exceed 8 mg/day Paroxetine 10 mg/day 4 mg/day 1.3 - Re-evaluate dosing. Do not exceed 8 mg/day 20 mg/day 4 mg/day 1.6 - 40 mg/day 4 mg/day 1.8 - Enzyme (CYP3A/ PgP inducers) Inducers Carbamazepine 573 ± 168 mg/day 3 mg twice daily 0.51 0.55 Titrate dose upwards. Do not exceed twice the patient’s usual dose Enzyme (CYP3A) inhibitors Ranitidine 150 mg twice daily 1 mg single dose 1.2 1.4 Dose adjustment not needed Cimetidine 400 mg twice daily 1 mg single dose 1.1 1.3 Dose adjustment not needed Erythromycin 500 mg four times daily 1 mg single dose 1.1 0.94 Dose adjustment not needed Other Drugs Amitriptyline 50 mg twice daily 3 mg twice daily 1.2 1.1 Dose adjustment not Needed *Change relative to reference Effect of Risperidone on other drugs Lithium Repeated oral doses of risperidone tablets (3 mg twice daily) did not affect the exposure (AUC) or peak plasma concentrations (C max) of lithium (n=13). […]
Use in specific groups
Pregnancy: May cause extrapyramidal and/or withdrawal symptoms in neonates with third trimester exposure. ( 8.1 ) 8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to atypical antipsychotics, including risperidone, during pregnancy. Healthcare providers are encouraged to register patients by contacting the National Pregnancy Registry for Atypical Antipsychotics at 1-866-961-2388 or online at http://womensmentalhealth.org/clinical-and-research-programs/pregnancyregistry/ . Risk Summary Neonates exposed to antipsychotic drugs during the third trimester of pregnancy are at risk for extrapyramidal and/or withdrawal symptoms following delivery (see Clinical Considerations) . Overall, available data from published epidemiologic studies of pregnant women exposed to risperidone have not established a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes (see Data). There are risks to the mother associated with untreated schizophrenia or bipolar I disorder and with exposure to antipsychotics, including risperidone, during pregnancy (see Clinical Considerations) . Oral administration of risperidone to pregnant mice caused cleft palate at doses 3 to 4 times the maximum recommended human dose (MRHD) with maternal toxicity observed at 4-times MRHD based on mg/m 2 body surface area. Risperidone was not teratogenic in rats or rabbits at doses up to 6-times the MRHD based on mg/m 2 body surface area. Increased stillbirths and decreased birth weight occurred after oral risperidone administration to pregnant rats at 1.5-times the MRHD based on mg/m 2 body surface area. Learning was impaired in offspring of rats when the dams were dosed at 0.6-times the MRHD and offspring mortality increased at doses 0.1 to 3 times the MRHD based on mg/m 2 body surface area. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. […]
If too much is taken
10.1 Human Experience Premarketing experience included eight reports of acute risperidone tablets overdosage with estimated doses ranging from 20 to 300 mg and no fatalities. In general, reported signs and symptoms were those resulting from an exaggeration of the drug's known pharmacological effects, i.e., drowsiness and sedation, tachycardia and hypotension, and extrapyramidal symptoms. One case, involving an estimated overdose of 240 mg, was associated with hyponatremia, hypokalemia, prolonged QT, and widened QRS. Another case, involving an estimated overdose of 36 mg, was associated with a seizure. Postmarketing experience includes reports of acute risperidone tablets overdosage, with estimated doses of up to 360 mg. In general, the most frequently reported signs and symptoms are those resulting from an exaggeration of the drug's known pharmacological effects, i.e., drowsiness, sedation, tachycardia, hypotension, and extrapyramidal symptoms. Other adverse reactions reported since market introduction related to risperidone tablets overdose include prolonged QT interval and convulsions. Torsade de pointes has been reported in association with combined overdose of risperidone tablets and paroxetine. 10.2 Management of Overdosage For the most up to date information on the management of risperidone tablets overdosage, contact a certified poison control center (1-800-222-1222 or www.poison.org). Provide supportive care including close medical supervision and monitoring. Treatment should consist of general measures employed in the management of overdosage with any drug. Consider the possibility of multiple drug overdosage. Ensure an adequate airway, oxygenation, and ventilation. Monitor cardiac rhythm and vital signs. Use supportive and symptomatic measures. There is no specific antidote to risperidone tablets.
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This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 25 June 2026. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.