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Drugs reference index «Risperidone»



Pronunciation: (ris-PER-i-done)Class: Benzisoxazole antipsychotic

Trade Names:Risperdal- Tablets 0.25 mg- Tablets 0.5 mg- Tablets 1 mg- Tablets 2 mg- Tablets 3 mg- Tablets 4 mg- Solution, oral 1 mg/mL

Trade Names:Risperdal Consta- Injection, powder for suspension, ER 12.5 mg- Injection, powder for suspension, ER 25 mg- Injection, powder for suspension, ER 37.5 mg- Injection, powder for suspension, ER 50 mg

Trade Names:Risperdal M-TAB- Tablets, orally disintegrating 0.5 mg- Tablets, orally disintegrating 1 mg- Tablets, orally disintegrating 2 mg- Tablets, orally disintegrating 3 mg- Tablets, orally disintegrating 4 mg

Apo-Risperidone (Canada)CO Risperidone (Canada)Gen-Risperidone (Canada)Novo-Risperidone (Canada)PMS-Risperidone (Canada)ratio-Risperidone (Canada)Sandoz Risperidone (Canada)


Has antipsychotic effect, apparently caused by dopamine- and serotonin-receptor blocking in CNS.



PO Absolute oral bioavailability is 70%. T max is 1 h (risperidone), 3 h (9-hydroxyrisperidone extensive metabolizers), or 17 h (9-hydroxyrisperidone poor metabolizers). Steady state is about 1 day (extensive metabolizers) or about 5 days (poor metabolizers). IM The main release of the drug starts 3 wk after injection, is maintained from 4 to 6 wk, and subsides by 7 wk. Steady state is reached after 4 injections.


Rapidly distributed. Vd is 1 to 2 L/kg. Protein binding is about 90% (parent compound) or about 77% (9-hydroxyrisperidone).


Extensively metabolized in the liver by CYP2D6 to major active metabolite 9-hydroxyrisperidone. 9-hydroxyrisperidone has similar activity to risperidone.


Eliminated in urine (70%) and feces (14%). PO The half-life is 3 and 20 h for risperidone extensive and poor metabolizers, respectively; 21 and 30 h for 9-hydroxyrisperidone extensive and poor metabolizers, respectively; or 20 h (overall mean half-life) for combined risperidone and 9-hydroxyrisperidone. IM The half-life of risperidone plus 9-hydroxyrisperidone is 3 to 6 days. The Cl of risperidone and risperidone plus 9-hydroxyrisperidone is 13.7 and 5 L/h, respectively, for extensive metabolizers and 3.3 and 3.2 L/h, respectively, for poor metabolizers.

Special Populations

Renal Function Impairment

Moderate to severe: Cl of parent drug and active metabolite decreased 60%. Dosage reduction recommended.

Hepatic Function Impairment

Mean free fraction of risperidone in plasma increased about 35%. Dosage reduction recommended.


PO Renal Cl of parent drug and active metabolite was decreased. Elimination half-life was prolonged. Modify dose accordingly. IM No dosing changes required.


No pharmacokinetic differences identified.


No pharmacokinetic differences identified.

Indications and Usage

PO Acute and maintenance treatment of schizophrenia; short-term treatment of acute manic or mixed episodes associated with bipolar I disorder as monotherapy or as adjunct therapy to lithium or valproate; treatment of irritability associated with autistic disorder.

IM Treatment of schizophrenia; as monotherapy or as adjunctive therapy to lithium or valproate for the maintenance treatment of bipolar I disorder.

Unlabeled Uses

Treatment of patients with obsessive-compulsive disorder refractory to SSRIs, stuttering, Tourette syndrome, or chronic tic disorder (oral).


Standard considerations.

Dosage and Administration

Bipolar ManiaAdults

PO 2 to 3 mg/day once daily initially. Adjust dose at intervals of no less than 24 h, in increments/decrements of 1 mg/day (max, 6 mg/day). No data to support acute treatment beyond 3 wk. IM 25 mg every 2 wk (max, 50 mg every 2 wk).

Children 10 to 17 yr of age

PO Administer once daily in the morning or evening. Start with 0.5 mg once daily. If indicated, dosage adjustments should occur at intervals of no less than 24 h and in increments of 0.5 or 1 mg/day, as tolerated, to a recommended dosage of 2.5 mg/day (max, 6 mg/day). Patients experiencing persistent somnolence may benefit from administering half the dose twice daily. There are no data to support treatment beyond 3 wk.

Irritability Associated With Autistic DisorderChildren 5 to 16 yr of age

PO Can be administered once daily or half the total daily dose twice daily. Use caution with dosages for children weighing less than 15 kg. For patients less than 20 kg, the initial dosage is 0.25 mg/day. After a minimum of 4 days, the dosage may be increased to 0.5 mg/day. Maintain this dose for a minimum of 14 days. If sufficient clinical response is not obtained, the dosage may be increased in increments of 0.25 mg/day at intervals of no less than 14 days. Max daily dose is 1 mg. For patients 20 kg or more, the initial dosage is 0.5 mg/day. After a minimum of 4 days, the dosage may be increased to 1 mg/day. Maintain this dose for a minimum of 14 days. If sufficient clinical response is not obtained, the dosage may be increased in increments of 0.5 mg/day at intervals of no less than 14 days. Max daily dose is 2.5 mg for patients 20 to 45 kg and 3 mg for patients weighing more than 45 kg.


PO Can be administered once or twice daily. Initial dosage is 2 mg/day. Dosage increases should occur at intervals of no less than 24 h, in increments of 1 to 2 mg/day as tolerated, to a recommended dosage of 4 to 8 mg/day (max, 16 mg/day). Periodically assess patients to determine need for maintenance treatment with an appropriate dose. IM 25 mg every 2 wk (max, 50 mg every 2 wk). Do not make upward dosage adjustments more frequently than every 4 wk.

Adolescents (13 to 17 yr of age)

PO Initiate treatment with 0.5 mg once daily as a single dose in morning or evening. If indicated, dosage adjustments should be at intervals of no less than 24 h, in increments of 0.5 to 1 mg/day, as tolerated, to a recommended dosage of 3 mg/day (max, 6 mg/day).

Special PopulationsElderly and patients with renal or hepatic function impairment who can tolerate at least 2 mg of oral risperidone

IM 25 mg every 2 wk.

Elderly or debilitated patients, patients with severe renal or hepatic function impairment, and patients predisposed to hypotension or for whom hypotension may pose a risk

PO 0.5 mg twice daily initially; increase in 0.5 mg increments twice daily thereafter. Increases above 1.5 mg twice daily should generally occur at intervals of at least 1 wk.

General Advice

  • When coadministered with enzyme inducers (eg, carbamazepine, phenobarbital, phenytoin, rifampin) or inhibitors (eg, fluoxetine, paroxetine), the risperidone dose needs to be titrated, especially during initiation or discontinuation of therapy.
  • Tablets
  • Administer without regard to food.
  • Orally disintegrating tablet
  • Do not push tablet through foil.
  • Using dry hands, remove tablet from blister by peeling back foil and immediately place on tongue.
  • Tablets disintegrate within seconds and can be swallowed with or without liquid.
  • Instruct patients to not split or chew tablet.
  • Injection
  • For IM administration only. Not for intradermal, subcutaneous, IV, or intra-arterial administration.
  • Administer by deep IM deltoid or gluteal injection. For deltoid administration, use the 1-inch needle, alternating injections between the 2 arms. For gluteal administration, use the 2-inch needle, alternating between the 2 buttocks.
  • For patients who have never taken oral risperidone, it is recommended to establish tolerability with oral risperidone prior to initiating treatment with risperidone injection.
  • Oral risperidone (or another antipsychotic medication) should be given with the first injection of risperidone and should be continued for 3 wk to ensure that adequate therapeutic plasma concentrations are maintained prior to the main release phase of risperidone from the injection site.
  • Do not combine 2 different dosage strengths of risperidone in a single administration.
  • Allow dose pack from refrigerator to reach room temperature before reconstituting powder for injection.
  • Reconstitute powder for injection following manufacturer's guidelines and using the supplied diluent.
  • Administer suspension immediately after reconstitution. If not administered immediately after reconstitution, the suspension must be administered within 6 h. If injection is not administered immediately after reconstitution, resuspend injection following manufacturer's guidelines
  • When switching schizophrenic patients from depot antipsychotics, initiate risperidone therapy in place of the next scheduled injection.
  • Oral solution
  • Administer directly from calibrated pipette or mix with a beverage (ie, water, coffee, orange juice, or low-fat milk) prior to administration. Do not mix with cola or tea.


Store tablets, orally disintegrating tablets, and oral solution at 59° to 77°F. Protect tablets from light and moisture. Protect oral solution from light and freezing. Store injection dose pack in refrigerator (36° to 46°F). Protect from light. If refrigeration is unavailable, store at temperatures not exceeding 77°F for no more than 7 days prior to reconstitution. Once in suspension, avoid exposure to temperatures exceeding 77°F. Discard suspension if not administered within 6 h of reconstitution.

Drug Interactions

Alcohol, CNS depressants

May cause additive CNS depressant effects.


Risperidone may enhance hypotensive effects of some antihypertensives.

Cimetidine, ranitidine

May increase bioavailability of risperidone.

Enzyme inducers (eg, carbamazepine, phenobarbital, phenytoin, rifampin)

Risperidone plasma levels may be reduced, decreasing the efficacy.

Inhibitors of CYP2D6 (eg, clozapine, SSRIs [eg, fluoxetine, paroxetine, sertraline], thioridazine) and other CYP isozymes (eg, indinavir, itraconazole, ketoconazole, ritonavir)

Risperidone plasma levels may be elevated, increasing the therapeutic effects and adverse reactions.

Lamotrigine, verapamil

Risperidone plasma concentrations may be increased.

Levodopa and other dopamine agonists

Risperidone may antagonize the effects of levodopa and other dopamine agonists.

Maprotiline, valproate

Peak plasma levels may be increased by risperidone.

QT prolongating drugs

An additive effect of risperidone with other drugs that prolong the QT interval cannot be excluded. The following drugs may prolong the QT interval and increase the risk of life-threatening cardiac arrhythmias, including torsades de pointes: antiarrhythmic agents (eg, amiodarone, bretylium, disopyramide, dofetilide, procainamide, quinidine, sotalol), arsenic trioxide, chlorpromazine, cisapride, dolasetron, droperidol, mefloquine, mesoridazine, moxifloxacin, pentamidine, pimozide, tacrolimus, thioridazine, ziprasidone.

Laboratory Test Interactions

None well documented.

Adverse Reactions


Tachycardia (7%); AV block, bundle branch block, cerebrovascular disorder (less than 5%); bradycardia (less than 4%); hypertension (3%); palpitation, postural hypotension, syncope (2%); arrhythmia, hypotension (1%); atrial fibrillation, cardiopulmonary arrest, cerebrovascular disorder, QT prolongation (postmarketing).


Somnolence (67%); fatigue (42%); extrapyramidal symptoms (31%); tremor (24%); headache (21%); parkinsonism (20%); dystonia (18%); anxiety, dizziness (16%); akathisia (11%); automatism, dyskinesia, sedation (7%); confusion (5%); abnormal gait, agitation, apathy, ataxia, coma, decreased libido, dysphonia, emotional lability, hypoesthesia, impaired concentration, impotence, insomnia, malaise, nervousness, NMS, speech disorder, stupor, tardive dyskinesia, vertigo (less than 5%); asthenia (1%); mania (postmarketing).


Rash (11%); erythema multiforme, erythematous rash, maculopapular rash, skin discoloration, skin exfoliation, skin ulceration (less than 5%); acne, dry skin, seborrhea (2%); alopecia (postmarketing).


Hyperprolactinemia (less than 5%).


Rhinitis (36%); abnormal vision (7%); pharyngitis (5%); conjunctivitis, otitis media (less than 5%); blurred vision (3%); earache (1%); retinal artery occlusion (postmarketing).


Increased appetite (49%); vomiting (25%); increased salivation (22%); constipation (21%); abdominal pain (18%); dyspepsia, nausea (16%); dry mouth (13%); anorexia, diarrhea (8%); decreased appetite (6%); dysphagia, flatulence (less than 5%); toothache (3%); intestinal obstruction, pancreatitis (postmarketing).


Urinary incontinence (22%); lactation nonpuerperal (5%); abnormal sexual function, amenorrhea, ejaculation disorder, gynecomastia, leukorrhea, menstrual disorder, micturition frequency, priapism (less than 5%); UTI (3%); ejaculation failure (1%); precocious puberty (postmarketing).


Granulocytopenia, leukopenia, purpura (less than 5%); epistaxis (2%); anemia (1%); agranulocytosis, thrombocytopenia (postmarketing).


Increased ALT, increased hepatic enzymes (less than 5%); jaundice (postmarketing).


Injection-site pain (at least 1%); injection-site reactions including abscess, cellulitis, cyst, hematoma necrosis, nodule, or ulcer (postmarketing).


Weight increase (5%); aggravated diabetes mellitus, diabetic coma, generalized edema, hyperglycemia, peripheral edema, thirst, xerophthalmia (less than 5%); weight decrease (4%); increased CPK (2%); diabetic ketoacidosis, SIADH, water intoxication (postmarketing).


Pain in extremity (6%); leg cramps, muscle weakness, rhabdomyolysis (less than 5%); arthralgia (4%); myalgia (less than 4%); back pain (3%).


Upper respiratory tract infection (34%); coughing (24%); dyspnea (5%); respiratory disorder (less than 5%); sinusitis (less than 4%); apnea, pulmonary embolism (postmarketing).


Fever (20%); abnormal crying, allergic reaction, allergy, allergy aggravated, anaphylactoid reaction, hypothermia, influenza-like symptoms, leg pain, pain, rigors, speech disorder, viral infection (less than 5%); chest pain (3%); angioedema, pituitary adenomas, sudden death (postmarketing).



Increased mortality

Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death. Over the course of a 10-wk controlled trial, the rate of death in drug-treated patients was about 4.5% compared with 2.6% in the placebo group. Although the causes of death were varied, most of the deaths appeared to be either CV (eg, heart failure, sudden death) or infectious (eg, pneumonia) in nature. Risperidone is not approved for the treatment of patients with dementia-related psychosis.


Regularly monitor patients with established diagnosis of diabetes mellitus for worsening of glucose control. Perform fasting blood glucose testing at the beginning of treatment and periodically during treatment of patients with risk factors for diabetes mellitus (eg, family history of diabetes, obesity). Monitor any patient treated with atypical antipsychotics for symptoms of hyperglycemia, including polydipsia, polyuria, polyphagia, and weakness. Perform fasting blood glucose testing on patients who develop symptoms of hyperglycemia during treatment with atypical antipsychotics. In some cases, hyperglycemia has resolved when the atypical antipsychotic was discontinued; however, some patients required continuation of antidiabetic treatment despite discontinuation of the suspect drug. Consider monitoring of orthostatic vital signs in patients predisposed to hypotension (eg, CV disease, cerebrovascular disease, dehydration, hypovolemia, elderly, renal/hepatic impairment). Monitor renal function in patients with renal impairment. If a patient requires risperidone treatment after recovery from NMS, carefully monitor the patient because recurrences of NMS have been reported.


Category C .


Excreted in breast milk.


Safety and efficacy of IM dose in children not established.

Autistic disorder

Safety and efficacy not established in children younger than 5 yr of age.

Bipolar disorder

Safety and efficacy not established in children younger than 10 yr of age.


Safety and efficacy not established in children younger than 13 yr of age.


Elderly and debilitated patients may have reduced ability to eliminate risperidone. Increased risk of tardive dyskinesia, especially in elderly women. Cerebrovascular adverse reactions and fatalities may occur. Dosage adjustment may be required.

Renal Function

May experience enhanced effects of risperidone because of reduced ability to eliminate risperidone. Dose adjustment may be required.

Hepatic Function

May experience enhanced effects of risperidone because of decreased protein binding. Dose adjustment may be required.

Special Risk Patients

Use with caution in patients with Parkinson disease, dementia with Lewy bodies, or conditions that could affect metabolism or hemodynamic responses.

Antiemetic effect

This effect may mask signs and symptoms of overdosage with certain drugs or conditions, such as intestinal obstruction.

Aspiration pneumonia

Antipsychotics have been associated with esophageal dysmotility and aspiration. Use with caution in patients at risk for aspiration pneumonia.

Body temperature regulation

Antipsychotics can disrupt the body's ability to reduce core temperature.

Cardiac effects

Appears to have proarrhythmic effects.

Cerebrovascular adverse reactions

Cerebrovascular adverse reactions (eg, stroke, transient ischemic attack), including fatalities, may occur, especially in elderly patients.

Cognitive and motor performance

Judgment, thinking, or motor skills may be impaired.

Hyperglycemia and diabetes mellitus

Hyperglycemia, in some cases extreme and associated with ketoacidosis, hyperosmolar coma, or death, may occur.


May elevate prolactin levels.

Long-term use (more than 8 wk)

Long-term use not well evaluated. Periodically reevaluate usefulness.


Has occurred with antipsychotics and is potentially fatal. Signs and symptoms are altered mental status, cardiac dysrhythmia, diaphoresis, hyperpyrexia, irregular BP, irregular pulse, muscle rigidity, and tachycardia.

Orthostatic hypotension

Orthostatic hypotension, associated with dizziness, syncope, and tachycardia, may occur.


The orally disintegrating tablet contains phenylalanine.


Other drugs with alpha-adrenergic properties have been reported to cause priapism. Reports with risperidone are rare and a causal relationship has not been established. No cases have been reported with IM risperidone.


Seizures may occur. Use with caution in patients with a history of seizures.


Possible suicide attempts are inherent in schizophrenia and bipolar disorder. Closely supervise high-risk patients. Prescribe the smallest quantity consistent with good patient management.

Tardive dyskinesia

A potentially irreversible syndrome of involuntary body and facial movements may occur.

Thrombotic thrombocytopenia purpura

Has occurred in 1 patient; relationship to risperidone is unknown.



Cardiopulmonary arrest, convulsions, drowsiness, extrapyramidal symptoms, hypokalemia, hyponatremia, hypotension, prolonged QT and widened QRS intervals, sedation, tachycardia, torsades de pointes.

Patient Information

  • Instruct patient to take prescribed dose once or twice daily as prescribed, without regard to meals. Advise patient to take with food if GI upset occurs.
  • Advise patient receiving risperidone injection that medication will be prepared and administered by health care provider in a medical setting.
  • Instruct patient using oral solution to use calibrated pipette to measure each dose. Advise patient that solution may be mixed with 3 to 4 oz of water, coffee, orange juice, or low-fat milk (but not with cola or tea) prior to administration.
  • Caution patient using orally disintegrating tablet not to open the blister until ready to take the dose.
  • Advise patient that dose will be started low and then increased until max benefit is obtained.
  • Instruct patient not to stop taking risperidone when feeling better.
  • Tell patient to immediately report altered mental status, high fever, irregular pulse, muscle rigidity, rash, seizures, or sweating to health care provider.
  • Instruct patient to contact health care provider if symptoms do not appear to improve or if they worsen.
  • Advise patient to notify health care provider of the following: changes in personality or mood, excessive drowsiness, excessive thirst, frequent urination, involuntary body or facial movements, weight gain.
  • Advise patient to avoid strenuous activity during periods of high temperature or humidity.
  • Instruct diabetic patient to monitor blood glucose more frequently when drug is started or dose is changed, and to inform health care provider of significant changes in readings.
  • Instruct patient to avoid alcoholic beverages and sedatives (eg, diazepam) while taking risperidone.
  • Instruct patient to get up slowly from lying or sitting position and to avoid sudden position changes to prevent postural hypotension. Advise patient to report dizziness with position changes to health care provider. Caution patient that hot tubs and hot showers or baths may make dizziness worse.
  • Advise patient taking antihypertensives to monitor BP at regular intervals.
  • Advise patient that drug may impair judgment, thinking, or motor skills, or cause drowsiness, and to use caution while driving or performing other tasks requiring mental alertness until tolerance is determined.
  • Advise breast-feeding mother not to breast-feed during therapy and for at least 12 wk after last injection of risperidone.
  • Advise phenylketonuric patients that orally disintegrating tablet contains phenylalanine.
  • Advise patient that medication may cause photosensitivity and to use sunscreen or wear protective clothing until tolerance to the sun/UV light is determined.

Copyright © 2009 Wolters Kluwer Health.

  • Risperidone MedFacts Consumer Leaflet (Wolters Kluwer)
  • Risperidone Prescribing Information (FDA)
  • Risperidone Detailed Consumer Information (PDR)
  • risperidone Advanced Consumer (Micromedex) - Includes Dosage Information
  • Risperdal Consumer Overview
  • Risperdal Prescribing Information (FDA)
  • Risperdal MedFacts Consumer Leaflet (Wolters Kluwer)
  • Risperdal Consta Prescribing Information (FDA)
  • Risperdal Consta Advanced Consumer (Micromedex) - Includes Dosage Information
  • Risperdal Consta Consumer Overview
  • Risperdal M-Tab Orally Disintegrating Tablets MedFacts Consumer Leaflet (Wolters Kluwer)

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