Risperdal (risperidone) is an atypical antipsychotic medication approved for the treatment of schizophrenia, bipolar disorder, and irritability associated with autistic disorder. It functions by modulating dopamine and serotonin activity in the brain, offering a balanced approach to symptom control with a well-established efficacy and safety profile. This second-generation antipsychotic is widely prescribed due to its ability to address both positive and negative symptoms while minimizing extrapyramidal side effects compared to conventional antipsychotics.

Features

• Contains risperidone as the active pharmaceutical ingredient
• Available in multiple formulations including tablets, orally disintegrating tablets, and long-acting injectable suspension
• Demonstrated efficacy across multiple psychiatric indications in clinical trials
• FDA-approved for use in adults and pediatric patients (specific indications vary by age)
• Manufactured under strict quality control standards ensuring consistent dosing

Benefits

• Reduces frequency and severity of psychotic symptoms including hallucinations and delusions
• Stabilizes mood fluctuations in bipolar disorder patients
• Decreases aggressive behaviors and self-injury in autistic disorder
• Improves overall social functioning and quality of life
• Offers flexible dosing options including once-daily administration for most patients
• Provides long-acting injectable formulation for improved adherence in maintenance therapy

Common use

Risperdal is primarily indicated for the management of schizophrenia in adults and adolescents aged 13-17 years. It is also approved for the acute treatment of manic or mixed episodes associated with bipolar I disorder as monotherapy or adjunctive therapy to lithium or valproate in adults, and as monotherapy in children and adolescents aged 10-17 years. Additionally, it is used for the treatment of irritability associated with autistic disorder in children and adolescents aged 5-16 years, including symptoms of aggression, deliberate self-injury, temper tantrums, and quickly changing moods.

Dosage and direction

Dosage must be individualized based on clinical condition, response, and tolerability. For schizophrenia in adults: initial dose is 2 mg daily, which may be increased to 4 mg daily by day 2. Further adjustments can be made at intervals of not less than 24 hours in increments of 1-2 mg daily. Maximum recommended dose is 8 mg daily. For bipolar mania in adults: initial dose is 2-3 mg once daily. Dose may be adjusted at 24-hour intervals in increments of 1 mg daily. Maximum recommended dose is 6 mg daily. For autistic disorder: initial dose is 0.25 mg daily for patients weighing <20 kg, or 0.5 mg daily for patients weighing ≥20 kg. After at least 4 days, dose may be increased to recommended dose of 0.5 mg daily or 1 mg daily, respectively. Further increases in increments of 0.25 mg daily or 0.5 mg daily may be considered at ≥2-week intervals. Administer once daily or twice daily based on clinical response and tolerability. Tablets may be taken with or without food.

Precautions

Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death. Risperdal is not approved for the treatment of patients with dementia-related psychosis. Cerebrovascular adverse events, including stroke, have been reported in elderly patients with dementia-related psychosis. Neuroleptic malignant syndrome (NMS), a potentially fatal symptom complex, has been reported with antipsychotic drugs. Clinical manifestations include hyperpyrexia, muscle rigidity, altered mental status, and evidence of autonomic instability. Tardive dyskinesia (TD) may develop and may become irreversible. The risk of developing TD and the likelihood that it will become irreversible are believed to increase with the duration of treatment and the cumulative dose. Hyperglycemia and diabetes mellitus have been reported with atypical antipsychotics including Risperdal. Patients should be monitored for symptoms of hyperglycemia. Orthostatic hypotension may occur, particularly during initial dose titration. Use with caution in patients with known cardiovascular disease, cerebrovascular disease, or conditions that would predispose them to hypotension. Seizures have been reported during treatment. Use cautiously in patients with a history of seizures. Esophageal dysmotility and aspiration have been associated with antipsychotic drug use. Use with caution in patients at risk for aspiration pneumonia.

Contraindications

Risperdal is contraindicated in patients with a known hypersensitivity to risperidone or any components of the formulation. Cross-sensitivity may occur with other benzisoxazole derivatives. The use of Risperdal is contraindicated in combination with other drugs that are known to prolong the QT interval, as this may increase the risk of serious cardiac arrhythmias. It should not be used in patients with severe hepatic impairment due to potentially increased exposure to the active metabolite. Concomitant use with strong CYP3A4 inhibitors in patients with renal or hepatic impairment is contraindicated due to the potential for significantly increased risperidone exposure.

Possible side effect

Common adverse reactions (≥5% and at least twice placebo) include: parkinsonism, akathisia, dystonia, tremor, sedation, dizziness, anxiety, blurred vision, nausea, vomiting, upper abdominal pain, stomach discomfort, dyspepsia, diarrhea, saliva increased, constipation, dry mouth, increased appetite, weight gain, fatigue, rash, nasal congestion, upper respiratory tract infection, and pharyngolaryngeal pain. Less common but serious side effects may include: neuroleptic malignant syndrome, tardive dyskinesia, metabolic changes (hyperglycemia, diabetes mellitus, dyslipidemia, weight gain), orthostatic hypotension and syncope, leukopenia/neutropenia/agranulocytosis, hyperprolactinemia, seizures, cognitive and motor impairment, dysphagia, priapism, and temperature regulation dysfunction.

Drug interaction

Risperdal is metabolized by CYP2D6, and its pharmacokinetics may be affected by drugs that inhibit or induce this enzyme. Strong CYP2D6 inhibitors (e.g., paroxetine, fluoxetine) may significantly increase risperidone plasma concentrations. Dose reduction may be necessary when co-administered with strong CYP2D6 inhibitors. Carbamazepine and other enzyme inducers may decrease risperidone plasma concentrations. Dose adjustment may be required when carbamazepine or other enzyme inducers are added to or discontinued from therapy. Due to its alpha-adrenergic blocking activity, risperidone may enhance the hypotensive effects of antihypertensive drugs. Risperidone may antagonize the effects of levodopa and dopamine agonists. Caution is advised when prescribing with other centrally acting drugs due to potential additive sedative effects. Concomitant use with other drugs known to prolong the QT interval should be avoided.

Missed dose

If a dose is missed, it should be taken as soon as remembered. However, if it is almost time for the next dose, the missed dose should be skipped and the regular dosing schedule resumed. Patients should not take a double dose to make up for a missed dose. For patients using the long-acting injectable formulation, if the injection is more than 1 week late for the every-2-weeks regimen or more than 2 weeks late for the every-4-weeks regimen, the patient should be re-initiated on the oral formulation and the injection regimen re-established. Consultation with the prescribing physician is recommended for specific guidance regarding missed doses.

Overdose

In case of overdose, supportive measures should be instituted including maintaining an adequate airway, oxygenation, and ventilation. Cardiovascular monitoring should commence immediately and continue until the QT interval is normalized. Gastric lavage may be indicated if performed soon after ingestion. Administration of activated charcoal may be considered. There is no specific antidote for risperidone overdose. Hypotension and circulatory collapse should be treated with appropriate measures such as intravenous fluids and/or sympathomimetic agents. Epinephrine and dopamine should not be used, as beta stimulation may worsen hypotension in the setting of risperidone-induced alpha blockade. In case of severe extrapyramidal symptoms, anticholinergic medication should be administered. Close medical supervision and monitoring should continue until the patient recovers.

Storage

Store at controlled room temperature 20°C to 25°C (68°F to 77°F); excursions permitted between 15°C to 30°C (59°F to 86°F). Protect from light and moisture. Keep the medication in its original container, tightly closed. Keep out of reach of children and pets. Do not freeze the oral solution. The long-acting injectable formulation should be stored in the refrigerator between 2°C to 8°C (36°F to 46°F). Do not freeze. Protect from light. Keep the vial in the original carton until time of use. The reconstituted suspension may be kept at room temperature but must be used within 6 hours of reconstitution.

Disclaimer

This information is provided for educational purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional before starting or changing any medication regimen. The prescribing information provided here may not include all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of a warning for a given drug or drug combination should not be construed to indicate that the drug or combination is safe, effective, or appropriate for any given patient. Healthcare professionals should consult the full prescribing information and use their professional judgment in treating patients.

Reviews

Clinical studies have demonstrated Risperdal’s efficacy across multiple indications. In schizophrenia trials, risperidone significantly improved Positive and Negative Syndrome Scale (PANSS) scores compared to placebo. Bipolar disorder studies showed significant improvement in Young Mania Rating Scale scores. For irritability associated with autistic disorder, risperidone demonstrated significant improvement on the Aberrant Behavior Checklist irritability subscale. Long-term studies support maintenance of effect with continued treatment. The long-acting injectable formulation has shown significant reduction in relapse rates compared to placebo in maintenance treatment of schizophrenia. Real-world evidence continues to support the favorable benefit-risk profile of risperidone when used appropriately under medical supervision.