risperidone, Risperdal; Risperdal Consta

Pharmacy Author:
Medical and Pharmacy Editor:

GENERIC NAME: risperidone

BRAND NAME: Risperdal, Risperdal Consta

DRUG CLASS AND MECHANISM: Risperidone is an atypical antipsychotic drug that is used for treating schizophrenia, bipolar mania, and autism. Other atypical antipsychotic drugs include olanzapine (Zyprexa), quetiapine (Seroquel), ziprasidone (Geodon), aripiprazole (Abilify) and paliperidone (Invega). Atypical antipsychotics differ from typical antipsychotics because they cause a lesser degree of movement (extrapyramidal) side effects and constipation. Risperdal Consta is an injectable, long-acting form of risperidone.

The exact mechanism of action of risperidone is not known, but, like other anti-psychotics, it is believed that risperidone affects the way the brain works by interfering with communication among the brain's nerves. Nerves communicate with each other by making and releasing chemicals called neurotransmitters. The neurotransmitters travel to other nearby nerves where they attach to receptors on the nerves. The attachment of the neurotransmitters either stimulates or inhibits the function of the nearby nerves. Risperidone blocks several of the receptors on nerves including dopamine type 2, serotonin type 2, and alpha 2 adrenergic receptors. It is believed that many psychotic illnesses are caused by abnormal communication among nerves in the brain and that by altering communication through neurotransmitters, risperidone can alter the psychotic state. Risperidone was approved by the FDA in December 1993.

PRESCRIPTION: Yes

GENERIC AVAILABLE: Yes, risperidone. No, Risperdal Consta

PREPARATIONS:

  • Tablets: 0.25, 0.5, 1, 2, 3, and 4 mg.
  • Oral solution: 1 mg/mL.
  • Orally disintegrating tablets: 0.25, 0.5, 1, 2, 3, and 4 mg.
  • Powder for injection: 12.5, 25, 37.5, and 50 mg.

STORAGE: Tablets should be kept at room temperature, 15 C to 25 C (59 F to 77 F).

PRESCRIBED FOR: Risperidone is used to treat schizophrenia, bipolar mania alone or combined with lithium (Eskalith, Lithobid) or valproate (Depakene, Depacon) and for the treatment of irritability associated with autistic disorder in children and adolescents. Clinical studies involving small numbers of patients have shown some benefit in using risperidone for stuttering and Tourette's syndrome though these are non FDA-approved uses. Another non-FDA approved use of risperidone is for obsessive-compulsive disorders.

DOSING: Risperidone can be administered once or twice daily. Initial oral dosing for treating schizophrenia is generally 2 mg/day. Dose increases can occur in increments of 1-2 mg/day, as tolerated, to a recommended dose of 4-8 mg/day. In children older than 13 years of age, risperidone should be initiated at 0.5 mg once daily, and can be increased in increments of 0.5 or 1 mg/day, as tolerated, to a recommended dose of 2.5 mg/day. Risperidone can be given with or without meals.

The recommended dose of Risperdal Consta is 12.5 to 25 mg injected into the deltoid or gluteal muscle every two weeks. Dosage should not be adjusted more frequently than every 4 weeks. Patients who have never received risperidone are started on oral risperidone in order to evaluate tolerability. Patients then may be transitioned to Risperdal Consta if oral risperidone is tolerated.

Bipolar mania is treated with oral doses of 2-3 mg/day initially. Dose may be increased by 1 mg/day at every 24 hours up to a dose of 6 mg/day. The dose of Risperdal Consta for bipolar mania is 12.5 to 25 mg injected into the deltoid or gluteal muscle every two weeks. Dosage should not be adjusted more frequently than every 4 weeks.

DRUG INTERACTIONS: Risperidone may interfere with elimination by the kidneys of clozapine (Clozaril), a different type of antipsychotic medication, causing increased levels of clozapine in the blood. This could increase the risk of side effects from clozapine.

Medically Reviewed by a Doctor on 2/21/2014



Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

Pill Finder Tool

Need help identifying pills and medications?
Use the pill identifier tool on RxList.


Back to Medications Index