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Drugs reference index «Risperidone»



Brand names: Risperdal M-Tab, Risperdal

Why is Risperidone prescribed?

Risperdal is prescribed for the treatment of schizophrenia, a severe mental disorder that can cause delusions (false beliefs) and hallucinations. It is also used for the short-term treatment of mania associated with bipolar disorder. Risperdal is thought to work by muting the impact of dopamine and serotonin, two of the brain's key chemical messengers.

Most important fact about Risperidone

Risperdal may cause tardive dyskinesia, a condition that causes involuntary muscle spasms and twitches in the face and body. This condition can become permanent and is most common among older people, especially women. Tell your doctor immediately if you begin to have any involuntary movement. You may need to discontinue Risperdal therapy.

How should you take Risperidone?

Do not take more or less of Risperidone than prescribed. Higher doses are more likely to cause unwanted side effects.

Risperdal may be taken with or without food.

Risperdal oral solution comes with a calibrated pipette to use for measuring. The oral solution can be taken with water, coffee, orange juice, and low-fat milk, but not with cola drinks or tea.

Risperdal orally disintegrating tablets (M-Tabs) come in blister packs and should not be removed from the package until you are ready to take them. When it's time for your dose, use dry fingers to peel back the foil of the blister pack to remove the tablet; do not push the tablet through the foil because this could damage the tablet. Immediately place the tablet on your tongue. The medication dissolves in the mouth quickly and can be swallowed with or without liquid. You should not split or chew the orally disintegrating tablets.

  • If you miss a dose...Take it as soon as you remember. If it is almost time for your next dose, skip the one you missed and go back to your regular schedule. Do not take 2 doses at once.
  • Storage instructions...Store at room temperature. Protect tablets from light and moisture; protect oral solution from light and freezing.

What side effects may occur?

Side effects cannot be anticipated. If any develop or change in intensity, tell your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking Risperdal.

  • Side effects may include:Agitation, anxiety, constipation, dizziness, hallucination, headache, indigestion, insomnia, rapid or irregular heartbeat, restlessness, runny nose, sleepiness, vomiting, weight change

Why should Risperidone not be prescribed?

If you are sensitive to or have ever had an allergic reaction to Risperdal or other major tranquilizers, you should not take Risperidone.

Risperdal should not be used to treat elderly patients who have dementia because the drug could increase the risk of stroke.

Special warnings about Risperidone

You should use Risperdal cautiously if you have kidney, liver, or heart disease, seizures, breast cancer, thyroid disorders, or any other diseases that affect the metabolism (conversion of food into energy and tissue). Use caution, too, if you've had a stroke or mini-strokes, suffer from fluid loss or dehydration, or expect to be exposed to extremes of temperature.

Be aware that Risperdal may mask signs and symptoms of drug overdose and of conditions such as intestinal obstruction, brain tumor, and Reye's syndrome (a dangerous neurological condition that may follow viral infections, usually occurring in children). Risperdal can also cause difficulty when swallowing, which in turn can cause a type of pneumonia.

Risperdal may cause neuroleptic malignant syndrome (NMS), a condition marked by muscle stiffness or rigidity, fast heartbeat or irregular pulse, increased sweating, high fever, confusion, dulled pain, falling/physical instability, and high or low blood pressure. Unchecked, this condition can prove fatal. Call your doctor immediately if you notice any of these symptoms. Risperdal therapy should be discontinued.

Certain antipsychotic drugs, including Risperdal, are associated with an increased risk of developing high blood sugar, which on rare occasions has led to coma or death. See your doctor right away if you develop signs of high blood sugar, including dry mouth, unusual thirst, increased urination, and tiredness. If you have diabetes or have a high risk of developing it, see your doctor regularly for blood sugar testing.

People at high risk for suicide attempts will be prescribed the lowest dose possible to reduce the risk of intentional overdose.

This drug may impair your ability to drive a car or operate potentially dangerous machinery. Do not participate in any activities that require full alertness if you are unsure of your ability.

Risperdal is prescribed for the short-term treatment of rapid-onset bipolar mania; it is not approved for preventing future episodes. The effectiveness of the drug for treating mania for more than 3 weeks has not been studied.

Risperdal can cause orthostatic hypotension (low blood pressure when rising to a standing position), with dizziness, rapid heartbeat, and fainting, especially when you first start to take it. If you develop this problem, report it to your doctor. He can adjust your dose to reduce the symptoms.

Be sure to tell your doctor if you have phenylketonuria and must avoid the amino acid phenylalanine, since Risperdal M-Tabs contains this substance.

The safety and effectiveness of Risperdal have not been studied in children.

Possible food and drug interactions when taking Risperidone

If Risperdal is taken with certain other drugs, the effects of either can be increased, decreased, or altered. It is especially important to check with your doctor before combining Risperdal with the following:

Blood pressure medicinesBromocriptine mesylateCarbamazepineClozapineFluoxetineLevodopaParoxetinePhenobarbitalPhenytoinQuinidineRifampinValproic acid

Risperdal tends to increase the effect of blood pressure medicines.

You may experience drowsiness and other potentially serious effects if Risperdal is combined with alcohol and other drugs that slow the central nervous system such as alprazolam and narcotic painkillers.

Check with your doctor before taking any new medications.

Special information if you are pregnant or breastfeeding

The safety and effectiveness of Risperdal during pregnancy have not been adequately studied. If you are pregnant or plan to become pregnant, tell your doctor immediately. Risperdal makes its way into breast milk, so women taking Risperdal must avoid breastfeeding.

Recommended dosage for Risperidone



Doses of Risperdal can be taken once a day, or divided in half and taken twice daily. The usual dose on the first day is 2 milligrams or 2 milliliters of oral solution. On the second day, the dose increases to 4 milligrams or milliliters, and on the third day rises to 6 milligrams or milliliters. Further dosage adjustments can be made at intervals of 1 week. Over the long term, typical daily doses range from 2 to 8 milligrams or milliliters.



The recommended starting dose is 2 to 3 milligrams (or milliliters of oral solution) per day, given as a single dose. If needed, the doctor will adjust the dose by 1 milligram at intervals of at least 24 hours. The effective dosage range is 1 to 6 milligrams a day.


The doctor may prescribe lower doses if you are weak, elderly, have liver or kidney disease, or have a high risk for low blood pressure. The usual starting dose is 0.5 milligram (or 0.5 milliliter of oral solution) twice a day. The doctor may switch you to a once-a-day dosing schedule after the first 2 to 3 days of treatment.

If needed, each dose may be increased by increments of no more than 0.5 milligram. Increases to dosages above 1.5 milligrams twice a day should generally me made at intervals of at least 1 week.

You may also need your Risperdal dose adjusted if you're taking certain medications, including Dilantin, Paxil, phenobarbital, Prozac, Rifadin, and Tegretol.


Any medication taken in excess can have serious consequences. If you suspect an overdose of Risperdal, seek medical attention immediately.

  • Symptoms of Risperdal overdose may include:Drowsiness, low blood pressure, rapid heartbeat, sedation
  • Risperidone MedFacts Consumer Leaflet (Wolters Kluwer)
  • Risperidone Prescribing Information (FDA)
  • Risperidone Professional Patient Advice (Wolters Kluwer)
  • 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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