Generic name: Risperidone.

Risperdal is an antipsychotic. It is thought to work by blocking certain chemicals involved in nerve transmission in the brain.

Quick Facts About Risperdal


Used to treat symptoms of severe mental illness, inсluding schizophrenia.

Risperdal Dosage

Do not change dosage unless directed by your doctor; may cause unwanted side effects.

  • Usual adult dose: 1 milligram taken 2 times per day, increased to 2 milligrams on day 2, and 3 milligrams on day 3. Doctor may increase dosage at weekly intervals. Most people experience maximal effect in the range of 4 to 6 milligrams per day. For individuals with liver or kidney disease — dose is cut in half, with increases by the 1/2 tablet. Seniors — half of usual dose.
  • Usual child dose: not generally prescribed for children.
  • Missed dose: take as soon as possible, unless almost time for next dose. In that case, do not take missed dose; go back to regular schedule. Do not double doses.

Risperdal Side Effects

Overdose symptoms:

drowsiness, low blood pressure, rapid heartbeat, sedation. If you suspect an overdose, immediately seek medical attention.

More common side effects: abdominal pain, abnormal walk, agitation, aggression, anxiety, chest pain, constipation, coughing, decreased activity, diarrhea, difficulty with orgasm, diminished sexual desire, dizziness, dry skin, erection and ejaculation problems, excessive menstrual bleeding, fever, headache, inability to sleep, increased dreaming, increased duration of sleep, indigestion, involuntary movements, joint pain, lack of coordination, nasal inflammation, nausea, overactivity, rapid heartbeat, rash, reduced salivation, respiratory infection, sleepiness, sore throat, tremor, undcractive reflexes, urination problems, vomiting, weight gain.

Less common Risperdal side effects: abnormal vision, back pain, dandruff, difficult or labored breathing, increased saliva, sinus inflammation, toothache.


Inform your doctor before combining Risperdal with:

blood pressure medications such as Aldomet, Procardia, and Vasotec; bromocriptine mesylate (Parlodel); carbamazepine (Tegretol); clozapine (Clozaril) levodopa (Sinemet or Dopar); quinidine (Quinidex). Medications such as Valium, Percocet, Demerol, and Haldol may slow central nervous system and cause other serious side effects. Inform your doctor before taking any other medication.

Alcohol use during Risperdal therapy may cause drowsiness.

Special Cautions

If pregnant or planning to become pregnant, inform your doctor immediately. Not known if Risperdal appears in breast milk.

Seniors are prescribed lower doses. Senior worrier at a higher risk for developing tardive dyskinesia, a condition with symptoms such as involuntary muscle spasms and facial and body twitches.

Not generally prescribed for children.

  • May cause neuroleptic malignant syndrome (NMS), potentially fatal disorder with symptoms such as: muscle stiffness, fast heartbeat or irregular pulse, increased sweating, high fever, high or low blood pressure.
  • May impair your ability to drive a car or operate machinery. Do not take part in any activity that requires alertness.
  • Inform your doctor of any involuntary movement Risperdal increases risk for tardive dyskinesia, a condition with symptoms such as involuntary muscle spasms and facial and body twitches.
  • If sensitive to or allergic to this or other major tranquilizers, should not take.
  • Use with caution if you have: kidney, liver, or heart diseases; seizures; breast cancer; thyroid disorders; or any other diseases affecting metabolism; or if you have exposure to intense heat.
  • Symptoms of overdose may be masked, as well as symptoms of intestinal obstruction, brain tumor, and Reye’s syndrome.
  • May experience dizziness when standing, rapid heartbeat, or fainting at beginning of Risperdal therapy.


HealthSurvey.org provides accurate and independent information prescription pills, over-the-counter medicines and natural products. This material is provided for educational purposes only and is not intended for medical advice, diagnosis or treatment. If you have questions about  dosage, or Risperdal side effects, please contact your healthcare provider