Sounds like 'ris-perry-done'

Easy-to-read medicine information about risperidone – what it is, how to take risperidone safely and possible side effects.

Type of medicine Also called
  • Belongs to a group of medicines known as antipsychotics 
  • Risperdal®
  • Ridal®
  • Dr Reddy's Risperidone®
  • Apo-Risperidone®
Oral liquid
  • Risperdal®
  • Risperon®
  • Risperdal Consta®

What is risperidone?

  • Risperidone is used to treat some types of mental illness such as schizophrenia and symptoms of psychoses such as hearing voices, seeing, feeling or sensing things that are not there, unpleasant thoughts, feeling paranoid, feeling that other people can read your thoughts, being withdrawn or lacking in motivation.
  • Risperidone can also be used to treat mood disorder (bipolar disorder), and mania — feelings of over excitement, elation, agitation.
  • It is also used in dementia, for agitation, restlessness, aggression and hallucinations (hearing or seeing things that aren't there such as hearing voices).
  • Risperidone works by helping to restore the balance of certain natural chemicals in the brain (neurotransmitters).
  • It belongs to a group of medicines called antipsychotics.
  • Risperidone is available as tablets or a liquid solution.
  • It is also available as an injection. The long-acting or depot injection is an option when your symptoms have settled by taking tablets or liquid solution.      


  • The dose of risperidone will be different for different people. Your doctor will usually start you on a low dose and increase the dose gradually. This allows your body to get used to the medicine and reduce unwanted side effects.
  • The dose of risperidone depot or long-acting injection is also different for different people, depending on your condition and your response to the medication. It is usually given every 2 weeks. 
  • Always take your risperidone exactly as your doctor has told you. The pharmacy label on your medicine will tell you how much risperidone to take, how often to take it and any special instructions.

How to take risperidone

Risperidone tablets and liquid solution

  • Take risperidone tablets with a glass of water.
  • Risperidone liquid should be measured carefully with the syringe provided. The liquid may be placed in a small cup and mixed with water, orange juice, or low-fat milk.
  • Risperidone is not affected by food, so you can take it before or after food. Try taking risperidone with food if it makes you feel sick (nausea).
  • Limit or avoid drinking alcohol while you are taking risperidone. Alcohol may increase your chance of side effects such as drowsiness.
  • If you forget to take your dose, take it as soon as you remember that day. But, if it is nearly time for your next dose, just take the next dose at the right time. Do not take double the amount.
  • Keep taking risperidone every day. It usually takes a few weeks to start working and it can take several months before you feel the full benefits.
  • Do not stop taking risperidone suddenly as your symptoms may return if stopped too early; speak to your doctor or nurse before stopping.

Risperidone long-acting (depot) injection

  • Risperidone is also available as an injection.
  • Risperidone depot injection is given as a shot into one of your muscles, usually in the arm or buttock (bottom).
  • This injection is given by a nurse or other trained health professional, in a clinic, community health center, or hospital.
  • The injection site should change every 2 weeks to the other arm or buttock, so it’s not in the same place all the time.
  • As a routine, you will be observed for about 2 hours after each injection. This is because it can make you feel tired or dizzy after it is given. You will be advised not to drive or use tools or machines for the remainder of the day.


Risperidone may cause changes in your blood sugar level, your cholesterol level and in your heart function. To keep an eye out for these effects, your doctor will monitor your physical health. You will have your weight measured regularly. You may be sent for tests such as blood tests to monitor your blood, kidneys, liver, cholesterol and glucose levels. You may also have your blood pressure measured and be required to undergo an ECG test to assess your heart rate.

Possible side effects

Like all medicines, risperidone can cause unwanted side effects, although not everyone gets them. Often unwanted side effects improve as your body gets used to the new medicine.

Side effects What should I do?
  • Feeling sleepy, drowsy or tired
  • It can last a few hours after the dose.  
  • Don’t drive or operate machinery.  
  • Ask your doctor if you can take you medicine at a different time.
  • Avoid drinking alcohol.
  • Tell your doctor if troublesome.
  • Feeling dizzy
  • This usually only happens when you start your medication.
  • It should wear off in a few weeks.
  • Try not to stand up too quickly. You are at risk of falls.
  • If you feel dizzy, don't drive.
  • Weight gain by eating more
  • A diet full of vegetables and fibre may help prevent weight gain.
  • Limit sugary or fatty foods.
  • Speak with your doctor if your weight becomes troublesome.
  • Feeling shaky, feeling restless (cannot sit still)
  • Eyes or tongue may move on their own
  • This is a well known side effect and is not dangerous.
  • Tell your doctor if troublesome
  • Headache
  • Try paracetamol.  Check that this can be taken with any other medicines you may take.
  • Signs of changes in hormones such as, in women, it can affect breasts (including milk being leaked) and irregular or no periods.
  • In men it can cause impotence (trouble maintaining an erect penis) and chest changes.
  • These changes are due to raised levels of a hormone called prolactin, and it can be very distressing.
  • Discuss with your doctor.
  • Signs of diabetes such as you may lose weight, pass lots of urine, and feel thirsty and hungry all the time.
  • Tell your doctor if you get these symptoms. You can then have some simple tests to see if you are developing diabetes.


  • Risperidone may interact with some medicines and herbal supplements, so check with your doctor or pharmacist.
  • Risperidone may interact with some medicines that are available without a prescription, such as:
    • cold and flu preparations such as Coldrex®, Dimetapp PE®
    • anti-nausea medication such as Buccastem®, Scopoderm®
    • anti-allergy medication

Learn more

Medsafe Consumer Information Sheet


Risperdal Consta

Credits: Sandra Ponen, Pharmacist. Reviewed By: Nicola Rowbottom, Pharmacist, South Canterbury Last reviewed: 13 Oct 2016