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Long-Acting Injectable Antipsychotics

Aripiprazole (Abilify Maintena®) Paliperidone (Invega Sustenna®, Invega Trinza®) Risperidone (Risperdal Consta®)

What is this medication used for?

Long-Acting Injectable Antipsychotics (LAIAs) are not approved by Health Canada for use in children and adolescents.

However, they may be used to treat schizophrenia and bipolar disorder. When potential benefits outweigh risks, LAIAs may be prescribed “off-label.”

LAIAs are injected into a muscle every few weeks to months. Compared to antipsychotics taken by mouth, LAIAs are especially helpful for people who are not able or willing to take oral medication on a regular basis. Learn more about off-label medication use:

Tell your doctor or pharmacist if you:

  • Have allergies or bad reactions to a medication
  • Take (or plan to take) other prescription or non- prescription medications, including natural medicines. Some medications interact with LAIAs. Your doctor may adjust medication doses or monitor for side effects
  • Have a history (or family history) of kidney or liver disease, seizures, bowel obstruction, diabetes or glaucoma
  • Have a history (or family history) of heart disease, arrhythmia or “familial long QT syndrome”
  • Miss a menstrual period, are pregnant, breast-feeding or planning a pregnancy
  • Use alcohol or drugs. Taking LAIAs together with certain substances may cause a bad reaction. Learn more at

When will the medication start to work?

It may take several weeks before the benefits of LAIAs become noticeable. You (or your family members) may notice clearer thoughts, less moodiness, anger, irritability, tics or explosive behaviour.

It is important that you continue receiving the medication regularly even if you are feeling well, as it can prevent symptoms from returning. Talk with your doctor if you feel this medication has not been helpful. Your doctor may recommend switching you to a different medication.

This medication is not addictive. Do not stop taking it before talking to your doctor.

How do I take this medication?

LAIAs are usually administered into a large muscle in the upper arm or buttock by a doctor or nurse. Do not rub the injection site after receiving an injection. Before starting a LAIA, you may be asked to take the oral form of this medication for a few weeks to make sure you tolerate it well. After your first risperidone or aripiprazole injection, you may be asked to continue taking the oral medication for a few more weeks to give the injection time to start working.

Risperidone is typically administered every 2 weeks. Aripiprazole is typically administered every month. Paliperidone may be administered every month (Invega Sustenna®) or every 3 months (Invega Trinza®). You may be given two injections (1 week apart) when starting paliperidone monthly injections. You must receive at least 4 monthly Invega Sustenna® injections before becoming eligible to receive Invega Trinza® every 3 months.

Possible common or serious side effects:

Side effects may be more common when starting a medication or after a dose increase. Talk to your doctor, nurse or pharmacist if any side effect concerns you.

  • Pain, swelling or redness at the injection site
  • Dizziness, drowsiness or headache
  • Feelings of agitation or restlessness
  • Stomach ache or constipation
  • Increased appetite or weight gain
  • Fast or irregular heartbeat
  • Increased blood glucose or cholesterol level

Contact your doctor immediately if you experience:

  • Unexpected rash, seizure, fever or excessive sweating
  • Fainting, feeling lightheaded or difficulty with balance
  • Breast tenderness or swelling (in males and females), or changes in menstrual cycle
  • Frequent urination accompanied by excessive thirst
  • Shaking, muscle spasm/stiffness, pain or weakness
  • Unusual movements of fingers, toes, neck, lips or tongue
  • Thoughts of hurting yourself, suicide, increased hostility, or worsening symptoms

What precautions should my doctor and I be aware of when taking this medication?

  • While on a LAIA, your body may have difficulty maintaining a normal body temperature. Drink enough fluids to avoid becoming dehydrated. Avoid doing a lot of physical activity on hot days.
  • While on a LAIA, if you feel dizzy, drowsy or slowed down, do not drive a car or operate heavy machinery. Alcohol could make this worse. Try to avoid alcohol while taking this medication.
  • Antipsychotics can cause a rare side effect called “tardive dyskinesia.” Symptoms include involuntary movements of the lips, tongue, toes, hands or neck. Stopping or switching this medication at first signs will decrease the chances this side effect will continue. These movements may become permanent without a medication change.
  • Antipsychotics can cause a rare side effect called “neuroleptic malignant syndrome.” Symptoms include severe muscle stiffness, high fever, sweating, increased or irregular heartbeat and increased blood pressure.

What special instructions should I follow while using this medication?

  • Keep all appointments with your doctor and the lab. Your doctor may order lab tests to check how you are responding and monitor for side effects.
  • Try to keep a healthy, well-balanced diet and exercise regularly. Some people may gain weight as a result of increased appetite.

What should I do if I forget to take a dose of this medication?

If you miss a dose of your LAIA, make an appointment with your doctor for injection administration.

How do I store this medication?

Typically, you will not need to store LAIAs at home. If needed, aripiprazole and paliperidone should be stored at room temperature, and risperidone (Risperdal Consta®) needs to be stored in the fridge (between 2-8 oC). Keep this medication in the original container, out of reach and sight of children.

TIP: For information on specific antipsychotics, visit:

How does this medication work?

Antipsychotics affect actions of the brain chemicals dopamine and serotonin. The exact way that antipsychotic medications improve symptoms of schizophrenia, bipolar disorder and other conditions is not known.

Once a LAIA is injected, the medication will form a small harmless lump in the muscle. Over weeks to months, steady amounts of the medication will be released into the rest of your body. This allows your body to receive a consistent amount of the medication.

How well does the medication work in children and adolescents?

Evidence supports the use of LAIAs in children and adolescents. LAIAs are as effective as antipsychotics taken by mouth. However, LAIAs have been shown to reduce rates of relapse and hospitalization in adults compared to antipsychotics taken by mouth. This is due to a steady and controlled release of the medication into the body, and not having to worry about missed or late doses for those unwilling or unable to take oral medications on a regular basis.

How long should I take the medication for?

This depends on the symptoms you have, how frequently they occur, and how long you have had them. Most people who are treated with an LAIA will receive it for several years. Continuing treatment will significantly decrease the chance that your symptoms will return. Your doctor can discuss the benefits and risks of using a LAIA with you.

Do not stop receiving this medication without talking with your doctor. If you stop receiving this medication suddenly, it is possible that your symptoms may return gradually or you may have a bad reaction.

TIP: Use the Kelty Mental Health Antipsychotic Monitoring Form for Children and Adolescents to help measure your progress on this medication.

Also see the Kelty Mental Health document Atypical Antipsychotics & Metabolic Monitoring.

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