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Traditional Antipsychotics

Traditional antipsychotics may also be referred to as “first-generation antipsychotics.”

Chlorpromazine (Largactil®)   Haloperidol (Haldol, Haldol LA®)   Loxapine (Loxapac®)   Methotrimeprazine (Nozinan®)   Zuclopenthixol (Clopixol®)

What is this medication used for?

Traditional antipsychotics are medications used to treat schizophrenia and other thought disorders, bipolar disorder, tics and Tourette syndrome, irritability associated with autism spectrum disorder and conduct disorder. They may also help treat symptoms associated with some anxiety and sleep disorders.

When potential benefits outweigh risks, traditional antipsychotics may be prescribed “off-label.” 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 medicationsinteract with traditional antipsychotics. Your doctor mayadjust medication doses or monitor for side effects
  • Have a history of epilepsy, diabetes or have ever had aseizure, kidney or liver disease, a bowel obstruction orglaucoma
  • Have a history (or family history) of diabetes, heart disease,arrhythmia or “familial long QT syndrome”
  • Miss a menstrual period, are pregnant, breast-feeding orplanning a pregnancy
  • Use alcohol or drugs. Taking traditional antipsychotics together with certain substances may cause a bad reaction. Learn more at

When will the medication start to work?

When treating schizophrenia, it may take 3 to 6 weeks or longer before the benefits are noticeable. If you are taking this medication to help with symptoms of mood disturbances, you may notice some changes in the first 1 to 2 weeks. You (or your family members) may notice clearer thoughts, less moodiness, anger, irritability, or explosive behaviour. If you experience seeing, hearing or feeling things that are not there, this may also decrease or stop entirely.

It is important that you continue taking this 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, or if side effects are too bothersome. 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.

Possible common or serious side effects:

Side effects may be more common when first starting a medication or after a dose increase. If any side effect concerns you, talk with your doctor, nurse or pharmacist.

  • Dizziness, drowsiness or headache
  • Feelings of agitation or restlessness
  • Stomach ache or constipation
  • Increased appetite or weight gain
  • Blurred vision or dry mouth
  • Muscle stiffness or muscle spasm
  • Increased blood glucose or cholesterol levels

Contact your doctor immediately if you experience:

  • Unexplained rash, seizure, fever or excessive sweating
  • Fainting, feeling lightheaded or difficulty with balance
  • Breast tenderness or swelling (males and females)
  • Feelings of restlessness, fast or irregular heartbeat
  • Shaking, pain or weakness
  • Unusual movements of fingers, toes, neck, lips or tongue
  • Unexplained confusion

How do I take this medication?

Some people may only need to take a traditional antipsychotic occasionally or on an as-needed basis, while other patients may take it regularly. If you take it regularly, traditional antipsychotics are usually taken once daily or several times a day, at the same time(s) each day. You may take these medications with or without food. Usually, you will start with a low dose and slowly increase this dose over several days or weeks, based on how you tolerate it.

There are several forms of traditional antipsychotics: tablets, fast-acting injections and long-acting injections. Some traditional antipsychotics will not be available in all forms.

For a short-acting injection, a doctor or nurse will give this into a large muscle as needed. For a long-acting injection, a doctor or nurse will give this into a large muscle every 1 to 4 weeks.

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

  • When you take this medications, 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 taking these medications, 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.
  • Traditional antipsychotics can cause a rare side effect called “tardive dyskinesia.” Symptoms include involuntarymovements 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.
  • Traditional antipsychotics can cause a rare side effect called“neuroleptic malignant syndrome.” Symptoms include severe muscle stiffness, high fever, sweating, increased or irregular heartbeat and decreased blood pressure.

What special instructions should I follow while using this medication?

  • Keep all appointments with your doctor and the lab. Yourdoctor may order lab tests to check how you are respondingand monitor for side effects.
  • Try to keep a healthy, well-balanced diet and exerciseregularly. Some people may gain weight as a result ofincreased appetite.
  • Wear sunscreen and sunglasses as these medicationsincrease sensitivity to the sun.
  • Do not allow anyone else to use your medication.

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

If you take this medication regularly and forget to take a dose, take the missed dose as soon as you remember. However, if it is within 4 hours of your next scheduled dose, skip the missed dose and continue with your regular schedule. DO NOT double your next dose to try to ‘catch up’.

If you are receiving a long-acting injection and you miss your dose, make an appointment with your doctor for injection administration.

How well does the medication work in children and adolescents?

Evidence supports the use of traditional antipsychotics in children and adolescents. Some traditional antipsychotics have been shown to be better than placebo (an inactive pill) for treatment of schizophrenia. In bipolar disorder, there is evidence that symptoms of mood disturbance are reduced more by a traditional antipsychotic compared to placebo.

There is also evidence supporting the use of certain traditional antipsychotics (such as haloperidol, pimozide) in children and adolescents with tic disorders. Learn more about pimozide use:

How does this medication work?

Traditional antipsychotics affect actions of the brain chemical dopamine. The exact way that antipsychotic medications improve symptoms of schizophrenia, bipolar disorder, irritability of autism, Tourette syndrome, conduct disorder and other conditions is not known.

How do I store this medication?

Keep these medications in the original container, stored at room temperature away from moisture and heat and protected from light. Keep these medications out of reach and sight of children.

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 with schizophrenia or tic disorders need to take these medications for several months. This allows time for symptoms to stabilize and for function to improve. Your doctor will discuss the benefits and risks of taking traditional antipsychotics with you. At this time, you can also discuss how long you might need to take the medication.

If you have schizophrenia and you tolerate this medication well, you may be asked to take this medication on an ongoing basis. Continuing treatment will significantly decrease the chance that your symptoms will return.

Do not increase, decrease, or stop taking these medications without talking with your doctor. If you stop taking the medication suddenly, it is possible that your symptoms may return 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.

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