Haldol (Haloperidol Decanoate) - Intramuscular


Haldol (haloperidol) injection can increase the risk of death in older adults (65 and older) with dementia-related psychosis. The Food and Drug Administration (FDA) has assigned a boxed warning to this medication to warn about the safety risks.

What Is Haldol?

Haldol (haloperidol) is an injectable medication in the first-generation, or typical, antipsychotic drug class. You may be prescribed haloperidol if you have a type of schizophrenia that requires a longer course of injectable therapy. This medication is available by prescription and is administered via intramuscular (into the muscle) injection.

First-generation antipsychotics, and more specifically Haldol, work well for schizophrenia by blocking the effects of dopamine.

If you are an older adult with mental health issues related to dementia, Haldol has a warning for an increased risk of death relating to heart disease or infection.

Haldol is a long-acting injection, meaning it slowly releases the drug into the body over time. Other forms of haloperidol injection are available, including an oral version of haloperidol and haloperidol lactate, a short-acting intramuscular injection. Short-acting injections work quickly after administration but require more frequent injections.

Drug Facts

Generic Name: Haloperidol

Brand Name(s): Haldol

Drug Availability: Prescription

Administration Route: Intramuscular

Therapeutic Classification: Typical antipsychotic

Available Generically: Yes

Controlled Substance: N/A

Active Ingredient: Haloperidol

Dosage Form(s): Injection

What Is Haldol Used For?

The FDA approved Haldol to treat schizophrenia.

Haldol should not be used in older adults with dementia-related psychosis, as antipsychotics have been shown to increase the risk of death in this population.

How to Take Haldol

A healthcare provider will administer haloperidol as an injection into your muscle.

When regularly taking this medication, it is important to check your blood work, including a lymphocyte count. Haldol has a risk of decreasing your white and red blood cells, so it's important to ensure they are all within the normal range.


Since Haldol is given in a medical setting, you will likely not need to worry about storage.

However, Haldol should be stored at room temperature (68 F to 77 F), away from light. The medicine does not need to be refrigerated and should not be frozen.

Off-Label Uses

There are no off-label uses (uses other than what the FDA has specifically approved it for) for haloperidol decanoate. However, healthcare providers sometimes prescribe other forms of haloperidol, such as short-acting haloperidol lactate intramuscular injection and oral haloperidol for other health conditions.

Off-label uses for haloperidol lactate injection may include:

  • Agitation and aggression
  • Acute agitation associated with bipolar disorder
  • Nausea and vomiting
  • Delirium

How Long Does Haldol Take to Work?

How quickly Haldol takes to work will be different for everyone. Generally, Haldol takes 24 hours for its antipsychotic effect to start. Even though Haldol works relatively quickly, it may take two to four months for there to be enough in your body to achieve its maximum benefit.

What Are the Side Effects of Haldol?

This is not a complete list of side effects, and others may occur. A healthcare provider can advise you on side effects. If you experience other effects, contact your pharmacist or a healthcare provider. You may report side effects to the FDA at www.fda.gov/medwatch or 800-FDA-1088.

Common Side Effects

The most common side effects of Haldol are: 

  • Extrapyramidal symptoms (involuntary or uncontrolled movements in your body)
  • Tardive dyskinesia (repetitive and involuntary movements that may involve your tongue and face)
  • Spasms of eyeball muscles (oculogyric crisis)

Severe Side Effects

Call your healthcare provider immediately if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects can include the following:

  • Heart-related effects, such as QTc interval-prolongation (abnormalities in the heart’s electrical system) and Torsades de Pointes (a type of fast heart rhythm)
  • Jaundice (yellowing of the skin and whites of the eyes) or worsening liver function
  • Decreased white blood cells (leukopenia)
  • Neuroleptic malignant syndrome, usually seen as an inability to move your muscles and a high fever
  • Allergic reactions, which can cause anaphylaxis, angioedema (swelling), skin reactions, and difficulty breathing

Long-Term Side Effects

One of Haldol's potential long-term side effects is the risk of withdrawal symptoms. If you take Haldol for a long period and stop it suddenly, you may experience tardive dyskinesia, even after discontinuation.

Report Side Effects

Haldol may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your healthcare provider may send a report to the FDA's MedWatch Adverse Event Reporting Program or by phone (800-332-1088).

Dosage: How Much Haldol Should I Take?

A healthcare provider will administer Hadol via intramuscular injection. They will determine the appropriate dosage for you.


Haldol does not typically require special dosing in adults; it is dosed the same even if you have problems with your kidney or liver.

If your child needs this medication, the dose will be adjusted based on height and weight.

Missed Dose

It is important to receive your Haldol injections as scheduled. If you miss a dose, contact your healthcare provider for guidance on what to do.

Overdose: What Happens If I Take Too Much Haldol?

If you receive too much Haldol, you may be more likely to experience the drug's side effects. Most likely, an overdose of Haldol will cause:

  • Severe extrapyramidal symptoms
  • Sedation
  • Low blood pressure

There is no specific antidote. To treat an overdose, you must receive medical advice to treat the symptoms you are experiencing.

What Happens If I Overdose on Haldol?

If you think you or someone else may have overdosed on Haldol, call a healthcare provider or the Poison Control Center (800-222-1222).

If someone collapses or isn't breathing after receiving Haldol, call 911 immediately.


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It is very important that your doctor check your progress while you receive this medicine to allow for changes in your dose and help reduce any unwanted effects.

Do not stop receiving Haldol® suddenly without asking your doctor. You may need to slowly decrease your dose before stopping it completely.

This medicine may cause serious allergic reactions (eg, anaphylaxis, angioedema, dermatitis exfoliative), which can be life-threatening and require immediate medical attention. Tell your doctor right away if you have a cracks in the skin, loss of heat from the body, rash, itching, hoarseness, red, swollen skin, scaly skin, trouble breathing, trouble swallowing, or any swelling of your hands, face, or mouth after receiving this medicine.

Contact your doctor as soon as possible if you have chest pain or discomfort, a fast heartbeat, trouble with breathing, or fever and chills. These may be symptoms of a very serious problem with your heart.

This medicine may cause tardive dyskinesia (a movement disorder). Check with your doctor right away if you have a lip smacking or puckering, puffing of the cheeks, rapid or worm-like movements of the tongue, uncontrolled chewing movements, or uncontrolled movements of the arms and legs.

Check with your doctor right away if you have seizures, difficulty with breathing, a fast heartbeat, a high fever, high or low blood pressure, increased sweating, loss of bladder control, severe muscle stiffness, unusually pale skin, or tiredness. These could be symptoms of a serious condition called neuroleptic malignant syndrome (NMS).

This medicine will often make you sweat less, causing your body temperature to increase. Use extra care not to become overheated during exercise or hot weather while you are receiving this medicine, since overheating may result in heat stroke. Also, hot baths or saunas may make you feel dizzy or faint while you are receiving this medicine.

This medicine may cause some people to become dizzy, drowsy, or may cause trouble with thinking or controlling body movements, which may lead to falls, fractures or other injuries. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.

Dizziness, lightheadedness, or fainting may occur, especially when you get up suddenly from a lying or sitting position. Getting up slowly may help. If this problem continues or gets worse, check with your doctor.

This medicine will add to the effects of alcohol and other CNS depressants (medicines that make you drowsy or less alert). Some examples of CNS depressants are antihistamines or medicine for allergies or colds, sedatives, tranquilizers, or sleeping medicine, prescription pain medicine or narcotics, medicine for seizures or barbiturates, muscle relaxants, or anesthetics, including some dental anesthetics. Check with your doctor before taking any of the above while you are receiving this medicine.

Haloperidol can temporarily lower the number of white blood cells in your blood, increasing the chance of getting an infection. If you can, avoid people with infections. Check with your doctor right away if you think you are getting an infection, or if you have a fever or chills, a cough or hoarseness, lower back or side pain, or painful or difficult urination.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

What Are Reasons I Shouldn’t Take Haldol?

You should not receive Haldol if you:

  • Have experienced severe toxic central nervous system depression
  • Are in a coma
  • Have Parkinson’s disease
  • Have had an allergic reaction to haloperidol

What Other Medications Interact With Haldol?

Haldol can interact with other medications. Before starting treatment, tell your healthcare provider about any other medicines you take or plan to take, including over-the-counter (OTC) nonprescription products, vitamins, herbs, supplements, and plant-based medicines.

Taking lithium, another medication used for behavioral disorders, with Haldol can cause weakness, fatigue, confusion, and other symptoms. You should also avoid taking Haldol with opioids and alcohol, as it can increase the sedative effects.

Other medications that can interact with Haldol include:

Talk with your pharmacist or healthcare provider for more detailed information about medication interactions with Haldol.

What Medications Are Similar?

Other antipsychotic medications that can be used for schizophrenia include:

Frequently Asked Questions

  • How expensive is Haldol? Is there a way to get help paying for it?

    Haloperidol is a medication available under the brand name Haldol. It is also available as a generic. The price will depend on the insurance that you have. If you need help paying for it, the manufacturer may offer financial assistance. You can visit NeedyMeds to help you find assistance programs. If cost is a concern for you, talk to your healthcare provider or pharmacist about other financial assistance programs or nonprofits to help you pay for your medications. 

  • How can I manage the side effects associated with Haldol?

    To prevent adverse reactions, your healthcare provider will generally increase your dose slowly to make sure you can tolerate it. Tell your healthcare provider if you are experiencing side effects related to your medication.

  • What else should I do to manage my symptoms?

    If you are struggling with schizophrenia, the American Psychiatric Association also recommends behavioral or cognitive therapy.

How Can I Stay Healthy While Taking Haldol?

To stay healthy while taking Haldol, it is important to follow the medical advice of your healthcare team. Avoid other substances or medications that may interact negatively with Haldol. Your healthcare provider can provide more detailed information on potential interactions.

Watch for the development of side effects related to your treatment. This can include muscle-related effects, such as restlessness, stiffness, tremors, or uncontrolled movements. Potentially serious side effects can cause a high fever, muscle stiffness, and heart-related side effects, such as a fast heart rate. Contact your healthcare provider immediately if you experience any of these symptoms.

Along with taking this medication as prescribed, it's important you get plenty of rest, stay hydrated, and eat a healthy diet as instructed by your healthcare provider.

Medical Disclaimer

Verywell Health's drug information is meant for educational purposes only and is not intended to replace medical advice, diagnosis, or treatment from a healthcare provider. Consult your healthcare provider before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

The author would like to recognize and thank Chong Yol Gacasan Kim for contributing to this article.

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Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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