Generic name: haloperidol (injection) [ HAL-oh-PER-i-dol ]
Other brand names of haloperidol (injection) include Haldol Decanoate, Haldol injection
Drug class: Miscellaneous antipsychotic agents

Medically reviewed by Drugs.com on Aug 16, 2023. Written by Cerner Multum.

What is Haldol?

Haldol is an antipsychotic medicine that is used to treat schizophrenia.

Haldol is also used to control motor and speech tics in people with Tourette's syndrome.

Haldol is sometimes used in people who are unable to take the medicine by mouth.

Haldol may also be used for purposes not listed in this medication guide.

Haldol side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

High doses or long-term use of haloperidol can cause a serious movement disorder that may not be reversible. The longer you use Haldol, the more likely you are to develop this disorder, especially if you are a diabetic or an older adult.

Haldol may cause serious side effects. Call your doctor at once if you have:

• uncontrolled muscle movements in your face (chewing, lip smacking, frowning, tongue movement, blinking or eye movement);

• rapid changes in mood or behavior;

• fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness (like you might pass out);

• cough with mucus, chest pain, feeling short of breath;

• lack of energy, decreased thirst;

• muscle spasms in your neck, tightness in your throat, trouble swallowing;

• low white blood cell counts--fever, chills, mouth sores, skin sores, sore throat, cough, trouble breathing; or

• severe nervous system reaction--very stiff (rigid) muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, feeling like you might pass out.

Serious side effects may be more likely in older adults.

Common side effects of Haldol may include:

• drowsiness;

• neck stiffness;

• tremors; or

• involuntary muscle movements.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Related/similar drugs

Warnings

Haldol is not approved for use in older adults with dementia-related psychosis.

Before taking this medicine

You should not receive Haldol if you are allergic to Haldol, or if you have:

• Parkinson's disease;

• dementia with Lewy bodies;

• a peanut allergy (this medicine contains sesame oil); or

• certain conditions that affect your central nervous system (such as severe drowsiness, or slowed thinking caused by taking other medicines or drinking alcohol).

Haldol may increase the risk of death in older adults with dementia-related psychosis and is not approved for this use.

Tell your doctor if you have ever had:

• heart problems, angina (chest pain);

• long QT syndrome (in you or a family member);

• low blood pressure;

• a seizure;

• low white blood cell (WBC) counts;

• a thyroid disorder; or

• an electrolyte imbalance (such as low blood levels of potassium or magnesium).

Using antipsychotic medicine in the last 3 months of pregnancy may cause serious problems in the newborn. If you get pregnant, tell your doctor right away. Do not stop the medicine without your doctor's advice.

You should not breastfeed while using Haldol.

How is Haldol given?

You may be given oral Haldol to take by mouth for a short time before you are treated with this medicine.

Haldol is injected into a muscle by a healthcare provider, usually once every 3 to 4 weeks as needed.

If you use this medicine long-term, you may need frequent medical tests.

Do not stop using Haldol suddenly after long-term use, or you could have unpleasant withdrawal symptoms. Ask your doctor how to safely stop using this medicine.

What happens if I miss a dose?

Call your doctor for instructions if you miss an appointment for your Haldol.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222 if you have overdose symptoms (extreme drowsiness, severe tremors or muscle stiffness, weak or shallow breathing, fainting). An overdose of haloperidol can be fatal.

What should I avoid while receiving Haldol?

Avoid driving or hazardous activity until you know how Haldol will affect you. Dizziness or drowsiness can cause falls, accidents, or severe injuries.

Avoid drinking alcohol. Dangerous side effects could occur.

Avoid becoming overheated or dehydrated during exercise and in hot weather. You may be more prone to heat stroke while you are using Haldol.

What other drugs will affect Haldol?

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Haldol can cause a serious heart problem. Your risk may be higher if you also use certain other medicines for infections, asthma, heart problems, high blood pressure, depression, mental illness, cancer, malaria, or HIV.

Using Haldol with other drugs that make you drowsy can worsen this effect. Ask your doctor before using opioid medication, a sleeping pill, a muscle relaxer, or medicine for anxiety or seizures.

Tell your doctor about all your other medicines, especially:

• lithium;

• rifampin;

• medicine to treat Parkinson's disease;

• seizure medicine; or

• a blood thinner--warfarin, Coumadin, Jantoven.

This list is not complete. Other drugs may affect Haldol, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Frequently asked questions

• What drugs cause tardive dyskinesia?

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

Copyright 1996-2025 Cerner Multum, Inc. Version: 6.01.