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Haloperidol decanoate intramusc.

Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.


(hal-oh-PAIR-ih-doll deck-ah-NO-ate)



This medication is used to treat symptoms of certain types of mental conditions (e.g., schizophrenia).

How To Use

This medication is injected into a muscle. It is not to be injected into a vein. This medication is the long-acting form of haloperidol and is usually administered once every 4 weeks. This medication must be used as prescribed. Do not stop using this drug suddenly without consulting your doctor. Some conditions may worsen if the medication is suddenly stopped.

Side Effects

This drug may cause drowsiness, dizziness, blurred vision, stomach upset, loss of appetite, headache, drooling, dry mouth, sweating, sleep disturbances or restlessness. If these effects persist or worsen, notify your doctor promptly. Unlikely but report: chest pain, aching muscles and joints, unusual bleeding or bruising, tremors, skin rash, involuntary movements of the face/tongue/mouth (chewing movements, puckering or twitching tongue). Tell your doctor immediately if any of these highly unlikely but very serious side effects occur: fainting, fast/irregular heartbeat. In the unlikely event you have an allergic reaction to this drug, seek immediate medical attention. Symptoms of an allergic reaction include: rash, itching, swelling, dizziness, trouble breathing. If you notice other effects not listed above, contact your doctor or pharmacist.


Tell your doctor your medical history, especially of: Parkinson's disease, liver or kidney problems, heart disease, thyroid disease, blood vessel disease, glaucoma, enlarged prostate, difficulty urinating, allergies, asthma, emphysema or other lung disease, seizures, alcohol use. Before having surgery (including dental surgery) with a general anesthetic, tell your doctor you are using haloperidol. Use caution performing tasks that require alertness. Limit your intake of alcohol as alcohol adds to the drowsiness caused by haloperidol. Haloperidol should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor. This drug is excreted into breast milk. Do not breast-feed while using this medication. Haloperidol may make your skin more sensitive to the sun. If you become sun sensitive, stay out of the sun and wear protective clothing, sunscreen and sunglasses. Avoid exposure to extreme heat or cold. Haloperidol reduces your ability to regulate body temperature which could result in overheating or severe chilling. Do not swim in cold water.

Drug Interactions

Tell your doctor of all medications you may use (both prescription and nonprescription), especially of: sedatives, sleeping pills, narcotic pain medication, muscle relaxants, certain antihistamines (e.g., diphenhydramine), antidepressants, barbiturates, fluoxetine, carbamazepine, guanethidine, lithium, cabergoline, methyldopa, phenytoin. Report other drugs which affect the heart rhythm (QTc prolongation), such as: dofetilide, pimozide, quinidine, sotalol, procainamide, sparfloxacin, "water pills" (diuretics such as furosemide or hydrochlorothiazide). Ask your doctor or pharmacist for more details. Use of alcohol can lead to extreme drowsiness. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include agitation, very dry mouth, unusual drowsiness or deep sleep, slow or shallow breathing, rapid or irregular pulse, and muscle weakness, rigidity, or tremor.


Do not share this medication with others.

Missed Dose

If you miss a dose, contact your doctor. Do not "double-up" the dose to catch up.


Store at room temperature between 59 and 86 degrees F (15 to 30 degrees C) away from moisture and sunlight. Do not refrigerate or freeze.