Haldol Side Effects

Generic name: haloperidol

Medically reviewed by Drugs.com. Last updated on Oct 4, 2023.

Note: This document provides detailed information about Haldol Side Effects associated with haloperidol. Some dosage forms listed on this page may not apply specifically to the brand name Haldol.

Applies to haloperidol: oral solution, oral tablet.

Other dosage forms:

• intramuscular oil, intramuscular solution

Precautions

Your doctor should check your progress at regular visits, especially during the first few months of treatment with this medicine. The amount of haloperidol (the active ingredient contained in Haldol) you take may be changed to meet the needs of your condition and to prevent side effects.

Do not Stop taking haloperidol without checking first with your doctor. Your doctor may want you to gradually reduce the amount you are taking before stopping completely. This will allow your body time to adjust and help avoid a worsening of your medical condition.

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 using 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. Even if you take haloperidol at bedtime, you may feel drowsy or less alert on arising. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or not alert.

Dizziness, lightheadedness, or fainting may occur, especially when you get up 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 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 taking this medicine, since overheating may result in heat stroke. Also, hot baths or saunas may make you feel dizzy or faint while you are using this medicine.

Haloperidol may cause your skin to be more sensitive to sunlight than it is normally. Exposure to sunlight, even for brief periods of time, may cause a skin rash, itching, redness or other discoloration of the skin, or a severe sunburn. When you begin taking this medicine:

• Stay out of direct sunlight, especially between the hours of 10:00 a.m. and 3:00 p.m., if possible.
• Wear protective clothing, including a hat or sunglasses.
• Apply a sun block product that has a sun protection factor (SPF) of at least 15. Some patients may require a product with a higher SPF number, especially if they have a fair complexion. If you have any questions about this, check with your doctor.
• Apply a sun block lipstick that has an SPF of at least 15 to protect your lips.
• Do not use a sunlamp or tanning bed or booth.

If you have a severe reaction from the sun, check with your doctor.

Haloperidol may cause dry mouth. For temporary relief, use sugarless candy or gum, melt bits of ice in your mouth, or use a saliva substitute. However, if your mouth continues to feel dry for more than 2 weeks, check with your medical doctor or dentist. Continuing dryness of the mouth may increase the chance of dental disease, including tooth decay, gum disease, and fungus infections.

Contact your doctor as soon as possible if you have chest pain or discomfort, a fast heartbeat, trouble breathing, or fever and chills. These can 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 any of the following symptoms while taking this medicine: 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 any of the following symptoms while using this medicine: convulsions, 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).

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.

Serious side effects of Haldol

Along with its needed effects, haloperidol may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking haloperidol:

Get emergency help immediately if any of the following symptoms of overdose occur while taking haloperidol:

Symptoms of overdose

• difficulty with breathing (severe)
• dizziness (severe)
• drowsiness (severe)
• muscle trembling, jerking, stiffness, or uncontrolled movements (severe)
• unusual tiredness or weakness (severe)

Other side effects of Haldol

Some side effects of haloperidol may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

For healthcare professionals

Applies to haloperidol: compounding powder, injectable solution, intramuscular solution, oral concentrate, oral tablet.

General adverse events

The most common side effects include extrapyramidal disorder, insomnia, and agitation.^[Ref]

Nervous system

• Very common (10% or more): Extrapyramidal disorder (up to 34%), hyperkinesia (up to 13%), headache (up to 12%)
• Common (1% to 10%): Tardive dyskinesia, dystonia, dyskinesia, akathisia, bradykinesia, hypertonia, somnolence, masked facies, tremor, dizziness, parkinsonism/parkinsonian effects
• Uncommon (0.1% to 1%): Convulsion, akinesia, cogwheel rigidity, sedation, involuntary muscle contractions, gait disturbance, persistent tardive dyskinesia
• Rare (0.01% to 0.1%): Motor dysfunction, neuroleptic malignant syndrome, nystagmus
• Frequency not reported: Drowsiness, epileptic/grand mal seizure, vertigo, lethargy
• Postmarketing reports: Opisthotonos^[Ref]

Acute dystonia usually occurred early in treatment.

Sedation may occur more frequently in elderly patients.

Akathisia usually occurred within 6 hours of administration and may be indistinguishable from psychotic agitation.^[Ref]

Psychiatric

• Very common (10% or more): Insomnia (up to 19%), agitation (up to 15%)
• Common (1% to 10%): Depression, psychotic disorder
• Uncommon (0.1% to 1%): Confusion, increased/decreased libido, restlessness, hallucinations
• Frequency not reported: Apparent exacerbation of psychotic symptoms, anxiety, euphoria, agitation, apprehension, toxic psychosis, catatonic-like behavioral states^[Ref]

Gastrointestinal

• Common (1% to 10%): Constipation, dry mouth, salivary hypersecretion/hypersalivation, nausea, vomiting
• Frequency not reported: Dyspepsia, diarrhea, heartburn, excessive salivation^[Ref]

Genitourinary

• Common (1% to 10%): Urinary retention, erectile dysfunction, sexual dysfunction
• Uncommon (0.1% to 1%): Amenorrhea, dysmenorrhea, galactorrhea, breast discomfort/pain
• Rare (0.01% to 0.1%): Menorrhagia, menstrual disorder
• Frequency not reported: Priapism, oligomenorrhea, mastalgia, breast engorgement, lactation^[Ref]

Cardiovascular

• Common (1% to 10%): Orthostatic hypotension, hypotension
• Uncommon (0.1% to 1%): Tachycardia, edema
• Rare (0.01% to 0.1%): QT prolongation (on ECG)
• Frequency not reported: Ventricular fibrillation, Torsade de pointes/polymorphous configuration of Torsade de pointes, ventricular tachycardia, extrasystoles, peripheral edema, venous thromboembolism, deep vein thrombosis, unusual bleeding, heat stroke
• Postmarketing reports: Ventricular arrhythmia, cardiac arrest, hypertension^[Ref]

QT prolongation, Torsade de pointes, ventricular arrhythmias/fibrillation/tachycardia and cardiac arrest occurred more frequently at high doses and/or in patients at risk for cardiovascular side effects.

Tachycardia and hypotension may occur more frequently in elderly patients. Hypotension occurred as a dose-related event.

Heat stroke included hot, dry skin, the inability to sweat, muscle weakness, and/or confusion.^[Ref]

Metabolic

• Common (1% to 10%): Weight increased/decreased
• Frequency not reported: Hypoglycemia, hyperglycemia, loss of appetite, anorexia, hyponatremia
• Postmarketing reports: Hyperammonemia^[Ref]

Hyperammonemia occurred in a pediatric patient with citrullinemia (inherited disorder of ammonia excretion).^[Ref]

Ocular

• Common (1% to 10%): Oculogyric crisis, visual disturbance
• Uncommon (0.1% to 1%): Blurred vision
• Frequency not reported: Cataracts, retinopathy^[Ref]

Dermatologic

• Common (1% to 10%): Rash
• Uncommon (0.1% to 1%): Photosensitivity reaction, urticaria, pruritus, hyperhidrosis
• Frequency not reported: Exfoliative dermatitis, leukocytoclastic vasculitis, Toxic epidermal necrolysis, Stevens-Johnson syndrome, erythema multiforme, maculopapular/acneiform skin reactions, alopecia^[Ref]

Musculoskeletal

• Common (1% to 10%): Muscle rigidity
• Uncommon (0.1% to 1%): Torticollis, muscle spasms, musculoskeletal stiffness
• Rare (0.01% to 0.1%): Trismus, muscle twitching
• Postmarketing reports: Rhabdomyolysis^[Ref]

Other

• Common (1% to 10%): Hyperthermia
• Uncommon (0.1% to 1%): Unusual tiredness/weakness
• Frequency not reported: Neonatal drug withdrawal syndrome, sudden/unexpected death, face edema, hypothermia^[Ref]

Hepatic

• Common (1% to 10%): Abnormal liver function test
• Uncommon (0.1% to 1%): Hepatitis, jaundice
• Frequency not reported: Acute hepatic failure, cholestasis, impaired liver function^[Ref]

Local

• Common (1% to 10%): Injection site reaction
• Frequency not reported: Injection site abscesses, localized erythema/swelling/tender lumps^[Ref]

Respiratory

• Uncommon (0.1% to 1%): Dyspnea
• Rare (0.01% to 0.1%): Bronchospasm
• Frequency not reported: Laryngeal edema, laryngospasm, pulmonary embolism, increased respiratory rate/depth, sore throat, bronchopneumonia/lethal bronchopneumonia^[Ref]

Hematologic

• Uncommon (0.1% to 1%): Leukopenia
• Frequency not reported: Agranulocytosis, neutropenia, pancytopenia, thrombocytopenia, unusual bruising, decreased red blood cell counts, anemia, lymphocytosis, monocytosis, lymphomonocytosis^[Ref]

Agranulocytosis included sore throat/fever and unusual bleeding/bruising, and typically occurred with concurrent use of other drugs.

Leukopenia and leukocytosis were usually mild and transient.^[Ref]

Hypersensitivity

• Uncommon (0.1% to 1%): Hypersensitivity reactions
• Frequency not reported: Anaphylactic reaction^[Ref]

Endocrine

• Rare (0.01% to 0.1%): Hyperprolactinemia
• Frequency not reported: Inappropriate antidiuretic hormone secretion, gynecomastia^[Ref]

Inappropriate antidiuretic hormone secretion occurred with hyponatremia^[Ref]

See also:

Frequently asked questions

• What drugs cause tardive dyskinesia?

Further information

Haldol side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer