Haloperidol Side Effects
Some side effects of haloperidol may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.
For the Consumer
Applies to haloperidol: oral tablet
Get emergency medical help if you have any of these signs of an allergic reaction while taking haloperidol: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have a serious side effect such as:
dizziness, fainting, fast or pounding heartbeat;
restless muscle movements in your eyes, tongue, jaw, or neck;
tremor (uncontrolled shaking);
pale skin, easy bruising or bleeding, flu symptoms;
very stiff (rigid) muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, feeling like you might pass out;
stabbing chest pain, feeling short of breath, cough with yellow or green mucus;
sudden mood changes, agitation, hallucinations, unusual thoughts or behavior; or
jaundice (yellowing of your skin or eyes).
Less serious side effects of haloperidol may include:
headache, dizziness, spinning sensation, drowsiness;
sleep problems (insomnia);
feeling restless or anxious;
mild skin rash or itching;
breast enlargement, irregular menstrual periods, loss of interest in sex; or
dry mouth, blurred vision, urinating less than usual.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.
For Healthcare Professionals
Applies to haloperidol: compounding powder, injectable solution, intramuscular solution, oral concentrate, oral tablet
Local side effects have included noninfectious, edematous, pruritic, tender masses after intramuscular injection of haloperidol decanoate. These resolved slowly over months.
The drowsiness associated with haloperidol therapy may resolve after several doses.
Tardive dyskinesia involves involuntary, dyskinetic, repetitive movements and may be more common in elderly women receiving haloperidol. Tardive dyskinesia may be irreversible and is related to both the duration of therapy and the total amount of drug consumed. Frequent discontinuation and resumption of therapy may predispose patients to the development of tardive dyskinesia.
A study of 19 Veteran Administration hospital patients receiving haloperidol decanoate has reported a prevalence rate for tardive dyskinesia of 42%.
Dystonias frequently involve tongue protrusions, muscle rigidity, torticollis, and opisthotonos. Dystonias usually resolve after neuroleptic discontinuation, but may require antihistamine and antiparkinsonian therapy if symptoms are severe or if respiration is compromised. Treatment of dystonic reactions and extrapyramidal effects, in addition to general supportive measures, may include judicious use of one or more of the following: benztropine, trihexyphenidyl, biperiden or diphenhydramine.
Pseudo-parkinsonism involves flat facies, pill-rolling tremor, shuffling gait, and cogwheel rigidity. Pseudo-parkinsonian symptoms may respond to judicious use of one or more of the following: benztropine, trihexyphenidyl, biperiden or diphenhydramine.
Fever, altered consciousness, autonomic dysfunction and muscle rigidity are the hallmarks of the neuroleptic malignant syndrome. The neuroleptic malignant syndrome is associated with a case fatality rate of about 20%. Immediate discontinuation of neuroleptic therapy, consideration of dantrolene administration as well as intensive monitoring and supportive care are indicated.
Seizures associated with haloperidol have been reported, but many of the reports involved patients with a history of seizures or underlying organic brain disease.
Lower (worse) baseline scores predicted greater cognitive improvement. Change In cognitive performance was weakly related to change in symptom scores.
Nervous system side effects are common and have included sedation, drowsiness, and rarely seizures. Tardive dyskinesia, dystonia, pseudo-parkinsonism, increased neuromuscular excitability, and the neuroleptic malignant syndrome (NMS) have also been reported. Low doses of haloperidol have been associated with improvement on cognitive test performance in patients in the early stages of schizophrenia.
Other side effects including the anticholinergic effects constipation, dry mouth, urinary retention, and blurred vision have been reported.
Baseline and periodic monitoring of liver function tests during haloperidol therapy is recommended for patients with liver disease.
Hepatic side effects including transient elevations in liver function tests have been reported.
Cardiovascular side effects including hypotension, hypertension, tachycardia, and cardiac arrest associated with haloperidol therapy have been reported rarely (although many of these patients have had serious underlying diseases). A number of cases of prolonged QT interval and torsades de pointes have been reported in patients treated with parenteral haloperidol. Sudden death and unexpected death have also been associated with haloperidol administration.
Most of the cases of prolonged QT interval and torsades de pointes have involved patients treated for intensive care unit delirium. Cardiac monitoring is recommended for intensive care unit patients who must receive haloperidol for delirium.
Endocrinologic side effects including hyperprolactinemia and galactorrhea have been reported. Haloperidol-induced hyperprolactinemia has been associated with sexual dysfunction in some male patients.
One in vitro study has suggested that haloperidol may increase sperm motility.
According to one report involving patients on long-term haloperidol use (mean dose 15.7 mg/day; mean duration of illness 15.5 years), the mean prolactin level and the prevalence of chronic hyperprolactinemia were significantly higher in women than in men (74 vs 24 ng/mL and 93% vs 47%, respectively).
Respiratory side effects including bronchospasm and pneumonitis have been reported rarely.
Hematologic side effects including reversible leukopenia and leukocytosis have been reported.
Musculoskeletal side effects including two cases of rhabdomyolysis (without evidence of overt NMS) have been reported. A case of laryngeal dystonia secondary to haloperidol has also been reported.
Genitourinary side effects including priapism have been reported.
More haloperidol resources
- haloperidol Advanced Consumer (Micromedex) - Includes Dosage Information
- haloperidol Concise Consumer Information (Cerner Multum)
- haloperidol MedFacts Consumer Leaflet (Wolters Kluwer)
- Haloperidol Professional Patient Advice (Wolters Kluwer)
- Haloperidol Prescribing Information (FDA)
- Haloperidol Monograph (AHFS DI)
- Haldol Prescribing Information (FDA)
- Haldol Decanoate Advanced Consumer (Micromedex) - Includes Dosage Information
- Haldol Decanoate Prescribing Information (FDA)
- Haldol Decanoate MedFacts Consumer Leaflet (Wolters Kluwer)
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