Haloperidol

Intramuscular
Psychoses, Schizophrenia

Oral
Severe tics, Tourette's syndrome

Oral
Mania, Psychoses, Schizophrenia

May be taken with or without food. May be taken w/ meals to minimise GI irritation.

Severe toxic CNS depression, comatose states, Parkinson’s disease, basal ganglia lesions, thyrotoxicosis, significant cardiac disorders (e.g. acute MI, uncompensated heart failure, arrhythmias, clinically significant bradycardia, 2nd or 3rd degree heart block, uncorrected hypokalaemia). Lactation.

Patient with dementia-related psychosis, bipolar disorders, seizures or EEG abnormalities, risk of falls, risk of QT prolongation, risk factors for stroke, severe CV disease, decreased gastrointestinal motility, paralytic ileus, urinary retention, BPH, xerostomia, visual problems, and narrow angle glaucoma. Concomitant use with antidepressants and anticholinergic agents. Avoid abrupt withdrawal. Renal and hepatic impairment. Elderly. Children. Pregnancy.

Significant: Extrapyramidal syndrome (e.g. pseudoparkinsonism, akathisia, tardive dyskinesia, dystonia), CNS depression, anticholinergic effects (e.g. constipation, xerostomia, blurred vision, urinary retention), esophageal dysmotility and aspiration, somnolence, orthostatic hypotension, motor or sensory instability, hyperprolactinaemia.
Cardiac disorders: Cardiac arrhythmia, tachycardia.
Eye disorders: Visual disturbance.
Gastrointestinal disorders: Diarrhoea, nausea, sialorrhoea, vomiting.
General disorders and administration site conditions: Injection site reaction.
Hepatobiliary disorders: Jaundice.
Metabolism and nutrition disorders: Anorexia, hypoglycaemia.
Nervous system disorders: Agitation, restlessness, headache.
Psychiatric disorders: Confusion, depression, insomnia.
Renal and urinary disorders: Urinary retention.
Reproductive system and breast disorders: Erectile dysfunction, gynaecomastia, priapism.
Respiratory, thoracic and mediastinal disorders: Bronchospasm, dyspnoea.
Skin and subcutaneous tissue disorders: Acneiform rash, maculopapular rash.
Vascular disorders: Hypotension.
Potentially Fatal: Neuroleptic malignant syndrome, bronchopneumonia, blood dyscrasias (e.g. leucopenia, neutropenia, agranulocytosis), QT prolongation, torsade de pointes.

IM/IV/Parenteral/PO/SC: C

This drug may cause somnolence, if affected, do not drive or operate machinery. Avoid exposure to extreme heat. Avoid strenuous exercise. Ensure adequate fluid intake to prevent dehydration.

Monitor mental status, CBC, electrolytes balance, ECG, liver function, serum glucose and HbA_1c level, hemorrhage, abnormal involuntary movements or parkinsonian signs, visual changes.

Symptoms: Severe extrapyramidal reactions, hypotension, and sedation. Sometimes coma with respiratory depression and hypotension which could be severe enough to produce shock-like state. Management: Symptomatic and supportive treatment. Empty stomach by inducing emesis or gastric lavage after an acute ingestion. Administer activated charcoal to decrease drug absorption. Use mechanically assisted ventilation (e.g. oropharyngeal airway, endotracheal tube) to establish and maintain a patent airway during respiratory depression or coma. Treat convulsion with diazepam and monitor respiratory status. Hypotension and circulatory collapse may be treated by IV fluids, plasma or concentrated albumin and vasopressor agents (e.g. dopamine, noradrenaline). Administer benztropine mesylate 1-2 mg (IV or IM) in severe cases of extrapyramidal reactions. Treat severe arrythmia with appropriate anti-arrhythmic measures. Monitor ECG and manage hypothermia.

Altered concentration of haloperidol with CYP3A4 and CYP2D6 inhibitors and inducers. May increase plasma concentration of tricyclic antidepressant.

Description:
Mechanism of Action: Haloperidol is a butyrophenone. It nonselectively inhibits postsynaptic dopaminergic D₂ receptors in the brain.
Pharmacokinetics:
Absorption: Readily absorbed from the gastrointestinal tract. Bioavailability: Approx 60-70% (oral). Time to peak plasma concentration: 2-6 hours (oral); 20 minutes (IM).
Distribution: Crosses the blood-brain barrier; enters breast milk. Plasma protein binding: Approx 92%.
Metabolism: Extensively metabolised in the liver via oxidative dealkylation and ultimately conjugated with glycine.
Excretion: Via urine (30%, 1% as unchanged drug). Elimination half-life: Approx 12-38 hours (oral).

Source: National Center for Biotechnology Information. PubChem Database. Haloperidol, CID=3559, https://pubchem.ncbi.nlm.nih.gov/compound/Haloperidol (accessed on Jan. 23, 2020)

Oral: Store between 20-25°C. Solution for injection: Store between 20-25°C. Do not refrigerate or freeze. Protect from light.

Antipsychotics / Antivertigo Drugs

N05AD01 - haloperidol ; Belongs to the class of butyrophenone derivatives antipsychotics.

Anon. Haloperidol. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 08/06/2017.

Buckingham R (ed). Haloperidol. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 08/06/2017.

Haldol Injection (Janssen Pharmaceuticals, Inc). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 08/06/2017.

Joint Formulary Committee. Haloperidol. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 08/06/2017.

McEvoy GK, Snow EK, Miller J et al (eds). Haloperidol, Haloperidol Decanoate, Haloperidol Lactate. AHFS Drug Information (AHFS DI) [online]. American Society of Health-System Pharmacists (ASHP). https://www.medicinescomplete.com. Accessed 08/06/2017.