Haloperidol-Induced Hyperthermia

Mechanisms and Diagnostic Approach

Haloperidol is among the most frequently reported drugs causing Neuroleptic Malignant Syndrome (NMS) in the ICU setting, particularly among the butyrophenone class of antipsychotics, with a mechanism involving central dopaminergic blockade 1
The lag time between initiating haloperidol and fever development averages 21 days, though it can occur at any point, representing a hypersensitivity reaction where fever develops through dysregulation of hypothalamic temperature control 1
Fever typically resolves 1-3 days after discontinuation but may take up to 7 days 1
Simple drug-induced hyperthermia is characterized by fever without muscle rigidity or significant autonomic dysfunction, with a temporal relationship to haloperidol administration being the primary diagnostic criterion 1
A complete infectious workup is mandatory as infection remains a common cause of fever in hospitalized patients, and the diagnosis of drug-induced fever is established by temporal relationship and exclusion of other causes 1

For suspected NMS, consider benzodiazepines for agitation and muscle activity, and manage hyperthermia with external cooling measures, according to Praxis Medical Insights 2
Treat dehydration and elevated creatine kinase with IV fluids to prevent renal failure from rhabdomyolysis, as recommended by Praxis Medical Insights 2
For simple drug-induced fever, discontinue haloperidol immediately and provide supportive care with antipyretics and hydration, with monitoring for at least 24-48 hours after discontinuation 1, 2

Do not continue haloperidol if drug-induced hyperthermia is suspected—discontinuation is the definitive treatment, as stated by Critical Care Medicine and Praxis Medical Insights 1, 2
Do not assume fever is always infectious in origin when a patient is on haloperidol; consider drug-induced causes early, according to Critical Care Medicine 1
Do not rechallenge patients who experienced NMS with the same antipsychotic, as recurrences have been reported, and do not rechallenge patients who experienced anaphylaxis or toxic epidermal necrolysis with haloperidol 1, 2