From the Guidelines
Anticholinergic toxicity should be treated with supportive care, activated charcoal for recent ingestions, and physostigmine in severe cases, with a focus on stabilizing vital signs and securing the airway, as recommended by the most recent and highest quality study 1. The management of anticholinergic toxicity involves several key steps, including:
- Stabilizing vital signs and securing the airway
- Administering activated charcoal (1 g/kg orally) if the ingestion occurred within 1-2 hours and the airway is protected
- Providing IV fluids as needed
- Using benzodiazepines such as lorazepam 2-4 mg IV or diazepam 5-10 mg IV for severe symptoms like agitation, hyperthermia, or seizures
- Considering physostigmine 0.5-2 mg IV slowly over 5 minutes in cases with significant central anticholinergic effects and after cardiac conduction abnormalities have been ruled out, with repeat doses as needed, as described in the study 1. Anticholinergic toxicity presents with characteristic symptoms, including:
- Hyperthermia
- Pupillary dilation
- Dry mucous membranes
- Flushing
- Delirium These symptoms can be remembered by the phrase "hot as a hare, blind as a bat, dry as a bone, red as a beet, and mad as a hatter" 1. Common causes of anticholinergic toxicity include:
- Antihistamines
- Tricyclic antidepressants
- Antipsychotics
- Plants like jimsonweed Continuous cardiac monitoring is essential as some anticholinergic agents can cause QT prolongation and arrhythmias, highlighting the importance of careful management and monitoring in these cases 1.
From the FDA Drug Label
Physostigmine Salicylate Injection can reverse both central and peripheral anticholinergia. The anticholinergic syndrome has both central and peripheral signs and symptoms. Central toxic effects include anxiety, delirium, disorientation, hallucinations, hyperactivity and seizures. Peripheral toxicity is characterized by tachycardia, hyperpyrexia, mydriasis, vasodilation, urinary retention, diminution of gastrointestinal motility, decrease of secretion in salivary and sweat glands, and loss of secretions in the pharynx, bronchi, and nasal passages Dramatic reversal of the effects of anticholinergic symptoms can be expected in minutes after the intravenous administration of Physostigmine Salicylate Injection, if the diagnosis is correct and the patient has not suffered anoxia or other insult.
Anticholinergic toxicity can be reversed with Physostigmine Salicylate Injection.
- The injection can reverse both central and peripheral anticholinergia.
- Central toxic effects of anticholinergic toxicity include anxiety, delirium, and seizures.
- Peripheral toxicity is characterized by tachycardia, hyperpyrexia, and mydriasis.
- Reversal of anticholinergic symptoms can be expected in minutes after administration of Physostigmine Salicylate Injection 2.
From the Research
Anticholinergic Toxicity
- Anticholinergic toxicity can cause a range of symptoms, including agitation, seizures, hyperthermia, cardiac dysrhythmias, and death 3
- The anticholinergic toxidrome is characterized by both central and peripheral physical findings, including mydriasis, blurred vision, tremors, ataxia, fever, flushed and dry skin, and urinary retention 4
- Central anticholinergic syndrome can be associated with seizures, coma, respiratory failure, and cardiovascular collapse in extreme cases 4
Treatment of Anticholinergic Toxicity
- Physostigmine, a tertiary acetylcholinesterase inhibitor, can be used to assist in the diagnosis and management of severe anticholinergic toxicity associated with an olanzapine overdose 4
- Continuous intravenous infusion of physostigmine can be effective in reversing anticholinergic delirium, but it is rarely used due to concerns about cardiotoxicity and cholinergic excess 5
- Physostigmine has been shown to be effective in decreasing agitation and reversing anticholinergic toxicity in several case studies 5, 6
Diagnosis and Management
- Healthcare professionals should be familiar with common drugs or drug combinations that may induce anticholinergic syndrome, and be able to identify the cluster of signs and symptoms of anticholinergic toxicity 7
- The diagnosis and management of anticholinergic toxicity require a comprehensive approach, including supportive care, cardiac, neurological, and respiratory status monitoring, and the use of physostigmine in severe cases 3, 4
- Simulation-based education can be an effective way to teach healthcare professionals about the diagnosis and management of anticholinergic toxicity 3