Atropine/Belladonna/Datura Poisoning: Causes, Symptoms, and Treatment

1 · Overview

Atropine, hyoscyamine and scopolamine are tropane alkaloids concentrated in plants of the Solanaceae family—most notably Atropa belladonna (deadly nightshade) and Datura stramonium (jimson-weed). These compounds act as potent competitive antagonists at muscarinic acetylcholine receptors, producing the classic “anticholinergic toxidrome.” Untreated, severe poisoning may culminate in seizures, hyperthermia, rhabdomyolysis, dysrhythmia or respiratory failure [1] [2].

2 · Causes & Modes of Exposure

• Accidental ingestion of attractive belladonna berries by children or misidentified wild greens mixed with edible plants [1] [6].
• Recreational consumption of Datura seeds, teas or smoked leaves for their hallucinogenic effect; alkaloid content is unpredictable and easily leads to overdose [1].
• Medication error—excess parenteral or ophthalmic atropine during medical treatment, especially in paediatrics or anaesthesia [1].
• Unregulated herbal products containing belladonna alkaloids in mislabeled doses [1].

3 · Pathophysiology

Tropane alkaloids freely cross the blood-brain barrier and reversibly block M_1-3 receptors in peripheral organs and the CNS. The loss of parasympathetic tone yields:

• Peripheral effects: anhidrosis → hyperthermia; tachycardia; mydriasis; urinary retention; ileus.
• Central effects: agitation, vivid visual hallucinations, disorientation, delirium and, with high doses, seizures or coma [1] [3].

4 · Clinical Features – “Anticholinergic Toxidrome”

Mnemonic	Manifestations
Hot as a hare	Hyperthermia (↓ sweating)
Blind as a bat	Mydriasis, blurred vision, photophobia
Dry as a bone	Dry mouth, dry skin, absent bowel sounds
Red as a beet	Cutaneous flushing
Mad as a hatter	Agitated delirium, hallucinations, picking behaviour

Additional findings: sinus tachycardia, hypertension (or later hypotension), ataxia, urinary retention, decreased lacrimation and cough reflex, possible ventricular dysrhythmias in severe cases [1] [5].

5 · Differential Diagnosis

• Sympathomimetic toxidrome (cocaine, amphetamines) – sweaty patient vs. dry skin.
• Serotonin syndrome – clonus > anticholinergic “dryness”.
• Neuroleptic malignant syndrome – drug history, rigidity.
• Delirium from infection, stroke or metabolic derangement.

6 · Diagnostic Approach

1. Bedside evaluation: history of plant or drug exposure, characteristic vitals, pupillary exam and skin moisture [1] [6].
2. Laboratory: electrolytes, creatine kinase (hyperthermia), creatinine; ECG for QRS/QT prolongation.
3. Toxicology screens rarely detect tropanes rapidly; diagnosis remains clinical [1].

7 · Management & Treatment

7.1 Initial Stabilisation

• Airway / Breathing / Circulation (ABC) – intubate if airway reflexes fail or agitation compromises oxygenation.
• Cardiac monitoring for dysrhythmias; treat wide-complex tachycardia with sodium bicarbonate.
• Active cooling (evaporative, ice packs) if temperature > 38.5 °C.

7.2 Gastrointestinal Decontamination

Activated charcoal 1 g/kg orally/NG if presentation < 1 h post-ingestion and airway protected [6] [8]. Gastric lavage is seldom required.

7.3 Antidotal Therapy – Physostigmine

• Central acting reversible acetylcholinesterase inhibitor; counteracts both peripheral and CNS blockade.
• Adult dose: 1–2 mg IV slow push (0.5 mg/min); paediatric: 0.02 mg/kg (max 0.5 mg) – may repeat every 10–15 min if symptoms recur [5] [6].
• Contra-indications: suspected tricyclic antidepressant overdose (risk of asystole), AV block, severe asthma.

7.4 Symptomatic & Supportive Measures

• Benzodiazepines (diazepam or lorazepam) for agitation or seizures.
• IV fluids for rhabdomyolysis risk, Foley catheter for urinary retention.
• Anti-pyretics ineffective because fever is anticholinergic in origin—focus on external cooling.
• Consider lipid emulsion therapy if refractory cardiovascular collapse (rare case reports).

8 · Prognosis

With prompt recognition and physostigmine therapy, most patients recover within 24–48 h without sequelae. Delay or misdiagnosis may allow complications—heat stroke, aspiration pneumonia, ventricular tachycardia or multi-organ failure—to elevate morbidity and mortality, particularly in children and the elderly [[6]].

9 · Prevention & Public Health Notes

• Educate foragers and gardeners to identify Solanaceae plants accurately.
• Secure ophthalmic or parenteral atropine to prevent accidental paediatric access.
• Regulate over-the-counter herbal products containing belladonna alkaloids.
• School programmes warning adolescents about the dangers of so-called “natural” hallucinogens.

10 · Key Take-Home Points

1. Atropine, hyoscyamine and scopolamine produce a distinct dry, flushed, delirious toxidrome.
2. Diagnosis is clinical; sweat absence plus mydriasis and tachycardia are red flags.
3. Physostigmine is the antidote of choice when serious CNS or cardiac manifestations emerge.
4. Timely supportive care—airway control, cooling, benzodiazepines—prevents fatal complications.
5. Accidental ingestion, especially in children, underscores the need for community education on toxic plants.