Cardiac Glycoside Plant Poisoning Clinical Presentation

As with all toxic exposures, the history should focus on answering the following 6 key questions:

• Who was exposed and are there other victims?

• To what were they exposed?

• When were they exposed?

• Where were they exposed?

• Why were they exposed (unintentional vs intentional)?

• To how much were they exposed (eg, amount, concentration)?

Although acute and chronic plant cardiac glycoside toxicity are treated in similar manners, their noncardiac clinical manifestations differ. In acute toxicity, the following may be present:

• GI symptoms - Usually evolve within minutes to hours, are nonspecific, and include nausea, vomiting, and abdominal pain

• Neurologic symptoms - Often are nonspecific and include weakness and altered mental status (eg, disorientation, confusion, lethargy)

In chronic toxicity, signs and symptoms are insidious, which can make diagnosis difficult. GI symptoms are nonspecific and include the following:

• Anorexia

• Nausea

• Vomiting

• Diarrhea

• Abdominal pain

• Weight loss

Neurologic symptoms include the following:

• Confusion

• Drowsiness

• Disorientation

• Delirium

• Headache

• Hallucinations

• Seizures

Visual disturbances manifest as follows:

• Photophobia

• Blurry vision

• Scotomas

• Decreased visual acuity

• Color vision aberrations (eg, chromatopsia, xanthopsia [ie, yellow halos around lights])

Cardiac symptoms are similar in both acute and chronic toxicity and include the following:

• Palpitations

• Chest pressure or shortness of breath

• Lightheadedness, dizziness, and faintness

In the physical examination, the focus is on cardiovascular, neurologic, and GI systems. On vital signs, bradycardia or tachycardia may be seen. In the absence of concomitant ingestion, environmental exposure, thyroid disorder, or underlying infection, the patient generally is normothermic.

Examination findings for specific systems are as follows:

• Lungs - Examination findings typically are normal in the absence of preexisting disease, but rales have been reported

• Heart - Bradydysrhythmia or tachydysrhythmia can occur, typically with increased automaticity and depressed conduction; pulses may be weak, thready, and irregular

• Abdomen - Abdomen is generally soft; vomiting and diarrhea may be noted; emesis may contain plant material

• Skin - Skin may be pale, diaphoretic, and cool

Neurologic findings are typically nonfocal, and pupillary reflexes are intact. Abnormal findings may include the following:

• Altered level of consciousness

• Hypotonia

• Hyporeflexia

• Dysarthria

• Ataxia

• Horizontal nystagmus

• Generalized seizures