Snail bait toxicity in pets

The exact toxic mechanism of metaldehyde is unclear. It may convert to acetaldehyde after ingestion, although studies in rats have not confirmed this. Recent evidence suggests metaldehyde may increase excitatory neurotransmitters or decrease inhibitory ones, lowering the seizure threshold. In experimental mice, decreased GABA, NE, and 5-HT levels were observed, along with increased MAO levels. Metabolic acidosis and hyperthermia may also contribute to its toxic effects.

Onset: Symptoms may appear immediately or up to 3 hours after ingestion.

Early Signs: Anxiety and panting.

Neurological Symptoms: Muscle tremors, progressing to intermittent or continuous seizures not necessarily triggered by stimuli.

Hyperthermia: Body temperature may reach 108°F (42.2°C) due to excessive muscle activity, potentially causing DIC or multiple organ failure.

Cardiovascular and Respiratory: Tachycardia and rapid breathing (hyperpnea) between convulsions; heightened sensitivity to sound, light, and touch.

Ocular Symptoms: Possible nystagmus (eye movement) or dilated pupils (mydriasis).

Gastrointestinal Symptoms: Hypersalivation, vomiting, and diarrhea.

Motor Symptoms: Ataxia, especially before or between seizures.

Emesis (within 2 hours after ingestion):

• Avoid emetics if the pet is seizing, comatose, or overly sensitive to stimuli.

Gastric Lavage (if emesis is ineffective or patient is symptomatic):

• Perform gastric lavage with water (3–5 mL/kg) until fluid is clear.

• Follow with activated charcoal (1–3 g/kg) and a sorbitol cathartic (4 g/kg PO).

Symptomatic Treatment:

• Control symptoms (e.g., muscle relaxants, anticonvulsants, cooling measures) before attempting gastric lavage under anesthesia. Protect the airway during this process.

Inpatient Intensive Care:

• Continue treatment until convulsions and hyperthermia are managed.

• Treat metabolic acidosis based on blood gas results, with sodium bicarbonate (0.5–1 mEq/kg IV over 1–3 hours) for severe acidosis.

Hyperthermia Management:

• Use cool water baths, ice packs, and IV fluids to lower temperature to 103.5°F, then discontinue cooling.

Additional Support:

• Use antiemetics or prokinetics to prevent aspiration.

• IV fluids may help with cooling, dehydration, electrolyte balance, and acidosis.

Seizure Control (No Antidote Available):

• Use diazepam (0.5–1 mg/kg IV), repeating in 5 minutes if needed.

• Phenobarbital (4–16 mg/kg IV) or pentobarbital (3–15 mg/kg IV) can be used if seizures persist.

• Methocarbamol (50–150 mg/kg IV, max 330 mg/kg/day) can control muscle tremors.

An urgent veterinary visit is essential for pets exposed to metaldehyde. Prognosis depends on the amount ingested, the speed of treatment, and the quality of care provided. Delayed or insufficient treatment can lead to death within hours of exposure.