Lead Poisoning in Dogs

In the United States and Canada, lead-based paint remains the primary source of lead poisoning in dogs, notwithstanding its ban in the late 1970s.

The symptoms of lead poisoning are often vague, non-specific, and can be intermittent.

Symptoms of chronic lead poisoning constantly progress over the course of months. Chronic lead poisoning is caused by long-term exposure to relatively small amounts of lead.

Acute lead poisoning causes death within a few days of ingestion. Acute exposure is more likely in puppies and dogs who tend to indulge in dietary indiscretion or who suffer from pica.

With prompt and proper treatment, most animals recover without permanent damage.

Dogs suffering from pica (persistent chewing and consumption of non-nutritional substances) are at greater risk of lead poisoning and other types of toxicity.

Young dogs and puppies are more likely to ingest foreign objects than older dogs and are smaller in size, making them more prone to lead poisoning. Pets living in low-income areas are at a greater risk of lead poisoning.

Lead poisoning can lead to death and, as such, must be treated as an emergency. Megaesophagus has also been reported in cases of lead poisoning in dogs.

Note: If an animal is diagnosed with lead poisoning, the owner should promptly contact the health department as exposure to humans, especially children, is likely.

Lead poisoning is caused by the ingestion of lead-containing objects.

Several objects contain lead:

• Paint: ingestion of lead-based paint is the most common cause of lead poisoning in dogs. Lead-based paints have been banned in the US (since 1978) and Canada (1976), but old buildings are likely to have lead in their paint.
• Lead fishing weights
• Ammunition
• Drapery weights
• Car batteries
• Old toys
• Golf balls
• Improperly glazed ceramic dishes

There is no known history of exposure to lead in up to 90% of cases.

Symptoms of lead poisoning vary depending on dosage and what body system is affected.

The diagnosis is self-evident if ingestion of lead-containing objects or substances is witnessed. A dog showing symptoms associated with lead poisoning generally undergoes the following diagnostics:

• Physical exam
• Urinalysis
• Complete blood count
• Blood chemistry
• Diagnostic imaging is especially useful for identifying metal objects in the digestive tract

Verifying a current rabies vaccination is also important since these two diseases can have a similar presentation.

Early treatment is focused on decontamination. Typical treatment for lead poisoning includes:

• Gastric lavage and enemas
• Endoscopic or surgical removal of the lead source
• Chelation therapy: chelation works as an antidote for lead poisons. Lead binds to the chelation agents allowing it to be eliminated from the animal's system.
• Bathing

Note: there is no safe way to induce vomiting in dogs at home. Induction of vomiting or administration of activated charcoal should always be performed by a veterinarian.

Emergency care for seizures includes:

• Short-acting anticonvulsant drugs
• Fluid therapy

Supportive care may include antiemetics and appetite stimulants.

Monitoring and follow-up are recommended for at least two weeks.

The prognosis for lead poisoning varies greatly; it is influenced by the quantity of lead ingested and the timing of treatment.

If promptly treated, most animals recover within 24-48 hours of treatment.

If treatment is delayed and the animal suffers from prolonged seizures, prognosis is guarded.

Lead poisoning is not contagious. Lead poisoning is entirely preventable with diligent storage and disposal of lead-containing substances.

Incidence in the United States has constantly been decreasing since the 1970s.

• Gastric lavage and enemas
• Bathing
• Endoscopic removal of metal items in the digestive tract
• Chelation therapy
• Anticonvulsant medications for patients having seizures
• Antiemetics
• Appetite stimulants