In zinc toxicosis, dogs most commonly present with which signs?

• A. GI and hematopoietic signs
• B. Dermal signs only
• C. Cardiac signs
• D. Renal signs only

Answer: (A)

The key pattern is that zinc toxicosis in dogs typically causes gastrointestinal irritation and hematologic abnormalities. Ingestion of zinc irritates the GI tract, leading to vomiting, anorexia, abdominal pain, and sometimes diarrhea. As zinc is absorbed, it can cause oxidative damage to red blood cells, resulting in hemolysis and sometimes methemoglobinemia, which produces pale mucous membranes, weakness, and tachycardia. This combination of GI signs with hematopoietic (blood-related) abnormalities is the most characteristic presentation. Dermal, cardiac, or renal signs can occur in some cases but are not the most common pattern.