Reptile & Amphibian Practice
Core concepts
Reptiles and amphibians are ectotherms, so environmental temperature determines metabolism, digestion, and immune function. Husbandry is medicine here: temperature gradient, humidity, lighting (UVB for many diurnal reptiles), and enclosure size drive health. Know the major taxa - chelonians, lizards, snakes, crocodilians, and amphibians - because anatomy and common diseases differ. Understand the reptilian renal portal system and the implications for drug administration.
Common presentations
Metabolic bone disease from calcium/UVB deficiency, dysecdysis from humidity problems, respiratory disease, and gastrointestinal obstruction or impaction are high-yield. Anorexia in a reptile is often husbandry-driven. Amphibians have permeable skin and are highly sensitive to water quality and chemicals, including handling residues.
Traps
Questions often test whether you correct the environment before treating with drugs. Another trap is assuming mammalian drug metabolism; reptiles metabolize slowly and dosing intervals are often longer. Also watch for questions that ignore the need for species-specific temperature and humidity ranges.
Worked example
A juvenile bearded dragon presents with soft, bowed limbs and reluctance to move. Metabolic bone disease from inadequate UVB and calcium is the leading diagnosis. The plan corrects lighting and diet and provides calcium, while evaluating for pathologic fracture. Rule of thumb: in reptiles, ask about the enclosure before you ask about the drug - the husbandry history is the physical exam.