Foods That Should Never Be Offered
The list of foods that can seriously harm or kill a reptile is shorter than most keepers think — but the consequences of getting it wrong can be fatal. Many reptile poisonings happen accidentally: a fallen avocado in the enclosure, a piece of onion in a salad mix, a houseplant the animal grazed on while free-roaming. This page catalogs every food we've documented as toxic to reptiles, ranked by severity and with notes on why each one is dangerous.
Fatal items like avocado (contains persin, a fungicidal toxin), onion and garlic (cause hemolytic anemia by breaking down red blood cells), and rhubarb leaves (extremely high oxalic acid concentrations) should never come into contact with your reptile under any circumstances. High-toxicity items like raw potatoes (contain solanine), uncooked beans (contain lectins), and chocolate (theobromine toxicity) can cause severe illness even in small quantities.
Some foods are species-specific hazards rather than universal toxins. Iceberg lettuce, while not chemically toxic, has no nutritional value and causes diarrhea in herbivores. Spinach and beet greens bind calcium in plant-eating species and contribute to metabolic bone disease over time. Fatty insects like waxworms can cause hepatic lipidosis in lean species like leopard geckos. Each entry below notes which species are most affected.
If your reptile has ingested any food on this list, contact an exotic-animal veterinarian immediately. Early intervention dramatically improves outcomes. The Association of Reptilian and Amphibian Veterinarians maintains a vet locator at members.arav.org/search.