Safety verdict
Consulted references classify the plant as toxic or irritating for that pet type.
Pet ingestion lookup
My dog ate Rex Begonia - what should I do?
Begonia rex
Potentially toxic
Contact your veterinarian or an animal poison-control resource now, especially if any amount was chewed or swallowed.
Verified against ASPCA/provenance audit 2026-05-06 on May 6, 2026.
Signs to watch for
Oral irritation, intense burning of the mouth, tongue and lips, excessive drooling, and vomiting.
Escalation note
Ingestion typically results in immediate discomfort due to the presence of calcium oxalate crystals. Please contact your veterinarian if ingestion is suspected.
What to watch for
Heavy drooling, lip-licking, pawing at the mouth, and head-shaking within minutes of biting the plant; vomiting, retching, loss of appetite, and sometimes diarrhea. ASPCA notes that oxalate ingestion can also cause kidney signs in grazing animals — uncommon in dogs but worth flagging to your vet if a large amount was consumed.
Time window
Mouth pain and drooling start within minutes of chewing. Mild ingestions often resolve over a few hours; larger ingestions, especially of the tuber, can keep a dog uncomfortable for the better part of a day.
When to call the vet
Call your vet right away if you see swelling around the mouth or face, difficulty swallowing or breathing, persistent vomiting, or any blood in the vomit. ASPCA Animal Poison Control: (888) 426-4435.
What this means for your dog
Dogs that chew or chomp Rex Begonia get hit fast with intense mouth burning from soluble calcium oxalate crystals — most drop the leaf and start drooling almost immediately. The risk escalates if a dog digs up the plant and eats the tubers, which contain the highest concentration of toxin.
Sources: ASPCA (no first-aid guidance for owners).
Source references
Poison-control resources
This page summarizes source-bound plant-safety information and is not veterinary advice.