My small dog chewed a tomato stem — is the risk higher because of her size?

Yes, absolutely. Tomato leaves and stems contain solanine and tomatine, which are toxic to dogs. For a small dog, even a tiny amount relative to her body weight can be enough to cause concerning symptoms like drooling, vomiting, or weakness. This is an urgent situation — do not wait to see if signs develop. Contact your veterinarian or the ASPCA Animal Poison Control Center at 888-426-4435 immediately for guidance specific to your dog's size and what she ate.