Why a 15 kg dog's size offers some buffer
Your medium-sized dog has greater body mass to dilute the toxins compared to smaller pets, but the solanine in tomato leaves remains dangerous in any quantity. The stems and younger leaves contain higher concentrations, so note whether those were part of what was eaten. Even a few chewed leaves can deliver enough solanine to irritate the digestive tract within hours.
Larger dogs often show first signs differently than small breeds - instead of immediate drooling, they may exhibit subtle lip-licking or exaggerated swallowing motions first. Their bigger stomach capacity sometimes delays vomiting, allowing more toxin absorption. Don't wait for visible symptoms before calling for advice given the variable reaction times.
Garden-fresh plant material's unique risks
Freshly picked tomato leaves release more sap containing concentrated solanine compared to dried or wilted plants. The broken stems and torn leaves from your dog's chewing likely exposed them to higher doses than if they'd nibbled fallen debris. Check between their teeth and gums for green plant remnants that could continue leaching toxins.
Outdoor exposures add complication factors like possible pesticide residue or fertilizer contamination on the plants. These can compound the solanine's effects, particularly on the nervous system. If the garden was recently treated with any chemicals, mention this specifically when seeking emergency advice.
Immediate containment strategies
Prevent further grazing by confining your dog away from the garden with close supervision. Even if they seem fine initially, solanine's delayed onset means they might return to nibble more while symptoms are still developing. Offer fresh water to help dilute any absorbed toxins, but don't force drinking if they resist to avoid aspiration risk.
Collect a sample of the exact plant parts consumed - a photo of the damaged plant showing leaf size and stem thickness helps veterinarians estimate dosage. Note whether flowers or unripe tomatoes were also present, as these contain different alkaloid profiles. Time-stamped evidence significantly improves treatment planning if symptoms escalate.
The critical observation checklist
For the next 6 hours, monitor for these progression markers: first excessive yawning or lip-smacking, then audible stomach gurgling, followed by either vomiting or diarrhea. Neurological signs like stumbling or unusual eye movements would indicate severe poisoning requiring IV fluids and medication to control symptoms.
Keep a log with times for each new symptom - this helps veterinarians gauge whether the reaction is accelerating or plateauing. Temperature checks are useful too, as some dogs develop mild fever from the inflammatory response. Any panting unrelated to heat or exercise suggests discomfort needing professional assessment.
The step-by-step response, from the first minute to the vet visit, is in our Tomato & Potato Plants (Solanine) emergency guide.