Common ivy leaves and berries cause oral irritation, vomiting and diarrhea.
Both indoor English ivy and outdoor climbing ivy are toxic.
Ivy contains triterpenoid saponins (hederagenin) and polyacetylene compounds (falcarinol). Saponins are irritating to mucous membranes and the GI tract; falcarinol can also cause contact dermatitis.
Fontes
Most exposures cause vomiting and oral irritation that resolves with supportive care.