Salsa — Food safety facts
Feed with care · Dogs · full breakdown on the linked food page
Onion, garlic and chilli together. All three cause problems.
The full verdict, portion guidance and serving notes are collected on the Salsa food facts page.
Short answer
Yes, salsa is generally more dangerous. Plain tomato sauce is mainly tomatoes, which are safe in small amounts, but salsa almost always contains onion, garlic, and chili peppers. All three of these ingredients are problematic for dogs — onions and garlic can damage red blood cells, and chili peppers can irritate the mouth and stomach. Even a small lick of a strong salsa can cause drooling or an upset stomach, so it's best to avoid letting your dog have any.