Does Baking Soda Kill Mice? No — Here's Why
No. Baking soda does not reliably kill mice and won't resolve an infestation. The method is not registered with the EPA as a rodent control agent and has no peer-reviewed efficacy data.1
The Theory
The claim: baking soda reacts with stomach acid to produce CO₂ gas; mice can't release gas the way humans can, so pressure builds until they die. Some versions of this add peanut butter, sugar, or cocoa powder to the baking soda to get mice to eat it.
The chemistry is real — sodium bicarbonate does produce CO₂ when it meets acid. The problem is everything that comes after.
Why It Fails in Practice
Mice don't eat enough of it. A lethal dose requires the mouse to consume a significant amount of baking soda. Mice are neophobic — cautious around new food sources — and nibble small amounts before committing. They rarely consume enough of any novel mixture to reach a lethal dose.
Mice have alternatives. If any normal food is available, they'll eat that instead of your baking soda bait. In a home with crumbs, pet food, or any unsealed pantry items, mice aren't going hungry enough to rely on your mixture.
The gas doesn't necessarily build up fatally. Mice can expel gas through means other than burping. The idea that pressure inevitably accumulates to a lethal level isn't supported by evidence.
The method isn't EPA-registered for rodent control and has no peer-reviewed efficacy data. Pest control professionals don't use it.
One Caution If You Try It Anyway
Some homemade recipes suggest mixing baking soda with artificial sweetener. If you have dogs, be careful — xylitol (found in many sugar-free sweeteners) is highly toxic to dogs. Don't leave any bait mixture where pets can reach it.
What Actually Works
Snap traps set correctly are faster, cheaper, and reliably effective. Baking soda takes days of uncertain exposure; a snap trap works in seconds.
How to kill mice — methods that work →
Trap recommendations and placement →
How to get rid of mice (full guide) →
Sources
- U.S. Environmental Protection Agency. "Rodenticides." epa.gov/rodenticides — Registered rodenticide active ingredients; sodium bicarbonate is not listed as a registered rodent control agent.