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What is Mouse Poison?

When bags of food are gnawed open and droppings litter the kitchen, it often means only one thing: there's a mouse running loose in the house, and it's spreading bacteria and disease. Mice usually infest homes during the colder months as they search for warmth and food. Additionally, mice typically nest inside walls, sometimes making it difficult to trap them using popular mouse snap traps.

Other pest control options include glueboards, live traps, and poison. Mouse poison works well because it plays to what a mouse is searching for: food. There are generally two kinds of mouse poison on the market, with the first being quick-kill or single-dose poisons in the form of either water or food. The second option is slow-acting mouse poison that takes effect after about a week. Both kinds contain poisons including warfarin, diphacinone, pival, chlorophacinone, or fumarin. Most pest-control poison products are dyed green.

The quick-kill or single-dose poisons are generally the most popular because they are effective in a short period of time. When successful, they take anywhere from a couple hours to two days to produce the desired result. Additionally, since they only contain about 2.5 grams of poison (less than 1/100th of an ounce), the amount of poison lying around the house is relatively small. While mouse poison isn't hazardous to humans or family pets in small doses, steps still should be taken to ensure the family and the pets do not ingest it. For example, tamper-proof poisons in boxes can be used. Additionally, the poison should be placed out of reach of pets and children.

Even with single-dose poisons, setting out one box of poison often does not do the trick. The recommended amount of poison can range anywhere from two boxes to well up into the double digits, depending on the size of the infestation and what kind of poison is being used. Each set, or box, of mouse poison also should be placed at least six feet (about 1.8 meters) apart in areas the mice are seen or may be nesting. This will increase the chance that the mice take the bait.

Once rodents feed on the poison, they typically get thirsty as their blood vessels constrict and spasm. Some mouse poison products claim that the mice then attempt to search for water by going outside, but this is not always the case. The mice may return to their nest to die, or, depending on how long until the poison takes effect, they may die in inconvenient places around the house.

In case of the latter, the mouse should always be disposed of immediately. If the mouse dies inside the walls, it will produce a foul odor. The smell will go away on it's own, but to make it a bit more tolerable in the meantime, fragrant, household deodorizer can be used. After a few weeks, the mice should no longer be feeding on the bait, and the poison should be disposed of by throwing it in the garbage.

Written by Elizabeth SanFilippo