Yes, Zero Odor does work in extreme cases of odor.
Zero Odor is effective on all surfaces, such as wood,sheetrock, carpet, tile, etc.
If the odor has become deeply embedded, it's safe to assume that Zero Odor needs an opportunity to become deeply embedded to remove the odor. In other words spray the area heavily. Eventually, Zero Odor will seep in deep enough to become fully effective.
Zero Odor works differently than other odor-removing products. It doesn't contain any enzymes. It works through a chemical-bonding process in which Zero Odor molecules attach themselves to ALL odor molecules, rendering them harmless and odorless. This is a quick and irreversible reaction. Despite its effectiveness, Zero Odor is completely non-allergenic. It's safe for use around people and pets.