Bath fizzies are material products designed to effervesce in personal bath water.

They are also called bath fizzies.

Bath fizzies are infeasible as liquids because of the inability to keep the mixture from reacting prematurely.

In principle a fizzie could release phosphoric anhydride gas, but the release of gas from phosphate salts is so slow that any phosphates present in either beverage or bath fizzies are for other purposes.

The latter can come as small pellets known as bath fizzies or as a bolus known as a bath bomb, and they produce carbon dioxide by reaction of a bicarbonate or carbonate with an organic acid.

Bath fizzies are considered a type of bubble bath product by those using the phrase to refer to baths with bubbles within the water or products for producing such an effect, and should hence be distinguished from foaming products that produce bubbles on top of bath water, also referred to as bubble baths.