The following Drano products are safe to use in your home's garbage disposal: Drano Max Gel Clog Remover, Drano Dual Force Foam, Drano Pipe & Septic Care and Drano Liquid Clog Remover. Drano Kitchen Crystals Clog Remover is not safe or recommended for use in your home's garbage disposal, according to SC Johnson. Drano Kitchen Crystals Clog Remover is a granular form of Drano that will clump inside of your garbage disposal once it is mixed with hot water, resulting in a clogged disposal.
Open the bottle of Drano by pushing down on the cap with the palm of your hand, turning the cap counterclockwise. Pour half of the 32 oz. bottle of drain cleaner slowly down your garbage disposal's opening for slow-running drains. If the drain/disposal is completely clogged, pour the bottle's entire contents down the disposal's opening. Allow the chemical to break down the debris for 15 to 30 minutes. Turn on your sink's hot water valve and let the water push the debris and chemical from the drain. Turn on your garbage disposal only if the water is flowing smoothly down the drain.
If you see the hot water backing up in the drain, do not turn on the disposal. This will cause the Drano to splash back into your face. Repeat the steps in the "Using Drano" section to break up the remaining debris. If the drainage problem is still present after three or four attempts at clearing it, consult a plumber to check the disposal and drain pipe.
Use Drano again as directed after one month as a follow-up treatment for your kitchen's garage disposal, sink and drain. Using the chemical monthly helps to keep the disposal and drain debris free and flowing smoothly.