Carefully pour the solution down the blocked drain. Do not splash it on the porcelain or enamel of your sink/tub, as it can damage the finish.
How to unclog the sink with caustic soda without an accident caustic soda unblock drain
Caustic soda, also known as sodium hydroxide or lye, is a powerful chemical agent commonly used to clear stubborn blockages in pipes. It works by creating an intense exothermic reaction (generating heat) and turning grease, fats, and organic matter into a soap-like substance that can be flushed away. Carefully pour the solution down the blocked drain