Lye is a strong alkaline solution made from sodium or potassium hydroxide. It is used in soapmaking and for cleaning and opening drains. If your toilet becomes clogged, sprinkling a small amount of lye in the toilet will help unclog it. Before using lye, carefully read the manufacturer's instructions for use of the product.

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Lye is used to clean and unclog drains, including those in toilets.

Step 1

Place a plunger in the toilet. Push down on the toilet to try to unplug or unclog the toilet.

Step 2

Add the appropriate amount of lye into the toilet, following the manufacturer's directions. Wait the amount of time recommended by the manufacturer.

Step 3

Flush the toilet. If the toilet flushes normally, the drain is cleared. If the toilet does not drain, or is slow draining, repeat Step 2. Never plunge or snake a drain once chemicals have been added.