Does hydrogen peroxide clear a clogged drain?

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A clogged drain can make the simplest task, like brushing your teeth, an unpleasant mess. If you dislike harsh chemicals as much as you hate waiting for the water in the sink to finally go down, try using hydrogen peroxide to clear a clogged drain instead.

Hydrogen Peroxide

Colourless and only a little thicker than water, hydrogen peroxide is an oxidiser. It damages and destroys organic material including germs, which is why it's used as a disinfectant. It also makes hydrogen peroxide useful for clearing clogged drains. Use 3% strength hydrogen peroxide. This formulation is available in most pharmacies and grocery stores.


To remove a drain clog, pour a cup of baking soda down the stopped up drain. Wait ten minutes, then pour a cup of hydrogen peroxide down the drain. The foaming action of the hydrogen peroxide and baking powder scours away debris inside the pipe, wearing away and loosening the plug. Let them work for a couple hours, then pour hot water down the drain to rinse the clog away. You can use hydrogen peroxide alone to clear the drain, but it will probably require more than one application to work.


If you have a drain that is prone to getting stopped up, hydrogen peroxide can prevent clogs. Every two weeks, pour a cup of hydrogen peroxide down the drain. Wait an hour, then pour a few cups of nearly boiling water into the drain. The hydrogen peroxide will destroy any organic build up in the pipe. It also keeps the drain and pipe free of mould and mildew growth.


Keep hydrogen peroxide in an opaque bottle and store it in a cool cabinet. Exposure to light and heat causes it to break down and lose its effectiveness. Discard any remaining hydrogen peroxide after the expiration date on the bottle. Keep it out of the reach of pets and children. While it is less toxic than harsh commercial pipe openers, it can cause skin irritation and burning in your eyes. If swallowed, it will trigger vomiting and gastric upset.