Clogged drains are a common household problem.

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You know how it happens. You have guests coming over for dinner in a few hours, and you want everything to be perfect. You take the dirty pots out of the sink and open the strainer, but nothing happens. You search the top of the drain to see if something is blocking the water, but you can't find anything that can easily be removed. You're stuck with a sink full of murky gray water -- the drain is clogged.

There's no good time to lose the use of your kitchen sink or bathroom lavatory without warning, but a stopped-up drain is no reason to panic. Sometimes, simple measures can get things flowing again.

Commercial drain-cleaning products are one option that can be effective in certain circumstances. Some of these products are heavily advertised and their brand names are household words, so you may be tempted to pour them down a clogged drain before trying anything else. However, this may not be the best strategy. In many cases, there are alternatives to drain cleaners that will be more effective and less risky to your health and the environment -- and they may even cost less [source: Harrison].

Read on to learn how to clear clogged drains, how drain cleaners work and how to avoid the dreaded clogged drain.