It's a fact of life that sinks get clogged with food buildup, toothpaste or other debris. When that material won't wash down the drain, it's time to use something that can break up the clog without damaging your plumbing system. Some common household items can safely clear a clogged pipe.
Place a plunger over the sink drain and plunge it for about 10 seconds, just as you would plunge a toilet. You may need a small plunger if your sink is rounded and the plunger does not fit tightly enough over the drain to create suction.
Turn on the hot water and run about 2 quarts of water down the drain.
Pour 1/2 cup baking soda along with 1/2 cup white vinegar into the drain if the sink continues to drain slowly. Let the mixture sit for one hour.
Turn on the hot water and run about 2 quarts down the drain again to rinse away the loosened buildup.