A little preventive maintenance goes a long way.

Clean drains with baking soda, vinegar and hot water, this can be a great help to freshen and unclog drains. It only takes a moment to prevent major headaches.
Use baking soda that has been used in the refrigerator or freezer to help clean the drains and you'll extend the use of something you otherwise would have just thrown away.

Option #1
Pour 1 cup of baking soda down the drain followed by 1 cup of hot vinegar. Try heating the vinegar in the microwave before adding it to the drain. Wait 5 minutes before flushing the drain with 2 quarts of hot water. You can repeat this process a few times if it is necessary. If this is the first time you have cleaned your drain in a long time it may be necessary to repeat the baking soda flush a couple of times.


Option #2
Try pouring 1 Cup of baking soda and 1/2 Cup of salt down the drain. Let this mixture sit in the drain for several hours, overnight is best, before flushing the drain with 2 cups of boiling water.