You may be able to clear a clogged drain without calling on a plumber. Here are some methods to try, without resorting to possibly dangerous drain-clearing chemicals.
The first step is to make sure that you know where the problem is. If there is more than one drain that is slow, you may have an issue that is outside the home and may require professional action.
You can check your drain covers or strainers. Any solid material, such as hair or kitchen scraps, will be visible and should be easy to remove. A plunger might be needed. Make a gentle start and work up to harder plunging.
You may be able to remove the p-trap, a u-shaped section of pipe under the sink, and clear away a blockage there. Or if that isn’t where the problem lies, you can resort to the snake. You can find a drain auger in home supply stores quite reasonably priced. You run the snake down the drain and turn the handle. If your drain doesn’t respond to these steps, the clog may be beyond your reach.
A home-owner’s attempt to clear a blocked toilet usually starts with a plunger. The toilet plunger has a collar on it, not like sink plunger with its flat surface. After plunging comes the snake or drain auger. The toilet auger will have some sort of covering to keep the metal from scratching and damaging the porcelain of the toilet.
After these attempts, if you haven’t found the solution to your problem, you will probably want to call in a qualified professional to deal with your clogged drain.