Blocked drains can be a common enough occurrence, but this doesn't make them any less of an inconvenience. Regular maintenance of your drains is the easiest way to prevent them from becoming blocked, but this not a guarantee that it will never happen. A drain insert can be used in your shower or bath to prevent hairs from entering the drainage system. The same thing can be used in your kitchen sink to prevent food particles from going down the drain. When the drain is blocked, you could just use a harsh chemical unblocker to fix the problem. If you don't like to use such strong, abrasive chemicals, or if you're worried about what the unblocker might do to your pipes, then there are a few natural alternatives you can use.
Fill your electric jug or kettle with water and bring it to the boil. Carefully hold it over the drain and pour a steady stream of water until the jug is empty. Position the spout of the jug close to the drain to minimise the chance of splashback from the hot water. The simple heat of the water is often enough to dislodge organic materials (such as hair or food), which will quickly return the drains to working order. If the blockage is combined with an unpleasant odour (which is the result of the organic materials decomposing), then you might want to add a splash of white vinegar before you pour the water.
While depilatory cream contains a number of fairly potent active ingredients, they are infinitely less harsh than a chemical drain unblocker. Since this method is only effective with drains that are blocked by hair clumps, you should only try it in your bath or shower drain. You will notice that the manufacturer will have listed a maximum time that the cream should be left on your skin. This is because the cream has a corrosive effect on organic material, which is how it weakens your hair's keratin, separating your hair from your body. This corrosive element is what you want. Empty a tube of depilatory cream into the blocked drain and wait for the maximum amount of time listed by the manufacturer. Flush the drain with hot water from your electric jug or kettle. The cream should have partially corroded the hair to the point where it can easily be flushed away.
Baking Soda and Vinegar
All vinegars contain acetic acid, which creates a powerful foaming process when combined with baking soda. While you could technically use any kind of vinegar to achieve the same result, apple cider vinegar and white vinegar perhaps have the most neutral scent (even though the resulting scent can still be quite powerful). Slowly tip one cup of baking soda into the blocked drain. Follow this with the same amount of vinegar. Place the plug into the drain to seal it. If the drain does not have a plug (as is the case in some showers), then simply cover the drain with a wet rag to prevent the foam from moving upwards and to minimise the scent (although you should still ventilate the room as much as possible). The effervescent foam that has been produced by combining the acid (the vinegar) with a base (the baking soda) can be powerful enough to dislodge blockages.
If you have tried these methods to no avail, you will of course need to call a plumber. They will probably use a plumber's snake to dislodge the blockage, so that harsh chemicals still won't be an issue. And once the drain has been unblocked, please consider using a drain insert to stop it from happening again.