To eliminate the stench from the shower drain  you will only need one more item than necessary: ​​a plastic bottle.

Well yes, a simple plastic bottle that  will help you create a really powerful mixture to eliminate the smell of sewer from your shower.

So grab a big bottle and then get  baking soda and citric acid  . This mixture will help you clean the drains, eliminating the bad smell.

So, dissolve  150 grams of citric acid in a liter of warm water,  pour into the bottle, then take  250 grams of baking soda  and pour it directly into the shower drain.

After doing this, wait a few seconds and then take the bottle and pour its contents down the drain. The combination of the two ingredients will be truly deadly,  they will react with each other and allow the clogged channels to be freed in no time.

To make everything even more effective, you can cover the drain area with a damp cloth, pour a saucepan with very hot water inside, in order to further release all the waste from the drain and completely eradicate the smell.

In addition, citric acid will also help reduce lime residue, another reason for possible bad odors in the drain.