How to fix a stinky shower drain?

Pour a cup of bleach in the drain before you shower for a few days. If this hasn't happened before it may not be the venting. Probably a little bacteria conspiracy that needs a little genocide action.

buy some buttermilk & pour it down the drain before you go to bed. the enzymes in the buttermilk eat up all the smelly bacteria & sweetens the pipe right up. It works--have done it.

Clean it out. Make sure it has a trap that is holding water.

It's sewer gas coming back up the drain. All fixtures that drain into the sewer system are designed to prevent sewer gas from entering the house by some means. Usually its an s curve in the drain pipe such that water remains in the curve and blocks gas from reaching the inside of the house. Part of making that system work is having each fixture close enough to a roof vent to prevent the system from developing suction that will pull the water out of the traps. If you smell sewer gas (weird smell in your drain) this means that either your vent is plugged, or there is no water in the trap under the shower. If you seldom use the shower, the water can evaporate out of the trap and leave a clear path for the sewer gas to come up into the bathroom. The solution can be as simple as running the water in the shower once in a while if you don't use it every day. Assuming that is not the case, either your shower was installed without a trap under the drain, or the vent system is not working correctly and too much suction is pulling the water out of the trap. If you can see under your shower, perhaps by going into your basement, look to confirm that a trap is installed under the drain. If you see one, then focus on the vent system. Go up on your roof if its safe to do so, and inspect the vent pipes to be sure they are not blocked or plugged. If they look clear, then the problem is more subtle. If all looks good, check around the house to see if other fixtures smell too, or if the toilets occasionally have the water pulled out of the bowl without anyone flushing. this is a sign of excess suction in your system. At this point it may be wise to consult a licensed professional to diagnose. I have this condition in my home occasionally, and all I need to do to prevent the smell is make sure I close the drain on my whirlpool tub and slide a flat rubber stopper over the shower drain in the upstairs bathroom after each shower. Its the only bathroom that has the problem, and these measures have been easier than correcting the venting problem and are very little trouble. Good luck!

Drano half bottle, than let sit for 30-45 min, then run or pour hot H20 for a few mins. Now another thing home remedy pour baking soda then pour vinegar, let sit for 30 mins then run hot H20 for a few mins.

Stinky smells from plumbing are always something to worry about, not a "how do I stop the smell" worry, but a "deadly gas entering my house" worry. There are many causes for a smelly shower drain, the most common being that it is not vented properly, and the p-trap is being siphoned dry allowing methane gas to enter your home. Usually it is not just because there is a build up of stinky stuff in it, there should be standing water in the p-trap that prevent any smells from coming out. I could sit here and write you a book on how to figure out whether or not your shower actually has a p-trap and weather it it vented right, but I only type with two fingers. Hope this helps, and good luck.

Pull the dead ferret out of the hole.