Flushing Medications Harms Your Septic System

Many houses in more rural settings are too far away from typical sewer lines to be connected to a bigger network. Due to distance, these homes have to use septic tanks. If you’re reading this article about septic tanks, chances are you have one. It is important to know everything you can about flushing medications and other unwanted items down into your septic tank.

As you may or may not know, a septic system ends with a big tank. This tank that is buried in your yard somewhere, and of course it can be different sizes. A well-designed tank will be large enough that you should only need to pump your tank every three years or so. Water will flow into the tank from one end and leave from the other.


A septic tank has its own bacterial environment complete with all kinds of gases. These gases are the result of bacteria breaking down any organic material which flows into the septic tank. So, a septic tank is actually something of a living entity.

Heavier waste will sink to the bottom of your septic tank after it flows in. The liquid waste will flow through your septic tank’s exit pipe. From the exit pipe, liquid waste goes out into a drainfield. The drainfield is usually comprised of a series of pipes that spread out the liquid waste. That liquid waste exits the drain pipe, usually into some sort of rock or gravel clearing.

Many people like to use their toilets to get rid of unwanted items such as goldfish, organic waste, and even medication. There are many obvious problems with using your toilet as a disposal system. One, of course, is that objects like goldfish, tampons, etc., can clog up your septic tank fairly quickly, causing it to back up or overflow.


Another negative side effect, specifically of flushing medications, is that medications can harm the environment, killing plant and animal life. In addition, chances are that that your septic tank is near a water source. Medications contaminate liquid waste, seeping into the ground and potentially contaminating that nearby water source.

Typical over-the-counter medications will not cause too much of an issue. However, you need to watch out are “antibiotics and certain strong medications, such as those used in chemotherapy [because they] can affect the operation of your system.” This is because the chemicals in your medications can affect the growth of the bacteria we mentioned earlier. That bacteria, as stated previously, breaks down your organic waste very efficiently and helps to slow the accumulation of what is known in septic tanks as the “sludge layer” – the remains of the solid waste which your body produces.

To keep your septic system healthy, make sure you properly dispose of your medications. There are always places within your community that offer to take in unused medication to be properly disposed of. If you cannot reach your community medication program, you can crush up your medicine and place it with some undesirable substance, usually kitty litter, in a sealable plastic baggie. This will help to prevent animals from thinking it is edible and trying to consume whatever is in your trash. Then you can simply throw out that plastic bag with your regular garbage.


  • I appreciate the information you shared on why you shouldn’t be flushing medications into septic systems. I am definitely guilty of flushing medicine down my toilet. It might be a good idea for me to contact a septic cleaning service and have them pump my tank out.
    - Dennis Sanchez
  • Post more! Seriously, I am really digging what you have written so far. I’ve scanning your blog right now for more things to read.
    - Jay
  • Wow, I had no idea that flushing meds had that effect on a system, though I suppose that interfering with the bacterial growth in the system would cause some problems, like antibiotics do to my stomach. My husband and I have been flushing some of our pain medications after recovering from some recent surgical procedures, and though we did break it up and try to dilute the pills somewhat, it still could potentially harm the environment and cause problems for the wildlife, as you said. We’ll be sure to stop doing that and get our septic system cleaned out so that we don’t have any residual effects lingering from our previous poor habits.
    - Rhianna Hawk
  • It’s so true that many people tend to flush unwanted items in the toilet. This would explain the cause of the septic problems she’s starting to deal with. She treats her toilets like a garbage disposal.
    - Becca Holton
  • Thanks for bringing to my attention that medications can affect the bacterial growth in your septic tank. I hadn’t considered that flushing medications could be a damaging method of disposal. With that in mind, I’ll definitely stop doing that in the future, and maybe it would be a good idea to have a professional come and check our tank to make sure it’s still functioning properly and has the right bacteria.
    - Lillian Schaeffer
  • I want to make sure that I take care of my septic tank. I didn’t realize it was so important to be careful what you flush down the drain! I’ve flushed medication down the drain before, so I might have to see if I can get a professional to check to make sure that my drain makes sense.
    - Braden Bills
  • I had no idea that septic systems have their own gasses and chemicals. I just thought they were a container for waste. My wife flushed her old antibiotics down the sink the other day. I hope it didn’t screw up my septic system. I’ll have to call someone to come check it for me.
    - Kody Loveless
  • I own a house with a septic tank and want to take good care of him. Thanks for the advice about how flushing medication can harm the environment by seeping into the ground. It would also be good to get your septic tank inspected by a professional once a year.
    - Sarah Smith
  • My grandmother disposes of her old medications my flushing them down the toilet. So, I like that you pointed out that isn’t a good thing to do because it causes damage to your tank. It seems that I should take her expired medication take them to a disposal place.
    - emily bennette
  • I had no idea that flushing medications could harm my septic system! I’m SO glad I found this post. I usually get rid of old/expired medications by flushing them, so I’ll make sure to stop doing that. Do you think I should look into getting my septic tank professionally cleaned in order to reverse the damage I’ve done?
    - Megan Earl
  • Medications are not the only thing your find in septic tanks. People will call a cesspool service for whatever problem they are having. After conducting a video inspection, You will find tampons, condoms, toys, animal bones, etc.
    - Bob Baker

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