If you flush the wrong things down the toilet you can really mess up your plumbing. Homeowners like you need to know top 5 things you should never flush down the toilet. Not only can a clogged toilet or drain cause costly repairs, but it can also harm the sewer system, septic system, and the environment. In this blog you will learn exactly what not to flush, why, and what actually belongs in the toilet.
1. Baby Wipes (Even “Flushable” Wipes)
You might think baby wipes, wet wipes, or anything labeled flushable wipes are safe to flush. That is not true. These wipes do not break down like toilet paper does. Instead, they clog pipes, block the sewer system, cause a clogged toilet, and can lead to messy, costly repairs. As Portland’s official waste services warn, wipes clog pipes—even ones marketed as flushable—because they pile up and create a blockage over time.
2. Paper Towels, Tissues, Cotton Balls
Paper towels, facial tissues, and cotton balls may seem harmless since they are paper. But they are designed to absorb water, not dissolve it. That makes them prime candidates for clogging your plumbing, drain, or even harming your septic tanks and sewer system. Better Homes & Gardens points out these non‑flushable items do not disintegrate and often cause plumbing issues or a clogged drain.
3. Feminine Products, Diapers, Cat Litter, Cigarette Butts
Any maxi pads, tampons, diapers, or kitty litter (also called cat litter) should go straight to the trash. These items absorb water, swell, and lodge in the pipes and septic system. Even some kitty litter brands claim they are flushable, but they still cause blockage and damage to septic tanks and the sewer system.
Likewise, cigarette butts are toxic and clog toilets. Pets or wildlife may be harmed if they enter the wastewater stream; the chemicals can even lead to environmental damage.
4. Household Chemicals, Grease, Paint, Medications, Hazardous Waste
Never flush household chemicals like cleaning products, paint, oil, grease, or other hazardous waste. Grease or cooking fat will solidify and create stubborn blockages in your pipes and sewer lines, even forming massive fatbergs.
Medications are trickier. The FDA’s flush list identifies certain dangerous drugs that can be lethal in one dose, such as some opioids and stimulants. In very special cases—if a drug take-back option is not available and the medication is on the flush list—you may flush it. But that is rare. If it is not on that list, you should dispose of it in the trash by mixing with cat litter or coffee grounds, sealing it, and scratching out your personal information.
Flushing medications not on that list can harm septic tanks, pollute waterways, cause environmental damage, and result in costly plumbing issues.
5. Hair, Dental Floss
Hair and dental floss might be small, but they are powerful cloggers. Hair forms a tangled net that catches debris and builds up over time, creating a major blockage. Dental floss is especially sneaky because it wraps around items and can tangle up the entire sewer system.
Both types of non‑flushable items are guaranteed to lead to sewage backups, plumbing issues, and even environmental damage if not treated properly.
What You Can Safely Flush
There are only three things you should flush:
- Human waste (poop or pee)
- Toilet paper (only the kind designed to break down quickly in toilet water)
That is it. Anything else is dangerous for your plumbing, septic tank, or city sewer system.
Why It Matters
Flushing the wrong stuff is not just a home problem—it is a real threat to our environment. Items like non‑flushable items, household chemicals, or meds can pass untreated through wastewater treatment and end up in rivers, waterways, or harm fish and wildlife.
Plus, clearing a clogged drain or toilet can cost hundreds, or even thousands of dollars. The average costly repairs for removing a fatberg or clog can be overwhelming.
Wrapping Things Up
To keep your bathroom and sewer system safe, remember the top 5 things you should never flush down the toilet: baby wipes or any flushable wipes, paper towels or tissues, feminine products or cat litter, grease or hazardous household waste, hair and dental floss. When in doubt, think trash, not toilet.
Share this with your kids, roommates, or anyone who flushes without thinking. Want professional help or tips? Chambliss Plumbing Company has been serving the San Antonio community for over 30 years, and are ready to help with your residential plumbing needs.
FAQs
Can a single flush of wipes really clog my pipes?
Yes. Even one wet wipe can catch on a joint in your pipes and start building a blockage that becomes a major clog.
What if food or grease accidentally goes down the toilet?
Grease will eventually harden and cling inside the pipes. It can combine with other debris to become a fatberg, leading to plumbing issues and costly cleanups.
Is it okay to flush tissues if I run out of toilet paper?
No. Tissues are designed to absorb water, not dissolve. They can cause a clogged drain fast. Use a trash can instead.
Sources
https://www.portland.gov/bes/safe-flush
https://www.bhg.com/home-improvement/plumbing/items-not-to-flush-down-the-toilet/
https://wastewaterts.com/16-things-you-should-never-flush-down-the-toilet/
https://www.fda.gov/drugs/disposal-unused-medicines-what-you-should-know/drug-disposal-fdas-flush-list-certain-medicines
https://www.epa.gov/household-medication-disposal/limited-role-food-and-drug-administrations-flush-list
https://www.mmsd.com/what-you-can-do/what-not-to-flush
https://www.rfmu.org/1015/What-Not-to-Flush
