8 Cleaning Products You Should Avoid Mixing

It’s hard not to be mesmerized by TikTok creators blending various cleaning products to tackle everything from bathtubs to kitchen counters. If you’ve ever found yourself watching these #productoverload videos, it’s easy to see why they’re so captivating. But before you get inspired to try it yourself, be warned: combining certain cleaning supplies can lead to disastrous consequences.

"Mixing cleaning chemicals can be highly toxic and dangerous. Generally, it’s best to avoid combining them due to the risk of harmful inhalation effects," says Kelly Krisna Johnson-Arbor, MD, FACEP, FUHM, FACMT, a medical toxicologist, co-medical director, and interim executive director of the National Capital Poison Center.

In addition, while some people may believe that mixing cleaning products can speed up the process or enhance effectiveness, Dr. Johnson-Arbor clarifies that this isn’t always the case. The idea that more is better definitely doesn’t apply here.

So, for your safety, stick to the basics and avoid mixing the harmful combinations of cleaning products listed below.

Toilet Bowl Cleaner and Bleach

Toilets can get pretty filthy, and sometimes a quick scrub with toilet bowl cleaner isn’t enough to get rid of all the grime. You may be tempted to add bleach to finish the job, but it’s best not to. Dr. Johnson-Arbor warns that this is a hazardous mix. “Combining toilet bowl cleaner and bleach can create chlorine gas,” she explains. “Inhaling either of these gases can cause coughing, throat and nose irritation, and difficulty breathing in healthy individuals. For those with asthma, COPD, or other respiratory conditions, inhaling these chemicals can lead to severe breathing issues and even be fatal.”

While not every toilet bowl cleaner may follow this rule, mixing bleach with any product is generally unsafe.

If you're exposed to any of these chemicals and have trouble breathing, Dr. Arbor-Johnson recommends stepping outside immediately to get fresh air. “If the symptoms of irritation continue for 10 to 15 minutes or if you have a history of asthma or other lung conditions, you may need to seek urgent care or visit an emergency room for specialized treatment,” she advises.

Bleach and Ammonia

Jenna Arkin, the chief innovation officer at ECOS, a brand of eco-friendly cleaning products, points out that there’s no federal requirement for ingredient disclosure on cleaning product labels. This often leads to consumers unintentionally mixing incompatible products. A common example is bleach and ammonia. “Chlorine bleach—found in products like whitening laundry detergents, toilet cleaners, and some disinfectants—when mixed with ammonia, often found in window cleaners, creates a toxic chemical reaction that releases chloramine gas,” Arkin explains. “In high concentrations, this gas can be fatal.”

While many bleach-containing cleaning products, such as mold removers, clearly highlight this ingredient on the front label, products with ammonia may not be as obvious. Always check the back label if it's not listed upfront. When unsure, choose ammonia-free alternatives.

Bleach and Vinegar

Mixing chlorine bleach, such as Clorox bleach, or bleach-based products like Lysol Mold and Mildew Remover With Bleach, with white vinegar, cleaning vinegar, or even non-toxic vinegar-based solutions like Aunt Fannie's Cleaning Vinegar can be dangerous. “When you mix bleach and vinegar—or any acidic product like toilet cleaner—it produces chlorine gas,” says David A. Walla, PhD, lead scientist at Defunkify. “This can cause coughing, breathing issues, burning sensations, and watery eyes.”

If you accidentally produce chlorine gas, Dr. Walla advises against attempting to “dilute it with water.” Chlorine gas reacts with water to form hydrochloric and hypochlorous acids, which are also irritating.

Instead, immediately remove yourself, your family, and pets from the area, get fresh air, observe your symptoms, and seek medical attention if necessary.

Hydrogen Peroxide and Vinegar  

Thinking about mixing hydrogen peroxide-based products, such as Lysol Multi-Purpose Cleaning Spray, with vinegar? Dr. Walla warns that this combination creates peracetic acid, which is not only highly corrosive but also harmful to the eyes, skin, throat, nose, and lungs.

Drain Cleaner and Bleach

If your pipes have a foul odor, you might think pouring bleach into the drain after using a cleaner will help eliminate the smell. However, Carol Mehas, the founder of eco-friendly cleaning brand Arbour, warns that this is a dangerous practice. “Combining these can trigger a lethal reaction in a confined space like a small pipe. Drain cleaners often contain lye (sodium hydroxide) to break down buildup and caustic potash to accelerate the destruction of organic matter like hair and soap scum,” she explains. “Since the drain is a small, enclosed area, the toxic gases formed during these reactions have nowhere to go but straight back up the drain into your shower.”

Mehas warns that inhaling this toxic mix can cause severe burns to your mouth and throat and could potentially lead to lung damage.

Different Brands of Drain Cleaners 

Clogged drains are frustrating, and if Drano doesn’t work, you might be tempted to try another brand, like Liquid-Plumr. However, cleaning and design expert Stefan Bucur of Rhythm of The Home advises against mixing these brands. “Some drain cleaners are alkaline-based, while others are acid-based,” Bucur says. “When combined, they can release chlorine gas, or even worse, cause an explosion.”

If the product you used isn't working, either pour more down the drain and allow it time to fully take effect, or consider calling a professional for assistance.

Bleach and Rubbing Alcohol 

If you're attempting to disinfect your bathtub or countertop, avoid mixing bleach with rubbing alcohol, as this combination creates chloroform. “This extremely toxic mixture can cause damage to the eyes, skin, liver, kidneys, and nervous system,” warns Dr. Walla.

Even if you're not using pure rubbing alcohol, be aware that many common cleaning products, such as Fantastik Multi-Purpose Cleaner, Clorox Wipes, and Lysol Wipes, contain this ingredient.

Oxalic Acid and Trichloroisocyanuric Acid

Oxalic acid-based cleaners like Bar Keepers Friend are excellent for removing stubborn food and grease from pans and stovetops. However, avoid combining them with products that contain trichloroisocyanuric acid, such as Ajax and Comet powders. “As with many dangerous cleaning product combinations, this can produce chlorine gas,” Bucur warns.