Is Scented Litter Bad for Cats? What the Research Shows

Is scented litter bad for cats? It isn’t poison, but it’s not the neutral choice it seems either. Vet guidelines consistently recommend unscented litter, and one study linked scented litter to cats going outside the box. Here’s what the research shows and when a switch makes sense.

What Vet Guidelines Say About Scent

The main feline veterinary bodies are clear on this. The AAFP and ISFM guidelines on house-soiling note that cats often find scented litters and litter deodorizers offensive, and recommend unscented clumping litter. The Cornell Feline Health Center says most cats prefer unscented litter.

Fear Free, whose article was reviewed by a board-certified veterinary behaviorist, goes a step further. It says cats prefer unscented litter whether the scent is added or natural, such as pine. It also notes that cats have two to forty times as many smell-receptor cells in their noses as people do.

That’s the key point. A scent that seems light to you can be strong to a cat, especially one that has to put its nose right into the box.

What the Research Actually Shows

The studies are fewer and messier than most articles admit. Some are peer-reviewed, some were only presented at conferences, and some are small. Here’s what each one found and how much weight it deserves:

Read together, the studies point to a mild preference for unscented litter rather than a strong one. In the 2011 data, more cats preferred unscented, but plenty were happy either way. The smallest study found no scent effect at all.

The Horwitz finding matters most. In a group of cats referred for house-soiling, scented litter showed up significantly more often than among cats without problems. That doesn’t prove scent caused the soiling, but it’s a reason to rule scent out when a cat starts going elsewhere.

Are Fragrance Oils in Litter Toxic?

This is the worry behind a lot of searches, so it’s worth being precise. VCA Animal Hospitals explains that cats are especially sensitive to essential oils because they have fewer of the liver enzymes needed to break them down. Its list of oils that can poison cats includes citrus, cinnamon, peppermint, pine, tea tree and wintergreen.

VCA’s warning is about concentrated oils, such as liquid potpourri or oil spilled on fur. It doesn’t mention cat litter, and I found no published cases of cats poisoned by scented litter used normally. Pine litter is made from wood, not concentrated pine oil, which is a different thing from the oils on VCA’s list.

Still, the cautious choice is easy. If a litter lists essential oils such as lavender and your cat grooms a lot or has health issues, pick an unscented version. World’s Best, for example, sells both unscented and lavender formulas.

We started on a scented Fresh Step formula. I found the fragrance too strong, so we switched to the unscented version, and both cats kept using the box without any problems.

Signs Scented Litter Doesn’t Suit Your Cat

Most cats show you when a litter bothers them, if you know what to look for. Watch for these signs after a switch, or with a scented litter you already use:

• Going next to the box instead of in it.
• Perching on the rim rather than stepping into the litter.
• Hurrying out without digging or covering.
• Sneezing after using the box.
• Red or irritated skin on the paws.

Horwitz also found that covering behavior differed between cats with and without soiling problems. OKC Vet Campus advises switching to unscented litter if a cat sneezes or shows skin irritation. Going outside the box can also be a sign of a medical problem, so call your vet if it doesn’t settle after you switch. Cornell and the AAFP both treat a sudden change in toilet habits as a reason to check for illness.

If accidents continue, my guide on why cats go outside the litter box walks through the medical, box and stress causes in order.

How to Switch From Scented to Unscented

Switch slowly, even to a litter your cat should like better. The Cornell Feline Health Center recommends mixing small amounts of the new litter into the old rather than changing all at once. Increase the share of new litter over a few changes until the old litter is gone.

Keep everything else the same during the switch, including the box, its spot and the litter depth. Choose an unscented litter that actually is unscented, since some bags labeled that way still smell of perfume. My guide to unscented cat litter lists which ones passed our sniff test.

In our case, the switch from scented to unscented Fresh Step went smoothly, and both cats kept using the box.

Unscented Litter Still Controls Odor

Many people buy scented litter to stop the box from smelling. Fragrance only covers the smell, though. Odor comes from ammonia made when bacteria break down urine left in the box, and an unscented litter that clumps firmly lets you remove that urine every day.

Activated carbon helps too, and Litter-Robot’s summary of Neilson’s research reports that cats preferred carbon to baking soda as an odor additive. My guide to the best cat litter for odor control compares litters on ammonia readings and absorbency rather than perfume.

The Bottom Line on Scented Litter

Frequently Asked Questions

Is scented cat litter toxic to cats?

There’s no evidence that scented litter poisons cats in normal use. VCA warns that cats are sensitive to concentrated essential oils because they have fewer of the liver enzymes needed to break them down, but its warning covers oils and potpourri, not litter. The main concern with scented litter is that many cats dislike it.

Is lavender scented litter bad for cats?

It’s not known to be dangerous, but it’s not ideal. Vet guidelines note that many cats dislike scented litter, and VCA advises caution with essential oils around cats. If your cat uses a lavender litter happily, you don’t need to panic. If you’re choosing new litter, pick the unscented version instead.

Why do vets recommend unscented litter?

Because many cats find fragrance off-putting. The AAFP and ISFM guidelines say cats often find scented litters and deodorizers offensive, and Cornell says most cats prefer unscented. Fear Free adds that cats have two to forty times as many smell-receptor cells as people, so a light scent to you can be strong to them.

Can scented litter make cats avoid the box?

It can for some cats. A 1997 study by Horwitz found scented litter significantly more common among cats referred for house-soiling than among cats without problems. That’s a link rather than proof, but if your cat starts going outside the box, switching to unscented litter is an easy first step alongside a vet check.

Do cats like any scents in their litter?

Research summarized by Litter-Robot suggests cats lean toward unscented litter, accept cedar, fish and bleach smells better than most, and tend to avoid citrus and floral scents. Those findings weren’t peer-reviewed, so treat them loosely. If you do use a scent, watch your cat’s reaction and switch back if it hesitates.