Colour changing cat litter can help monitor changes in your cat's urine, such as abnormal pH balance or possible signs of blood. It is a recent innovation that is helping owners take control of their cats' wellbeing, but is it all it's cracked up to be?

In this guide, we walk you through everything you need to know about colour changing cat litter and give you some no-nonsense information to help you make a decision about it.

What Is Colour Changing Cat Litter?

Colour changing cat litter is a type of health-monitoring cat litter designed to react to changes in a cat's urine. In most cases, these products use pH-sensitive indicators that change colour when urine is more acidic or alkaline than expected. Some also help identify possible signs of blood in urine.

As the owner, you won't need to do anything different with this cat litter. It is used just like any other litter — you pour it into the tray and cats urinate on it. But it will change colour depending on the urine's characteristics.

The main appeal of this for cat owners is that it can make it easier to spot possible signs of ill health early. Without it, barriers to this include:

• Cats hiding signs of illness
• Urinary issues being difficult to spot until they become severe

With colour changing cat litter, you get an early warning sign to seek veterinary advice. Just bear in mind that these cat litters are not diagnostic tools — they should merely prompt you to get your cat looked at by a vet.

How Does Colour Changing Cat Litter Work?

Most colour changing cat litters work through colourimetric indicators. These are substances that visibly change colour when they come into contact with urine of different acidity or alkalinity. Urine pH is the measure of how acidic or alkaline the urine is — a lower pH means more acidic urine, while a higher pH means it is more alkaline.

Cat urine pH can vary depending on a number of factors, including:

• Diet
• Hydration
• Stress
• Bacterial activity
• Urinary crystals
• Kidney or bladder problems
• How long the urine has been sitting in the tray

Colour changing cat litters use materials like silica gel crystals, paper-based litter, tofu litter and corn fibre or other plant-based materials. Silica crystal options are popular because they absorb moisture, trap odours and allow colour changes to remain visible.

What Do the Colours in Colour Changing Cat Litter Mean?

Colour systems vary by the brand of litter, so owners should always check the instructions on their specific product. Litter Sense cat litter will change from yellow to light green, red, orange or blue/dark green. All these things mean something different:

• Yellow to light green: Healthy urine with a balanced pH.
• Red: Blood detected in urine. Could indicate bladder stones or a UTI — contact your vet to investigate.
• Orange: Highly acidic urine. This could signal issues like kidney stones, urinary crystals or kidney disease. Consult your vet to investigate.
• Blue to dark green: A high pH level could indicate a UTI or risk of struvite crystal formation, which can cause blockages.

Remember, a single colour change doesn't automatically mean your cat is ill. But repeated or strong changes should be taken seriously, and it is recommended that you contact your vet and book an appointment to get your cat checked.

Why Cat Urine Health Matters

Urinary health is a major part of overall feline wellbeing. Cats can develop a number of urinary and kidney-related problems including UTIs, feline lower urinary tract disease, bladder inflammation, struvite crystals, kidney disease and more.

Urinary problems may be more difficult to detect because cats are very good at hiding pain or discomfort. Male cats, in particular, are at major risk from urinary blockages because their urethra is narrower. A blocked cat may be unable to pass urine — this is a veterinary emergency.

Look for the following symptoms:

• Straining in the litter tray
• Crying while urinating
• Repeated trips to the tray
• Passing only small amounts of urine
• Blood in urine
• Urinating outside the tray
• Excessive licking around the genitals
• Lethargy, vomiting or loss of appetite

If you notice any of these things, don't hesitate to contact your vet.

Benefits of Colour Changing Cat Litter

When you have colour changing cat litter, you do not have a comprehensive diagnostic tool. But you do have something that can provide early warning signs, help you monitor patterns, and offer a convenient daily health check.

Let's look at the key benefits of colour changing cat litter in detail:

• Early warning signs: The changing colours may alert owners to urine changes before obvious symptoms appear — particularly useful for cats with a history of urinary issues.
• Helps owners monitor patterns: Repeated colour changes can help owners describe changes more clearly to a vet — useful for monitoring older cats prone to bladder issues.
• Daily health check: This system works passively whenever the cat uses the tray and doesn't require the owner to collect a urine sample.
• Odour control: If the product is silica-based, it is designed to trap moisture and reduce ammonia smells. It may last longer than traditional clumping clay litter.
• Low dust: Health-monitoring litters are often marketed as low-dust, which suits cats or households sensitive to dusty litter.
• Peace of mind: Owners get a way to keep an eye on cat health between vet visits.

Drawbacks and Limitations of Colour Changing Cat Litter

While colour changing cat litter is an exciting innovation, it's important to note its limitations. It is not a diagnostic tool and can result in false alarms. Let's look at the criticisms that have emerged around health-monitoring cat litter:

• It cannot diagnose illness — only a vet can do this
• False alarms are possible, as various factors can affect urine pH
• False reassurance is also possible, as many health problems don't affect urine
• It is difficult in multi-cat households where several cats use the same tray
• Some cats dislike the texture — this can be the case for any cat litter type
• Tracking and dust can vary depending on which brand you choose
• Colour changing cat litter is usually more expensive than standard varieties, so you will need to weigh up the offerings

When Should You Contact a Vet?

As mentioned, colour changing cat litter cannot provide a definitive diagnosis of anything. But it can indicate that there may be a problem, potentially allowing you to get a diagnosis very early before your cat becomes very ill.

We recommend that you contact a vet if you notice any of the following:

• The litter repeatedly changes to any of the warning sign colours
• The colour change appears alongside behavioural changes
• Your cat is urinating more or less than usual
• The cat is going outside the litter tray
• You can see visible blood in the urine
• Your cat seems in pain, restless, withdrawn or unwell

Urgent veterinary care is needed if you notice your cat straining but failing to pass urine, or if they cry in the tray. The same goes for if they repeatedly enter the tray with little or no urine produced, or if they become lethargic, collapse, or refuse to eat.

Remember, urinary blockage can be a life-threatening condition, especially in male cats. Consider taking photos of the litter colour and noting when it happened, how often, and any other symptoms you have noticed.

Is Colour Changing Cat Litter Worth It?

Colour changing cat litter has been an invaluable resource for many owners, but it is important that you treat it as a monitoring aid rather than an actual medical test. It is best suited for older cats or cats with a history of urinary problems, particularly in single-cat households.

These cat litter products may be less suitable for:

• Cats that dislike crystal textures
• Multi-cat homes (unless trays are separated)
• Owners looking for the cheapest litter option
• Cats already under veterinary treatment where urine testing is required

We recommend that you introduce it gradually if your cat is fussy. Start by mixing a small amount with the current litter, then increase the amount slowly over several days. Always aim to keep the tray clean and accessible.

Remember, colour changing cat litter works best alongside normal observation. Keep an eye on appetite, thirst, toilet habits, coat condition, behaviour and energy levels alongside colour changes in the cat litter.

Final Thoughts: A Helpful Tool, Not a Replacement for Veterinary Care

Overall, colour changing cat litter can help owners notice urine changes at the earliest opportunity. With it, you can spot things that are otherwise undetectable — changes in pH balance or traces of blood in urine.

That being said, it cannot identify the exact cause and is not a replacement for veterinary care. If you use this cat litter and spot unusual colours, that should be a prompt to observe your cat closely and seek professional advice if changes persist or symptoms appear.

We all want the best for our cats, and proactive healthcare, early awareness and ongoing support for feline wellbeing are everything.

Frequently Asked Questions About Colour Changing Cat Litter

Can colour changing cat litter detect a UTI?

While it cannot diagnose a UTI, colour changing cat litter may show urine pH changes that can be associated with urinary problems. A vet may need a urine test to confirm the issue.

What does blue colour changing cat litter mean?

When the cat litter goes blue, purple or dark green, it suggests a high pH level. This could be associated with bacterial infection or struvite crystals — a vet will need to check.

What does red or pink colour changing cat litter mean?

Red or pink may indicate blood in the urine. If confirmed, this could be a sign of urinary tract disease, bladder inflammation, stones, injury or other medical issues.

Can I use colour changing litter in a multi-cat home?

While it is possible, it does make interpretation harder. If possible, use separate trays for each cat and try to identify which cat is responsible if a colour change appears.