Over the years, I have seen many cats whose owners were worried about their noses. One of the more common concerns that leads cat owners to seek veterinary attention for their pets is a dry nose. Most people generally believe that cats’ noses should be cool and moist at all times. And, indeed, most cats do have cool, moist noses. A dry cat nose might occur if a kitty is dehydrated or suffering from a fever — or a dry cat nose might not be problematic at all.

So, although there is a loose correlation between a cool, moist nose and good health, some perfectly healthy cats have warm, dry noses. And although a dry cat nose may be correlated with fever or dehydration, the nose is not the best way to assess for these things. There is only one accurate way to test for fever: taking a rectal temperature. (Ear thermometers exist for cats, but sadly in my experience they are not reliably accurate.) The best ways to test for a dehydrated cat are to assess skin turgor (elasticity) and to assess the thickness of the saliva in the mouth. Both of these ways of assessing hydration are subjective, and a great deal of experience with hundreds or thousands of cats is necessary to become proficient.

Dry cat nose — should you be concerned and when?

If your cat’s nose has always been warm and dry, it’s very unlikely that there’s anything to worry about. If your cat’s nose is usually cool and moist, and then suddenly becomes warm and dry, your cat may have a fever or be dehydrated (or both — fever almost invariably leads to dehydration in cats). Or not. Sometimes the nature of cats’ nasal secretions varies, fluctuates, or changes permanently over time.

If you are worried about your cat’s dry nose, the safest thing is to have a vet check him. However, you can take his temperature at home (normal feline temperature is 100.0 to 102.5 degrees Fahrenheit). And if you know what you’re doing, you can properly assess him for dehydration using other methods.

Since most people don’t have the experience to properly assess for dehydration, and most people don’t have the desire to insert a thermometer into their cat’s rectum, you can also use another trick. Dehydration and fever generally cause cats to feel sick. Lethargy and poor appetite are very common with either.

Any cat with a dry nose who is lethargic, has a poor appetite or seems sick in any way should see a vet. But so should any cat with those symptoms whose nose is not dry. It’s the lethargy, poor appetite and symptoms of illness that are of greater concern than whatever is happening with the nose.

A wet cat nose is actually more of a concern than a dry cat nose!

It boils down to this: A dry cat nose doesn’t always mean very much in cats. The opposite, however, is less true. A wet cat nose often does mean that something is wrong. A wet cat nose or a runny cat nose is a common symptom of upper respiratory infections (URIs) in cats.

Several dozen known viruses and bacteria cause URIs. There are likely dozens more that are not yet discovered, and probably thousands more that will eventually evolve. The two most common causes of URIs — a herpes virus and a Chlamydia bacteria — sound like sexually transmitted diseases but aren’t. Both of these organisms are ubiquitous. Virtually every cat on earth has been exposed to feline herpes (also called rhinotracheitis); like the cold sore virus in humans, infection with herpes is lifelong, with sporadic outbreaks, in cats. Therefore, even solitary indoor cats may suffer from intermittent URIs.

Although URIs earned their name for their respiratory symptoms, the eyes are often affected as well. Watery or red eyes are common in cats with URIs. However, a runny nose — often with an excess of seemingly normal clear discharge, but sometimes with mucus or even malodorous pus-like material — may be the first sign of a URI.

Is a wet cat nose always a sign of a URI?

If your cat’s nose is wetter than normal, he may be about to break with a URI. However, if he is not showing any other symptoms, then in most cases it’s not necessary to rush immediately to the vet. Careful observation, however, is always warranted.

If your cat receives injectable fluids (for instance, for kidney failure), then be aware that an excessively moist nose can be a sign of fluid overload. This condition occurs when the quantity of fluids administered is greater than the cat’s circulatory and renal systems can handle. The nose therefore should be monitored carefully in any cat receiving injectable fluids. If fluid overload progresses, potentially life-threatening respiratory difficulties can occur.

What about color changes on cat noses?

Finally, although it’s not related to moisture, be aware that sometimes the color of the nose may change in cats. This happens most frequently in so-called ginger cats, also known as orange tabbies. These feline redheads are prone to developing freckles on their gums, lips, eyelids, ears and noses. Although the condition has a scary sounding medical name (lentigo simplex), it is benign. Nose freckles are very common in orange cats, and they tend to accumulate with age. Unlike solar-induced human freckles, however, they almost never convert to cancerous lesions.

Cat noses might also slightly change color from time to time — which usually isn’t a cause for concern, either.

Thumbnail: Photography by _Runis_/Thinkstock.

Read more about cat noses on Catster.com:

• 5 Remarkable Facts About Cat Nose Freckles
• 4 Cool Facts About Cat Noses
• 8 Interesting Facts About Your Cat’s Nose and Sense of Smell