Cat outside litterbox
You get that postcard in the mail reminding you that it’s time for Baxter or Snowball’s regular checkup. He looks fine, you think to yourself, and he’s up to date on his vaccinations. I bet we can put that off for a while.

Think again. Even if your dog or cat doesn’t need vaccinations, his regular exam — especially as he gets older — helps to ensure that no serious problems lurk beneath what seems like a healthy exterior. Pets can develop a number of health problems that you may not even know were there without a veterinary exam (and maybe some diagnostic tests). Here are a few of them that can trick you or even go unnoticed until the condition is far advanced.

Hyperthyroidism

“Wow! Look at Lucy race around the house! You’d never know she was 11 years old.”

If your senior cat has a lot of energy, you might be patting yourself on the back about what great shape she’s in. She may be, but what’s also possible is that she has developed hyperthyroidism, an excess of thyroid hormones in the blood. It’s a problem we usually see in aging cats. Other common signs include weight loss and an increased appetite. So though you think your cat is active, eating well and not overweight, what’s actually happening is that she may be on the road to developing high blood pressure, heart failure, sudden blindness, and chronic vomiting and diarrhea. Left untreated, hyperthyroidism can lead to death.

The good news is that hyperthyroidism is treatable for some cats and manageable for others. The disease can be managed with a daily pill or special diet, or cured with radioactive iodine treatment or surgical removal of the thyroid glands.

Hypothyroidism

This disease, a deficiency of thyroid hormone, is the opposite of hyperthyroidism. It usually affects middle-aged and older dogs.

Signs of hypothyroidism tend to be vague. If you notice anything at all, it might be that your dog is less energetic; seems to get infections more frequently; or has a ratty-looking coat that seems dry, scaly, itchy or greasy. He may gain weight, even if he’s not eating anymore. On exam, your veterinarian may notice a slower heart rate.

Like hyperthyroidism, hypothyroidism is diagnosed with a physical exam and blood test. It, too, is manageable with daily medication.

Kidney Disease

Your senior cat has been peeing outside the litterbox — a lot. He must be mad at you, because you’ve been working late, right?

Wrong. “Stinking outside the box” can be a sign of many different health problems, but in an older cat it may well signal kidney disease.

Kidney failure is a common problem in older cats. Clues to its presence include drinking more water than usual and then, of course, peeing more than usual — so much so that the cat may start to miss the box, because he can’t get there in time or it gets too full or smelly to suit him.

Though kidney failure can’t be cured — unless you can fork over the big bucks for a kidney transplant — it can be managed for months or even years with diet, medication and subcutaneous fluids, which you can learn to give at home.

Heart Disease

Heart disease isn’t the leading cause of death in dogs or cats, but it’s not uncommon either. It’s been estimated that approximately 10 percent of dogs develop heart disease, and valvular disease accounts for the majority of these cases. Dogs may also develop dilated cardiomyopathy.

Cats of any age can develop hypertrophic cardiomyopathy. The disease doesn’t discriminate: It affects alley cats and aristocats alike.

Signs of heart disease in your dog or cat that your veterinarian may detect during an exam can include a heart murmur, gray or bluish gums, noisy breathing and fluid buildup in the abdomen or lungs. It’s not curable, but it can sometimes be managed for months or even years with medication, especially when caught early.

Pain

Pain isn’t a disease, of course, but it accompanies many different diseases at all stages of life. Arthritis, dental disease, cancer, injuries and more can all cause pain in our pets, but we have to be really on the ball to notice it sometimes.

Pets are hardwired not to signal that they’re in pain. In the wild, showing pain could be a death warrant. They don’t know, of course, that we just want to help, so they do their best to hide discomfort, making it more difficult for us to realize there’s a problem.

With the laying on of hands through palpation and range-of-motion tests, as well as through recognizing subtle signs, such as a hunched back or an owner’s comments that Rusty is sleeping more, eating less or not jumping up on the sofa anymore, we can often pinpoint pain that your dog or cat is doing his darnedest to hide. He may need a dental cleaning, a weight loss program or medication to take the edge off those aching joints or reduce disease-related pain.

Next time you’re thinking of skipping or postponing your pet’s wellness exam — maybe you don’t go every year yourself — keep in mind that he ages more quickly than you and can’t speak up if he’s not feeling well. Then call your veterinarian and make that appointment. Whether you catch a problem before it’s far advanced or find out your pet is fit as a fiddle, you’ll both benefit.

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