Dogs and cats are sometimes pretty similar to people. They’re social with us, have the same basic needs, and can wear clothes (when we dress them up).

But the similarities are only skin deep. On the inside, a dog or a cat has a very different system that yours or mine.

Here’s where that starts to be a big deal: pain medication.

Give your dog or cat the wrong pill to help arthritis or other pain and you might be sending your pet to an early grave. And it’s not just a dosage thing. It’s a chemical thing.

Here are the top human pain medications that you should not give to your pets.

Tylenol

This drug is commonly touted as one of the safest pain killers. And it is... for people. Not so much for cats and dogs.

Tylenol can cause liver failure and severe damage to red blood cells. If your dog or cat shows signs of toxicity: vomiting, difficulty breathing, facial swelling, or disorientation, get her to an emergency veterinary clinic right away.

On the whole, dogs are a bit less sensitive than cats. At least bigger dogs are, with their larger body-weight. A 50 pound dog being able to handle one or so Tylenol tablets before the drug levels became toxic.

A medium-sized cat could die from just one 250mg tablet.

As a rule, do not give your cat or dog Tylenol.

Ibuprofen

This is another safe-for-humans-but-deadly-to-pets drug out there. It’s a mild painkiller for us, but a plain ol’ killer for animals.

Ibuprofen causes stomach ulcers and kidney failure. If it’s not caught in time, it can kill. If you see your dog vomits along with having black tarry stools and shows general weakness, it may have ate some Ibuprofen.

If you give your pet ibuprofen and see these symptoms, it’s vet-time.

As a rule, ibuprofen with pets is a big no.

Motrin

Motrin is another name for ibuprofen. Same active ingredient. Different branding.

Even the junior strength version of Motrin still has 100mg of ibuprofen and is not safe for dogs and cats.

No Motrin for furry friends.

Advil

Once again, Advil is another name for ibuprofen. Strange, hey?

Wondering what the difference is between Advil, Motrin, and straight ibuprofen is? There isn’t really one.

Thinking of giving Rover of Patches some Advil? Think no.

Aspirin

Some pets can tolerate small doses of Aspirin. Its less lethal than the medicines above, but it’s still a really good idea to talk to your vet first. Best not to just start tossing chemicals into your cat or dog and hoping they work.

Your vet will evaluate your pet’s age, other medications, and sensitivities to see if aspirin can be handled. Even then, you might have to use baby aspirin.

Aspirin can cause stomach problems. Your vet may recommend using a coated version of the pill to treat arthritis pain.

Not every dog will tolerate aspirin well. Smaller dogs should only receive baby doses under veterinary care.

And cats? They metabolize aspirin slowly so are much more prone to overdose. Only give very low doses under veterinary care.

Cat aspirin overdose symptoms include loss of balance, vomiting with or without blood, diarrhea, depression, and mood changes. If you suspect your cat has ingested aspirin, seek immediate veterinary care. Aspirin overdose in cats can lead to death.

Watch out for aspirin with enteric coating. This kind of coating has been called a “hard candy” coating and changes how aspirin is absorbed in human bodies. In dogs and cats, it can set conditions for an overdose.

The ruling for aspirin is maybe, only with a vet.

Pet-safe Pain Relief

Rimadyl is one of a few safe drugs for pets. It’s formulated specifically for cats and dogs.

Many vets prescribe Rimadyl relieve pain due to osteoarthritis and hip dysplasia – both common to larger breeds of dogs.

With any medications, some risks remain inevitable. An overdose could lead to renal failure, gastrointestinal distress, vomiting, diarrhea, lethargy and seizure. An allergic reaction can lead to rash and swelling . Seek immediate veterinary care if you suspect an allergic reaction.

Cats can take Rimadyl in much smaller doses – about 1mg per pound. Some veterinaries do not prescribe Rimadyl for cats at all, though . Severe pain (post-operative, for example) can be treated with morphine-type drugs.

For joint pain related to aging and obesity, some vets simply opt for natural alternatives such as supplementing with glucosamine.

It’s important to check with a veterinary before attempting to treat your pet with human medication. You understandably want to soothe and comfort your beloved pet by any means possible, but doing so can come at a huge cost.

Reactions to ingesting medication can require overnight vet care, expensive treatments such as intravenous fluids, and further pain and suffering for your pet – and your wallet.

Did you know that cats are hard-wired to hide their pain?

It’s a carnivore thing. When in a survival or fighting situation, which happens a lot with animals that have to hunt to survive, showing weakness can be a sure-fire way to proclaim “I’m easy pickings.”

Of course for a house cat, not showing pain can get in the way of diagnosing important health-related issues.

Here’s some subtle ‘pain behaviour’ to watch for.

1. Less Fun

Cats love to jump on perches and chase after toys. Even into their geriatric years, many cats still enjoy playing and jumping. If your cat suddenly stops jumping on the couch to sit on your lap, that may be a sign.

2. More Hiding

Instinctively, a cat tries to hide when in pain. It is a survival strategy. Recognize when your cat is acting more independent than usual. Hiding under the couch or behind the television are signs of either fear or pain.

3. Less or No Grooming

Grooming requires maneuvering and bending and flexing. A cat in pain won’t be motivated to bend and twist like that.

Overweight cats might face additional challenges, when a big belly gets in the way of reaching certain areas. A lack of grooming can also indicate sore gums or mouth problems.

4. Cat Accidents

Has your cat always been good with the litter box, but has suddenly stopped? He is trying to tell you something. If you recently moved the box, it may be too high or in an awkward place. If your cat has painful joints and has to climb stairs to reach the litter box, this could indicate a problem.

5. Loss of Appetite

Sure, it might be that your cat is a picky eater. But, a sudden loss of appetite could mean an illness. Lack of interest food could mean intestinal problems, pancreatitis, kidney problems or even cancer. Visit the vet to check up on problems like these.

6. Fast Heart Rate or Rapid Breathing

This is hard to notice, but it could indicate a serious heart condition. Cardiomyopathy occurs in certain breeds of cats more often – such as the American shorthair. It can make your cat listless, have a poor appetite and you may even see paralysis of the back legs.

7. Dilated Pupils

Again, this could be hard to notice, but if you see a trend overtime then it could be a sign of hypertension. Since hypertension is often a secondary condition, this could also mean that your cat has kidney problems or even hyperthyroidism.

8. Flinching

A flinch away from you when you pet your cat might mean something. A normally affectionate cat does not suddenly stop cuddling for no reason. The best thing to do is not to force affection onto your cat. If you’ve noticed a change in how affectionate your cat is, that might mean it’s time to see the vet.

9. Loudness

Often, cats will chat a little more to let you know that you have neglected a feeding. Unfixed cats will also make some bizarre noises when it’s mating season. Know and recognize your cat’s various types of meows and what they mean. Anything abnormal or excessive noise could mean pain.

Since you won’t be able to diagnose whether Tiger’s problem stems from anxiety, a behavioral or an underlying physical illness, it’s important that you book an appointment with your vet right away.

One cat-owner woke up to her cat howling and found that he had crystals – a painful urinary tract problem that often shows up in male cats.

10. Irritability

If your cat stops being social then that could mean something. Cats often show irritable behavior when they are uncomfortable. If could be a bodily thing like a joint problem or paw problem, or it might be dental.

Either way, if your cat stops doing his normal things – like sitting on the chair beside you at dinner or sleeping on your head at night – consider what it might mean.

You know your cat better than anyone. You can tell when he or she isn’t acting normally.

In general, weird or abnormal behaviour could mean pain. If you notice something strange, a visit to the vet couldn’t hurt. Even if it’s just for a check-up.

When your dog has puppies, it's extra-important to make sure you know what's going into her system, and into her puppies! Of course, 'Mom' has to want to feed her puppies first...