Sometimes disease processes make it difficult for a pet to stay hydrated, even if a pet is drinking plenty. Those of you savvy about diabetes understand this all too well. If a pet’s blood glucose is so high that it prevents the kidneys from recapturing fluid after the kidneys filter the blood (that’s essentially what kidneys do to make urine), a pet can become dehydrated even when drinking large amounts of water. Kidney disease is another situation where it might be difficult for a patient to stay hydrated. Or if a pet has fluid losses such as from diarrhea or vomiting we might also need to help hydrate a pet.Catching Up On Hydration

What does it feel like to be dehydrated?

I’ve never been stuck on a dessert island nor deprived of water for extended periods of time, but I know what dehydration feels like. I’m as far from a party animal as they come, but despite my nerd-self, I have had a few times when I’ve had too many cocktails. The next morning’s hangover feeling is mostly due to dehydration. When we are dehydrated we feel puny. We aren’t as able to combat illness. Really, nothing works quite right when we are dehydrated.

So what are the hydration options to rehydrate a pet?

Oral: Oral hydration is the best option if there is no vomiting and the pet is just mildly dehydrated. If the gut works, use it! Really, Mother Nature intended us to imbibe our fluids. Our gi tract cells thrive with normal use and wither when not used.

IV: Unfortunately, if a pet gets behind the eight ball and becomes moderately to severely dehydrated, the quickest route to feeling better is IV fluids. This means setting an IV catheter (small soft plastic tube) into a vein and administering a balanced electrolyte solution right into the bloodstream. We can start with a quick fluid push, but then we need to slow down the fluid rate or else bad things can happen. Even when we are aggressively rehydrating a patient, we must reevaluate the fluid rate frequently. Sometimes we will spike the bag of IV fluids with additives such as potassium chloride.

I place sick pets on IV fluids all the time. This week one pet owner asked if she could administer the IV fluids at her home instead of leaving her sweetie at my clinic for the day. Honestly I think the human was more anxious about leaving her pet than the pet was anxious! Nonetheless, if I do have an anxious pet I’m not above giving a little versed to decrease anxiety… to the pet I mean! I told this pet owner that unless she had medical training it probably wasn’t a safe option. Besides, while monitoring a pet’s hydration while on fluids, we also have fluid pumps in clinics that regulate just how much fluid is administered each hour. We wouldn’t want to over hydrate a pet after all. Let me tell you, over hydration is no fun! I once had sinus surgery and I bled, so I was kept overnight in the hospital. I won’t name names but my overnight nursing care was more overnight neglect. They had me on so much fluid that my wrists were double their normal size the next morning. I was doped up on a morphine drip, and I peed the hospital bed overnight. Humbling moments! My point is, we need to monitor how a pet is doing while on IV fluids.

SQ: Sometimes vets use “SQ fluids” if time or finances don’t allow hospitalization on IV fluids or if a pet is just mildly dehydrated. To administer SQ fluids, we pick up the scruff and insert a needle into the subcutaneous space. We administer a balanced electrolyte solution under the skin. This is the same type of fluid that we usually administer intravenously, but give it under the skin instead. This fluid usually sinks under the armpit or to the ventral chest just by gravity. Usually within a day or so the lymphatic system will absorb the fluid. It’s not usually as good as IV fluids for hydration, but it’s still a feasible option!

You know I like hearing from our readers. Don’t hesitate to email me at

NOTE: Consult your veterinarian first to make sure my recommendations fit your pets special health needs.

Dr . Joi Sutton

Dr . Joi Sutton

Dr. Joi Sutton is a 1993 graduate from Oregon State University. She has practiced both in emergency medicine and general practice. Dr. Sutton has done extensive international volunteer work though Veterinary Ventures, a nonprofit organization that takes teams of veterinarians to undeveloped countries for humane medical care. She also runs a small animal practice in South Florida.
Dr . Joi Sutton

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