Excess Sodium in the Blood in Cats
Excess Sodium in the Blood of Cats in Cats - Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost
What is Excess Sodium in the Blood?
Your veterinarian may refer to excess sodium in the blood of cats as hypernatremia. This electrolyte imbalance is commonly the result of excess sodium consumption, dehydration, an underlying acute condition, or chronic disease.
Excess sodium in the blood of cats, or hypernatremia, is an electrolyte imbalance. Since sodium is an electrolyte that plays a role in many body systems, your cat can begin to act strangely when sodium in the blood exceeds normal levels. If you suspect your cat suffers from excess sodium, contact a professional to prevent permanent brain damage, kidney damage or death.
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Symptoms of Excess Sodium in the Blood in Cats
Sodium is an important electrolyte that plays a major role in your cat's fluid balance. Sodium also regulates several organ systems and reactions integral to metabolism and brain function. As a result, excess sodium can manifest as a number of seemingly unrelated symptoms, such as:
  • Excessive thirst
  • Lethargy
  • Poor appetite
  • Weakness
  • Seizures
  • Behavior changes
  • Internal bleeding
The symptoms of excess sodium in the blood of cats are common to many disease states. At the same time, depending on the underlying cause, your cat may exhibit a different set of symptoms as a result of this electrolyte imbalance. For this reason, it is extremely important to have a professional (i.e., your cat's veterinarian) perform diagnostic tests to confirm excess sodium in the blood is the true cause of your cat's symptoms.
Causes of Excess Sodium in the Blood in Cats
Generally speaking, there are two major causes of excess sodium in the blood of cats, excess sodium intake and excess fluid loss. Within those categories, there are several major causes of feline hypernatremia. The most common are: 
  • Salt Poisoning: Salt poisoning is simply the excessive intake of sodium-containing foods or liquids. Usually, salt poisoning is diagnosed in critically ill cats who are receiving concentrated intravenous fluids. This is not a very common cause of hypernatremia in cats, however. Much more common causes of feline hypernatremia are related to the production of excess sodium within your cat's body or the excessive loss of fluid.
  • Dehydration: Simple dehydration is a common cause of excess sodium in the blood of cats. Sometimes cats become dehydrated due to a lack of available water. Other times, a hormonal imbalance prevents cats from feeling thirsty and seeking out water when they are dehydrated.
  • Fluid losses: Cats can lose fluid in a number of ways. Panting, as with fever or overheating, can cause fluid loss through the respiratory tract. Diuretic use, common in cats with diabetes, may lead to fluid losses through the urinary tract. Diabetes insipidus, a hormonal imbalance, can also lead to excessive urinary fluid loss.
  • Acute illness: Acute illness, especially bacterial infection leading to nausea, vomiting, and diarrhea, can lead to excessive gastrointestinal fluid losses.
  • Chronic disease: Chronic kidney disease and diabetes can both lead to insufficient or excessive urination. This alters the ratio of sodium to fluid in the blood. Chronic kidney disease can also lead to sodium retention by the kidneys, which concentrates sodium in the blood.
Diagnosis of Excess Sodium in the Blood in Cats
If you have reason to believe your cat is suffering from excessive sodium, it is important to contact a veterinary professional immediately, as this condition can be severe and even fatal. You can expect a veterinarian to test for excess sodium in the blood of cats by drawing blood and performing a hematological assessment. If your cat's sodium level exceeds 160 milligrams per deciliter of blood, your veterinarian will diagnose your cat with hypernatremia.
Since the symptoms of excess sodium in the blood of cats are common, your veterinarian may also choose to perform a differential diagnosis to eliminate other conditions, such as other electrolyte fluctuations or hormone imbalances. 
Depending on what your veterinarian suspects is the cause of excess sodium in the blood of your cat, he or she may perform other tests. Urinalysis or thyroid hormone tests could be ordered to diagnose diabetes, chronic kidney disease or hormone imbalances. By pinpointing the exact cause of your cat's hypernatremia, your veterinarian will be better able to treat and prevent the recurrence of this condition.
Treatment of Excess Sodium in the Blood in Cats
Most cases of excess sodium in the blood of cats will be treated with intravenous (IV) fluids to replace water or dilute sodium in the blood. This is an incredibly safe, effective and conservative approach to restoring sodium balance. Any further course of treatment selected by your veterinarian will depend on the underlying cause of your cat's excessive sodium levels.
If salt poisoning is suspected to be the cause, it is likely that your veterinarian will administer intravenous fluids to restore sodium-water balance and offer counseling to prevent future episodes of excessive sodium intake. If a gastrointestinal infection leads to vomiting and diarrhea, antibiotics may be administered. Chronic disease, such as diabetes or chronic kidney disease, will require more extensive treatment and long-term management. 
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Recovery of Excess Sodium in the Blood in Cats
Your veterinarian may counsel you on strategies to prevent this condition from affecting your cat in the future. Future management will depend on the cause of your cat's hypernatremia. If salt poisoning or dehydration are suspected to be the cause, a veterinarian might instruct you to make fresh water available to your cat at all times. Infection prevention, antibiotic treatment and medication management may also be discussed. If your cat's excessive sodium levels are the result of chronic disease, more extensive management specific to that disease state will be required.
Excess Sodium in the Blood Average Cost
From 418 quotes ranging from $200 - $1,500
Average Cost
$800
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Excess Sodium in the Blood Questions and Advice from Veterinary Professionals
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Tabby Cat
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Fourteen Years
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7 found this helpful

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7 found this helpful

My pet has the following symptoms:
Severe Thirst - Weak Back Legs
Our 14 year old cat has been diagnosed with Hypernatremia. He has always liked to drink from the faucet, but now he wants to almost every 30 minutes or so and even wakes us at night to turn the faucet on for him. He will not drink from a water bowl or fountain. He still has an appetite and eats a good amount. Our main concern is that his back legs are getting weak. I have attached further info that won't fit here as a photo attachment. Thank you!
Sept. 28, 2020
Answered by Dr. Michele K. DVM
7 Recommendations
Thank you for your question. I agree that the best treatment for him at this point would be subcutaneous fluids, or IV fluids in hospital if he is not stable. There may be other causes for his hind end weakness, and that would be something that a recheck examination with your veterinarian may help with, as I cannot see or examine him. I hope that the fluids help him overall, and he stays healthy for quite a while longer!
Oct. 5, 2020
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Siamese
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kalypso
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10 Years
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3 found this helpful

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3 found this helpful

My pet has the following symptoms:
Decreased Energy, Decreased Thirst
Hello my cat (10y. siamese) never drinked enough water, so once a day I feed her wet food mixed with water. We visited the vet, which said she looks dehydrated and advised to increase water intake and performed blood and urine tests which he finds ok. However, I see increased sodium and after I asked about it he said it is mild hypernatremia, so it is ok. What do you think? Could it be due to dehydration and insufficient water intake or do you think we should perform further tests and what exactly? Thank you very much in advance. Here are results: Biochemical analysis: Blood Urea Nitrogen (BUN) 24,09 mg/dl (19-32) Calcium ionized 1,27 mmol/l (1,10-1,30) Calcium total 10,9 mg/dl (9,40-11,60) G-GT 0,0 IU/L (0-9) Creatinine 1,61 mg/dl (0,90-2) SGOT-AST 44 IU/L (44-82) Sodium 181 mmol/l (140-160) Potassium 3,7 mmol/l (3,50-5,50) Urine analysis: Specific Gravity : 1027 pH : 6.0 Protein : No Hemoglobin : +++ Blood analysis: HCT Hematocrit 32,6 % (30-45) RBC Red blood cell count 6,48 x10^6/μL (5-10) HGB Hemoglobin 11,0 g/dL (9-15,10) MCV Mean corpurscular Volume 50 fl (41-58) MCH Mean corpurscular Hemoglobin 17,0 pg (12-20) MCHC Mean corpuscular Hgb concentration 33,8 g/dL (29-37,50) WBC White blood cell count 5,85 x10^3/μL (5,50-19,50) NE Neutrophils count 3,67 x10^3/μL (2,50-12,50) NE Neutrophils 62,8 % (35-78) LY Lymphocytes count 1,28 x10^3/μL (0,40-6,80) LY Lymphocytes 21,9 % (20-55) MO Monocytes count 0,21 x10^3/μL (0,15-1,70) MO Monocytes 3,7 % (1-4) EO Eosinophils count 0,67 x10^3/μL EO Eosinophils 11,5 % (2-12) BA Baseophils count 0,00 x10^3/μL (0-0,10) BA Baseophils 0 % PLT Platelet 376 x10^3/μL (175-600) MPV Mean Platelet Volume 11,9 fl (7,60-10,80) Hormones: Τ4 total 2,19 μg/dl (0,60-5) Free T4 1,26 ng/dl (0,60-2,60) TSH 0,11 ng/ml (0,30-5)
July 30, 2018
Answered by Dr. Michele K. DVM
3 Recommendations
My thoughts on that lab work, without knowing anything more about Kalypso, are that her increased sodium is probably due to mild dehydration, but in the face of mile dehydration, her urine specific gravity and HCT are lower than expected. In a 10 year old cat, I would be concerned about underlying kidney function, and might have an SDMA test performed to assess kidney function.
July 30, 2018
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house cat
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Dewey
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9 Years
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2 found this helpful

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2 found this helpful

My pet has the following symptoms:
Lethargy
Vomiting
High Sodium
Low Globulin
Low Total Protein
Low Mch
I have an 9YO male cat, neutered. History of scratching the back of his head until it bleeds and was on steroids for a period of time to treat this. The issue went away for a few years but is back - he's also had a history of seizure-type episodes. As of three months ago, he started experiencing breathing problems which they attributed to fluid outside of his lungs and prescribed a diuretic. This has been constipating him, leading to a second vet visit and prescribed laxatives after more breathing problems. They thought because of the test results the fluid was likely a problem with his heart and not his lungs and gave him a medication for that (they said this was a good thing). Now he's having trouble breathing again. He has little interest in food or water and has vomited clear fluid. Up until three months ago, his only issues seemed to be neurologic and the rapid decline in his health means a formerly slightly overweight cat is now 7.5 lbs (he was the runt of his little, so has always been overall small). On and off he has had trouble sitting down on his hind legs. Is any or all of this related? What's wrong with my cat???
July 2, 2018
Answered by Dr. Michele K. DVM
2 Recommendations
I can't say what might be going on with Dewey without seeing him and knowing more about him, unfortunately. It would seem to me that the scratching and seizures are probably not related to this new condition, and diuretics don't tend to cause constipation, and he may have intestinal problems. Since you are not seeming to have a clear diagnosis for Dewey, it might be worth either asking for more details from your veterinarian on what they think is going on, or seek a second opinion.
July 3, 2018
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Domestic Shor
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Adolfo
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13 Years
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3 found this helpful

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3 found this helpful

My pet has the following symptoms:
Thirsty
Thirsty Sodium
Hello, my cat started drinking water excessively about 6 - 7 days ago. He began throwing up his food and water as well. He licks at his food but barely eats. The water he drinks, he will throw up shortly after. I went to the vet today had him examined and all blood work was good (liver, kidney, diabetes, etc). However, he had a sodium level of 166 mmol/L. He growls if you touch his tummy area, During his exam at the Vet's he also growled and was very uncomfortable. This is very unusual behavior for him, he is normally laid back and lovely. The vet gave him a Convenia injection and a Cerenia injection and suggested I monitor him, since there is no conclusive evidence of anything else wrong except the high sodium level (besides not eating, excessive drinking and throwing up). I am very concerned and hope you might be able to help me with another tip. The kitty was "dumped" in our canyon about 3 miles off a main road. He had a bad eye, which we had to get removed and is approx. 13 years old. I have had him 5 months and know nothing else about his history. Apparently the eye condiiton was due to fluid build up caused by clogged drainage canals in the back of the eye. Very swollen and painful. Anyway, don't mean to be rambling on but I am reaching for any straws that might help me with the high sodium. Could it be bad cat food? Feed him wet canned food, ALL varieties and companies. Try to get grain free as much as possible. Thank you so much in advance! Isa
Dec. 19, 2017
Answered by Dr. Michele K. DVM
3 Recommendations
Thank you for contacting us about Adolfo today. I'm sorry that he is having problems, and appreciate that you are giving this cat a good home. Sodium can increase normally if he is dehydrated at all, which he may be given his behavior. It is positive that the rest of his bloodwork is all normal. If your veterinarian hasn't taken x-rays or done an ultrasound, those would be the next things to do in my mind, although I haven't examined him, and it would be best to discuss these tests with your veterinarian.
Dec. 19, 2017
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Domestic cat
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Rex
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7 Years
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2 found this helpful

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2 found this helpful

My pet has the following symptoms:
We Found Our Healthy Cat Had Passed
Not Aware
We found our healthy cat had passed away in the morning lying on the carpet, mouth open and tongue out, pale gums. The vet thought it might be a blood clot but could not be sure. The cat had no sign of illness, had a check up at the vet 3 weeks before and was perfectly fine the night before. However we suspect he may have eaten a tiny piece of salted walnut which was left in the kitchen. Could this be enough to cause his death within 4 hours
Dec. 8, 2017
2 Recommendations
Walnuts are not toxic for cats, but can cause some belly ache; salt is more problematic but I doubt that the amount of salt on the walnut is adequate to cause death in a cat as the toxic dose of salt is measured in grams and not milligrams. I would request a necropsy to look for signs of death as this may help give you some level of closure. Regards Dr Callum Turner DVM
Dec. 8, 2017
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Excess Sodium in the Blood Average Cost
From 418 quotes ranging from $200 - $1,500
Average Cost
$800
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