Elevated liver enzymes in senior dogs- what does it really mean?

It happens quite often that I’ll run a blood panel on a seemingly healthy senior dog, and I discover one or two liver enzymes are higher than normal. How worried should we be? Well, it depends, but here’s some general patterns.

The usual culprit is an enzyme called Alkaline Phosphatase, or Alk-Phos, or Alk-P. I commonly see this enzyme rise in older dogs that have no symptoms. The other liver enzymes always seem to be behaving – it’s just this one that’s wonky. The normal range depends on the lab your veterinarian uses, but most consider anything up to 130 or so as normal. It’s not a shock at all to see a dog have an Alk-P of 200, even 400. My old dachshund mix has had an Alk-P over 300 for the last 3 years. He’s doing great.

This enzyme drives a lot of veterinarians crazy. We need to look at the whole dog, and the severity of the increase. For starters, if the other liver enzymes are normal, the dog has not lost weight, bloodwork is otherwise perfect, many veterinarians will simply recheck the blood in a couple months. If everything else stays in line, and the Alk-P is not rapidly rising, maybe even dropping, we’ll be happy, shrug our shoulders, and say we’ll keep tabs on it.

We get worried about Alk-P when it becomes drastically high, like 800, or 1,500. Then there’s probably something going on. One possibility is a disease of the adrenal gland called cushings disease. With this disease, the adrenal glands produce too much adrenaline, making the dog start drinking lots of water (think of a dog on prednisone), possibly have hair loss, and can even develop a pot belly. (Here’s my in-depth article on cushings disease). The excess adrenaline causes an increase in Alk-P, with other liver enzymes staying the same. I can’t tell you how many second opinions I get where the veterinarian did routine blood work on a healthy dog (senior screen, pre-anesthetic for a dental, etc), found a mild-moderate increase in Alk-P, and wants to diagnose cushings. That’s not how we diagnose cushings. Again, we have to look at the whole dog. If your dog isn’t drinking a lot, or showing any other symptoms, that high Alk-P is most likely not cushings.

What else can cause an Alk-P to elevate while the other liver enzymes stay the same? Liver tumors. I’ve seen both benign and cancerous masses on the liver causes this change in the bloodwork. One patient had a tumor the size of a volleyball on her liver. She had it removed at the specialist, her Alk-P went back to normal, and she went on with life.

Guess what else can cause an increase in this liver enzyme – severe dental disease! The liver is trying to filter all that infection, and it’s not pleased. I had an older dog that we drew pre-anesthetic bloodwork on for a dental cleaning. Her Alk-P was over 800, so we took notice! We had her abdomen ultrasounded, worried about putting a dog under anesthesia with a questionable liver. The ultrasound specialist said “how soon can you do the dental and get this liver happy?” So do not let an increase in liver enzymes prevent your dog from having a dental if he has significant disease! In this case, we ended up pulling many teeth (this dog had SEVERE dental disease) and when we rechecked the blood 2 months later, all had gone back down to normal!

dog, liver, veterinary

My Sam has had an Alk-P over 300 for a couple years now. He’s cool with it.

So if we get a really high Alk-P, an ultrasound of the abdomen (the liver) is a very good idea. What if it’s normal? Well, this is where it gets tricky. I have many dogs with elevated Alk-P on their bloodwork and very normal livers on ultrasound. Good news…but now what? The only way to get a 100% diagnosis of liver disease is with a biopsy. Yep, we have to cut a piece out of the liver and send it off to the lab. If your dog is acting sick, losing weight, or we know something ain’t right, this can be a great step! If your dog is healthy, happy, not losing weight, just had routine bloodwork done and has one elevated liver enzyme…do you want to go cutting into your dog? I’m not sure I would on my dog!

This is the point where I tell owners they are not terrible people if they choose to do nothing. Of course, if your dog decides to start showing any symptoms, we have a different story. But I can’t tell you how many healthy older dogs have mild-moderate increases in Alk-P and it never amounts to anything. There is a syndrome called vacuolar hepatopathy that can only be diagnosed on liver biopsy, but is common in older dogs…and doesn’t really do anything except cause these changes on the bloodwork. So for owners who want a name for the probable underlying cause that really isn’t much of a thing, we can say we suspect vacuolar hepatopathy….sure, why not.

What about other liver enzymes? If your dog has an increase in ALT (alanine transferase) then this could be different. I commonly see Alk-P rise in older dogs, but I not-so-commonly see ALT rise. If BOTH of these enzymes are high, then I would do some looking into it….literally….with an ultrasound. Again, if that shows no cancer or craziness, it doesn’t mean the liver is normal, just that it looks superficially normal. In healthy dogs, we’ll routinely recheck the blood in a couple months and see what direction these enzymes are going. I’ve had cases where I recheck and they are normal. Can’t explain what was going on, but we’ll take it! Other times, if they are on the rise, there’s something up. Sometimes I’ll add a medication I call the “happy liver pill.” Denamarin is the brand I use. It contains the tools the liver needs to repair itself, if it feels the urge. If the liver is not in a self-healing kind of mood, this supplement will not help. But if the liver IS in the mood, all the tools it needs are right there! This medication is well-tolerated in most dogs, so many owners take the “it can’t hurt!” attitude and try it.

The main two liver enzymes we look at on routine screens are Alk-P and ALT. There are a couple other players that tend to behave – GGT and total bilirubin. I rarely see an elevation in either of these without the main two first getting involved. These enzymes both loosely correlate to the gallbladder and bile ducts. If they are high, I take notice. Especially if they are part of a theme of all liver enzymes being high.

I of course can’t go into every possible liver disease here. This was more to help calm the nerves of the typical dog owner whose dog has some slight changes on the senior blood test. Sometimes there’s an underlying disease process, but many times there isn’t! I also do not let a little high Alk-P prevent a painful dog from getting arthritis medication. Again, we have to look at the whole dog here, and maintaining a good quality of life.

Bottom line – if your veterinarian tells you your otherwise healthy dog has a single liver enzyme that’s high and she’s not too worried about it, you shouldn’t be either. Rechecking blood in a month or two can tell us if we caught something early, or if this is our new normal. And if you want to make sure, an ultrasound of the liver is not invasive, doesn’t require anesthesia, and may rule out some scary things.

Posted in General health, Internal Medicine.


  1. I have a 10 1/2 year old Lab/Border Collie mix who had a senior panel blood workup done recently. Her Alk-P was 2,141 but all of the other liver enzymes were normal. Her overall health is good. The only thing to note would be the start of some hip and back discomfort, most likely arthritis. My concern is how high her reading is compared to the normal range. Could a reading this high be primarily the result of age/arthritis, or would this reading be excessively high with out other contributing factors?

    • Did you guys figure this out? My dog tested extremely high in alt (800) and mildly high in alp (300) today. She’s young (just turned 1 we think) and is usually hyperactive, but is clearly uncomfortable right now and not very active.

  2. Thank you for this insight. What a clearly written, informative, no non-sense article. I appreciate hearing your differential process, especially for the older dog. And the thought of *gasp* doing nothing in the absence of symptoms or other associated enzyme elevations? Refreshingly honest.

  3. My Dog is ALP is 400. Her calcium is also low and kidneys are ok. She is 7 year old beagle. Pls suggest how to lower her ALP.She is otherwise active dog.

  4. Thanks so much for a great, clear, and easy to understand article. My big Labrador Retriever is almost 14 years old, and almost 100 pounds. He is not overweight – he’s just really big. Anyway, two different veterinarians have tentatively diagnosed a slow-growing brain tumor, and he is on permanent high doses of prednisone. He can’t go off of it – he can’t get up, his head rolls around, etc. This week, his bloodwork showed an ALK-P of 826, and AST of 176. Is there something that we can give him to help his liver function better? I know that prednisone causes liver damage, but want to help him all that I can.

    Thanks so much for any help that you can provide.

  5. My 9 year old labradoodle blood work came back with the liveer numbers at 500. A few years ago,they were at 1000. We had him in the hospital at that point ad he did the tank thing and came home and was fine. He was on Melaxicam then. Sine then he’s been on Galiprant. Liver tests have been fine until last week. Noticed he had no appetite and drinking lots of water again. What is causing this?

  6. I have a 14 yr old Bearded Collie. Excellent health. Great heart, kidneys, etc. Did a blood work check, and liver was elevated. We are on antibiotic, and Liver Vitamins, and Ursodiol. Gunna check back in about a month. No weight loss, normal food and water consumption. Xray, looked normal across the board, so we will move on with an ultrasound, if things don’t come out the way we want in a month. No Cushing’s is expected.

  7. My 1.5 year old Corgi has 300 ALT for a month now, we did a full blood panel, and everything is fine except ALT, so I gave some Samylin for 2 weeks but ALT still at 300. Vet has no idea and wanted to try milk thistle for another 2 weeks, if no improvement, then an ultrasound. I am worried sick…

  8. Hi there!!

    I have 3 senior pups! A bichon shih tzu who has had cushings for 5 years, every single symptom shown! I think of myself as a cushings pro because of this! We also have a chocolate lab that just turned 11, she gets ear infections quite often so a new vet suggested blood work. We go ok, good plan! He calls me 2 days later saying her ALT is high and says we really should do a cushings test. This pup has ZERO cushings symptoms, literally not a single one! Move on to our next pup! A 10 year old spaniel shih tzu cross(we think) and she randomly gets glaucoma and we go from lots of meds to try to surgery and the eye has to come out! They want to do blood work so again we go yep! Of course! She’s getting surgery! They call us and tell us she has high alt!!! Again ZERO symptoms, not a single one in her either! I know one dog has it but there is no way all 3 do! Does brand of food have any effect on this? It was the only common denominator between the 2 asymptomatic pups, I switched their food from blue buffalo senior to science hills senior to help kidney and heart function but is there a good food for liver for older pups? Just seems too coincidental that all 3 especially 2 with no symptoms would instantly get the cushings label and the two with the recent cushings suggestion saw two entirely different vets

  9. My 11 year old Pomeranian has elevated liver enzymes of 502. Vet put her on Denamarin for one month and we will continue for another month. It was 677 before the one month on Denamarin. This was found accidentally with pre dental anesthesia blood work. She seems very healthy and energetic. The vet did an x-ray of her abdomen and all looks normal, no enlarged and no fatty liver. To my surprise, we found 3 rather large bladder stones in her bladder. These are scheduled to be removed in 10 days. My question to you is….
    Is it possible that perhaps the liver can be elevated because of the irritation of the stones ? She has no symptoms whatsoever.

  10. Hello My male doberman started with higher ALT 528 and ALK P 228 in May 2019. We retested in July 2019 and the numbers started coming down using ALT 372 ALK P 170 Now here we are in March 2020 & the blood work is showing a skyrocket ALT 1675 and ALKP 587. I see a holistic vet who added more liver support – Milk thistle was added and Cataplex E Hepctrophin PMG ; He was already taking other supplements prior zymex, AF Beta Food, LS Derma Gold, Catalyn GF(multi vit), and multizyme (digestive enzymes). Dr. also wants me to add zinc endo-met. Should I not wait another 8 weeks for new tests, should i get another vet to do an ultra sound. Is it too late for my dog is the liver already damaged beyond repair. Otherwise healthy not showing many signs he did throw up twice this week. I took him kibble around 6 months ago and feeding him raw diet trying to figure this raw diet out is this causing the problem he’s not liking the food as much?

  11. I have a 10 yr. old dachshund who was scheduled for a dental but her alt and alk-p were elevated. The alk-p was 2400. Dental was held and was on Clavacillin and Denamarin for 10 days. Alt and alk-p were redrawn. Alt is 442 and Alk-p was 3800. We were consulted for an abd ultrasound to be done. Will make the appt. tomorrow and hope to see the radiologist within the next few weeks to have it done. Dog is asymptomatic as far as I can tell. The only time she ever drinks water is right before she goes outside for walk or to pee. I was told it could be a tumor or Cushings. She is a sweet pup. Hope we can find out what is wrong.

  12. Hey there – just want to add some more positive news in the meantime.

    My dog has ALT in 300s (335) and ALP in 300s (304) with x-rays showing fluid in the abdomen, enlarged kidney and enlarged Pancreas with negative Pancreatitis. They were suspecting IBD and test results came back that she had Giardia. She is now on Denamarin and getting a retest in July, which doctor suggested it takes a couple of months for Liver Enzymes to go down. Still waiting for the test but she seems to be doing really well and is now on Science Diet I/D in the meantime. Will update when we hear back in July, but make sure you test for Giardia

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