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Featuring Demian Dressler, DVM and Sue Ettinger, DVM, Dip. ACVIM (Oncology), authors of The Dog Cancer Survival Guide

Surgery and “Blood Thinning” Drugs and Supplements

Updated: November 15th, 2018

The approach in The Dog Cancer Survival Guide, as well as my own personal philosophy concerning problem-solving, is to use what works, regardless of the packaging material.

In other words, it makes no difference if the recommendation comes from a conventional (allopathic) vet, or an “alternative” vet, as long as it works, is safe and gives some advantage, let’s capitalize on it.

A difficulty can be marrying ideas from different systems, in particular when juggling side effects or interferences between systems.

Say you want to use a supplement for your dog, take Apocaps (the one I use for my patients) for example.  How does this interact with conventional drugs or treatments? Well, for Apocaps there is an FAQ page on the website, but you don’t have the benefit of that for others.

Let’s look at “blood thinners”.  Many supplements and drugs may have a “blood thinning” effect.

What do we mean when the phrase “blood thinning” is used?

In actuality, this phrase is a horrible choice.  When we use the word “thinning”, it conjures up a concept called viscosity, which means how thick a liquid is.  High viscosity, very thick, like syrup.  Low viscosity, very “thin”, like water.

In actuality, “thin” blood is created by anemia or a low red blood cell count.  Anemic blood is very watery and dilute.

At any rate, what people are referring to when the phrase “blood thinners” is bandied about, is a left-over, archaic idea about humans prone to blood clotting who should take some aspirin to “thin” their blood.

I suppose this was meant to imply allowing blood flow without clotting.  (Honestly, blood clotting is  less frequent in companion animals compared to human patients.)

But really what is being referenced as “blood thinning” is low blood clotting, which is a totally different concept from anemia.

What’s all this about clotting anyway, and why do we care?  The reason our four-legged family members need adequate blood clotting is to stop bleeding.  This could be bleeding from a surgery or a tumor or from trauma or some other reason.

Low clotting, excessive blood loss.  This is why people (and the rare pet) on actual pharmaceutical blood “thinners” (anticoagulants) bruise easily- they bleed within their skin without adequate blood clotting.

Okay, so what does this mean for you and your dog?

There are some supplements and drugs that have some mild anticoagulant effects, or could in a small percentage of dogs.  You would want to keep these in mind if your dog is having an upcoming surgery.

And for all of you out there of the mindset “if it’s natural it has no side effects”, please tune in.

Here’s a little list of all-natural supplements that could have a little blood thinning effect:

  • fish oil
  • krill oil
  • omega-3 supplements
  • garlic supplements
  • curcumin or turmeric
  • maritime pine bark
  • Apocaps (the apoptogen supplement I created for my patients)
  • Bromelain
  • Wobenzyme-N
  • skullcap (scutellaria)
  • others

Not that there is a large risk of a problem here (more theoretical than anything), since the effects we are talking about are mild to none.  But to be safe, I advise my clients to hold off on these supplements a minimum of 3-5 days before surgery.

We see some similar effects possible, again at least theoretically, with anti-inflammatory drugs like Metacam, Rimadyl, Deramaxx, Etogesic, Previcox, Adequan, and others.

Now, having said that, the risk is so low that most vets will routinely use these meds postoperatively, but nonetheless, it would be wise to check with your vet before surgery if your dog is on drugs like these to see whether stopping them would be a wise choice before large surgeries with a lot of bleeding risk.

The other thing to keep in mind is that dogs with pre-existing bleeding disorders like low platelet counts, Von Willebrand’s disease or blood clotting factor deficiencies may be more at risk, since these dogs may be more prone to blood loss during surgery anyway.

I believe that every dog should have a nail or buccal mucosal bleeding test before surgery to make sure their clotting is in order.  These are easy, done under anesthesia (painless),  inexpensive, and take about 3-5 minutes.

If you would like to learn more about the top supplements in this arena, and how they interact with conventional veterinary care, get The Dog Cancer Survival Guide.


Dr D

In actuality,

Leave a Comment

  1. Margaret on July 17, 2020 at 3:12 pm

    Hi Dr. D,

    Is there anything we can do or feed to offset the mild effects of these supplements for dogs who have hemangioarcoma??

  2. Michelle Roniak on January 4, 2013 at 9:19 am

    Hi Dr D,

    Like Peter (above) I am also from South Africa and desperately looking for the Apocaps and K9 liver immunity and also am having trouble getting them through Amazon. Is there another way to get hold of them?


  3. Peter Long on September 8, 2012 at 12:15 am

    Dear Dr D

    I read some of the above blogs with interest.
    Please can you advise me: I have a German Sepherd of 7 years old who collapsed from a bleeding tumour (hemangiosarcoma) on 1 June 2012. Had his spleen removed. Tumour relatively small and no sign of spread. Vet very cautious in a positive prognosis. However I am in month 4 now and have a very healthy and happy dog. I have him on Salvestrol and other suppliments. My question is similar to one above : what is the chance that I may encourage another bleed by giving him daily 2,000mg fish oil / krill supplements; 1000mg milk thistle and 100mg daily of curcumin. I cannot get Apocaps or K-9 Immunity in South Africa, and Amazon will not send it here. Can I continue with this regime of supplements without the worry of another bleed (hopefully no tumours, but who knows ?).
    Would really appreciate your thought here.
    Much appreciated.
    Kind regards
    PS Have read your book and most inspired. Follow your diet with great success.

  4. DDmom on June 15, 2011 at 6:10 pm

    Dear Dr. D,
    My 10 yr old Dog has a confirmed tumor between the base of his heart and the right atrium. We have not confirmed that it is hemangiosarcoma because we do not want to put him through the surgery, but the vet’s best guess is that it is. After his first collapse and pericardiocenthesis, we switched him to your dog cancer diet (which he LOVES) and about 2 weeks later we started him on Apocaps. We were only doing 1/2 the dose of Apocaps, but his energy level noticeably increased. Unfortunately, he collapsed for a 2nd time and had another pericardiocenthesis. I ran across all this talk about “blood thinners”. With that said and his history of tumor bleeding into his pericardial sac, should I cut back on the fish oil, garlic and Apocaps?

  5. Hope on November 10, 2010 at 9:40 am

    Hello: My dog has Hemangiosarcoma. As this form of cancer can cause tumours to “bleed-out”, I am wondering if there is a risk in using supplements that may cause thinning of blood. My dog Tyson is a Lab and currently on Curcumin as well as a Vitamin-Mineral supplement that states that if you are on any co-agulant medication and taking this supplement, this may cause thinning of the blood. I asked my Holistic Vet if I should worry about giving this to my dog and she said that the Ginkgo (an ingredient in the supplement) may cause brain bleeding, but my dog is not on any co-agulants, so this should not be a problem.

    Her answer of “should not be a problem” does not sit well with me, so can I get your opinion on this matter?

    Thanks so much!


    • DemianDressler on November 23, 2010 at 6:47 pm

      Dear Hope-
      you make a good point. The question is really how close this cancer is to causing bleeding, which could be ascertained with an ultrasound most of the time. The blood thinning effects of the stuff your dog is on are not very strong however. You might like this blog too:
      I would also suggest that you use a more potent version of the supplements (Apocaps) of course with vet supervision, since it has not only curcumin but also a lot of other useful compounds.

  6. Megan on November 9, 2010 at 4:30 pm

    Dr. D,

    I have read all the info on the Apocaps website and it sounds great! It says, though, that it has not been studied in diabetic dogs. Do you have any personal experience with using apocaps in a diabetic dog? What could be the side effects for a diabetic dog taking this? My dog also takes a Ginger supplement twice daily with her meals. Do you recommend stopping the Ginger prior to starting the apocaps?
    Thanks for such a wonderful and informative blog!

    • DemianDressler on November 23, 2010 at 7:10 pm

      Dear Megan
      things like ginger and some of the stuff in apocaps have a conceivable lowering insulin requirement effect in diabetic humans. This has not been fleshed out in dogs. By the way Apocaps is loaded with gingerols, the polyphonols in ginger, so giving more ginger is a bit redundant. I think if you work with your vet and get some blood glucoses taken to be safe this would be a prudent approach to assessing your individual dogs response.
      Dr D

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