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Updated: Sep 1, 2022

Did you know that the list of ingredients for most vaccines is proprietary information – which means vaccine companies are not required to disclose their ingredients to the consumer. Even if your pet has a reaction to a vaccine, the company is not required to divulge the ingredients of the vaccine.

Crazy right?

The majority of rabies vaccines contain mercury. It goes by different names: Thimerosal, Thiomersal, Merthiolate, and others. Merthiolate tincture, used by our parents (or grandparents), was used as a topical disinfectant or antibacterial for wounds, scrapes, and cuts. In the late 1990s, Merthiolate and Mercurochrome were removed from the market in the US because they contained mercury. Mercury can be dangerous – it is a poison.

What is thimerosal?

Thimerosal is a mercury-based preservative which is nearly 50% mercury by weight. Thimerosal was first introduced in vaccines by Eli Lilly in the 1930s. Thimerosal is a very inflammatory neurotoxin and genetic mutator and Pittman Moore Animal Pharmaceutical Company warned against its safety “even in dog serum” to Eli Lilly Company in 1935. Pittman Moore found that over 50% of vaccinated dogs suffered inflammatory reactions to Thimerosal.

These safety issues were raised in Congressional testimony several times and the correspondence from Pittman Moore to Eli Lilly is a part of Congressional Hearings testimony on the dangers of mercury in vaccines. Despite this, Thimerosal is still used as a preservative in a staggering number of vaccinations for both humans and dogs.

Symptoms of Mercury Poisoning

People who are exposed to mercury at levels above limits set by federal agencies such as the FDA and the EPA run the risk of mercury poisoning. Symptoms of mercury poisoning include:

  • Nausea

  • Vomiting

  • Fatigue

  • Difficulty walking or speaking

  • Tremors

  • Attention deficit

  • Brain, lung, or kidney damage

  • Coma

Thimerosal has been banned from children’s vaccines in several countries including Russia, Denmark, Great Britain, Austria and Japan. But in the US, we are still using it. Do you know why? So pharmaceutical manufacturers can save a few pennies by using multi-dose vials instead of the preferred “single use” vaccine vial. Most inexpensive veterinary rabies vaccines contain thimerosal as a preservative so manufacturers can bottle them in “multi-use vials.” Our kids and pets are the ones paying the consequences. Isn't that great?!

What we can do?

1. Ask your vet for thimerosal mercury-free rabies vaccine. Sadly, most veterinarians are not going to inform us about this vaccine, so you have to ask for it.

2. It is important that we do our research first, there is tons of information online and we need to ask a lot of questions to our veterinarians about pet vaccines. If they don't give you an answer, or don't know about this subject, maybe it is time to switch vets.

3. Don't let your vet over-vaccinate your fur kid. To reduce the effects of vaccinosis (excessive vaccination), researchers involved with the Rabies Challenge Fund have demonstrated a minimum of 5 years of immunity to rabies after vaccination.

Until federal law accepts longer duration of immunity for rabies vaccines, pet owners and veterinarians should use mercury-free vaccines.

4. Ask your vet for a vaccine titer (blood test) before your fur kid gets a distemper-parvo vaccine. This is to prevent them from being over-vaccinated.

5. Do you know that Bordetella vaccine should only be given to your dog if boarding/grooming places require it? Most vets don't give this info, so it's better that we become informed and ask.

Sadly some vets only care about making profit and don't care about our loyal companion. But I know there are great vets too, like my dog's holistic veterinarian. This vet carries thimerosal (mercury)-free rabies vaccines and homeopathic detox medications for the rabies vaccine. (Ask your vet for this too)

We love our fur kids and we want them to have healthy lives, so it's important to ask as many questions as possible. We shouldn't be afraid to ask our vets all our questions and voice our concerns. Follow your intuition. Ask for second opinions too. Our pets' lives are in their hands.

* The information on this blog is not intended to replace a one-on-one relationship with a qualified healthcare professional. If you have questions or concerns about your pet's health, please talk with your vet.

*As a designer and a dog mom, I created an apparel and home collection for pet parents like you. And part of the proceeds will go to rescue organizations. Check it out!

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