As i tell everyone , 

Herding dog or not it is important to send  a message to the Veterinarian industry,

Do NOT use the drugs listed below, if they effect the MDR1 Gene they shouldn't be used at all

It is not only Herding breeds effected anymore 

and we need to be proactive in our allowed treatments of our Pets 

Both PARENT breeds to my understanding  MUST carry that gene in order to pass it to offspring.



Here is a Article i found, (sorry i cant recall where)


Herding Dogs with Resistance and Sensitivity to Pet Medications


In the past 20 years, many herding dogs have experienced side effects and reactions to certain medications due to the Multi Drug Resistant 1 (MDR1) gene, which can cause normal doses of drugs to have toxic effects. In addition, more than 30 potentially toxic drugs have been identified, and a lab test has been developed to identify dogs with the abnormal MDR1 gene.In addition, more than 30 potentially toxic drugs have been identified, and a lab test has been developed to identify dogs with the abnormal MDR1 gene.

We now recognize three different factors that contribute to drug toxicity especially common in herding dogs: a genetic mutation, drugs that inactivate normal cell pumps, and substances that inactivate cell enzymes so they cannot break down drugs.  The following sections explain how these factors cause drug toxicity:

  1. The cell pump (P-glycoprotein) and the MDR1 gene,
  2. The role of cell enzymes (CYP3A),
  3. Which herding-breed dogs have the MDR1 gene,
  4. Which drugs can become toxic if not pumped out byP-glycoprotein,
  5. Which drugs inactivate normal P-glycoprotein pumps,
  6. What happens when dogs with the MDR1 gene take drugs they should avoid, and
  7. How to have your dog tested.


  • Some herding dogs have a gene that causes drug sensitivity.
  • Laboratory tests can determine which dogs have drug sensitivities.

    What is the role of the P-glycoprotein pump and the Multi Drug Resistant 1 (MDR1) gene?


    Cells are like little cities and have methods of removing waste and toxic materials. One removal method is a protein pump that sits on the cell membrane and pumps materials out. This is called P-glycoprotein, which means it contains both sugars (glyco) and proteins. A gene codes for the P-glycoprotein pump, and some dogs inherit a healthy gene; others, a gene that has mutated. The mutated gene, the Multi Drug Resistant 1 (MDR1) gene, codes for a defective P-glycoprotein that cannot pump drugs from the cell. Thus, drugs accumulate and have a toxic effect even when given at normal doses.

    Dogs inherit genes from both their sire and dam so that they can have one defective gene or they can have two defective genes. Dogs with one defective gene (heterozygous for the defect) have less severe symptoms than dogs with two defective genes (homozygous for the defect). 


    What Role Do Cell Enzymes (CYP3A) Play?


    In addition to having proteins on the membrane that remove drugs from the cell, most cells have enzymes that break down drugs and inactivate them. Cytochrome P 450 (CYP 450) is a family of enzymes that inactivates about 60% of drugs used in pets. One of the CYP 450 family—CYP3A—can be blocked or inactivated by ketoconazole and by grapefruit juice. With CYP3A inactivated, drugs reach toxic concentrations within cells. 


    Dogs can have both the defective MDR1 gene and have inactivated CYP3A enzymes. These dogs are very likely to develop toxicity with certain drugs. 


    Which Herding-Breed Dogs Have the MDR1 Gene?


    • Australian Shepherd
    • Australian Shepherd Mini
    • Border Collie
    • Collie
    • English Shepherd
    • German Shepherd
    • McNab
    • Old English Sheepdog
    • Shetland Sheepdog
    • Mix breeds with any of the above

    Two sighthound breeds have the MDR1 gene:

    • Longhaired Whippet
    • Silken Windhound

    Which Drugs Become Toxic If Not Pumped Out by P-glycoproteins?


    Many different drugs are normally pumped from cells by P-glycoproteins: anticancer drugs, antiparasitics, antibiotics, cardiac drugs, immunosuppressants, opioids, steroid hormones, and miscellaneous drugs. The following is an alphabetical list of some of the drugs that can become toxic in dogs with the MDR1 mutation: 


    • Abamectin
    • Acepromazine
    • Actinomycin D
    • Aldosterone
    • Amitriptyline
    • Butorphanol
    • Cortisol
    • Cyclosporine
    • Dexamethasone
    • Digoxin
    • Diltiazem
    • Docetaxel
    • Domperidone
    • Ketoconazole
    • Doxorubicin
    • Doxycycline
    • Erythromycin
    • Etoposide
    • Itraconazole
    • Ivermectin
    • Levofloxacin
    • Loperamide
    • Methylprednisolone
    • Milbemycin
    • Morphine
    • Moxidectin
    • Ondansetron
    • Paclitaxel
    • Selamectin
    • Sparfloxacin
    • Tacrolimus
    • Talinolol
    • Terfendadine
    • Tetracycline
    • Vecuronium
    • Verapamil
    • Vinblastine
    • Vincristine

    Which Drugs Inactivate Normal P-glycoprotein Pumps?



    Some dogs have normal P-glycoprotein pumps (they don't have the MDR1 mutation), but their P-glycoprotein pumps are inactivated by certain antidepressants, antibiotics, cardiac drugs, immunosuppressants, opioids, and miscellaneous pharmaceuticals. When the pumps are inactivated, dogs experience toxic overdoses of drugs normally cleared by the pump. The following items inactivate normal P-glycoprotein pumps: 


    • Amiodarone
    • Bromocriptine
    • Carvedilol
    • Chlorpromazine
    • Cyclosporine
    • Erythromycin
    • Fluoxetine
    • Grapefruit juice
    • Itraconazole
    • Ketoconazole
    • Methadone
    • Nicardipine
    • Paroxetine
    • Pentazocine
    • Quinidine
    • Saint John's Wort
    • Tacrolimus
    • Tamoxifen
    • Verapamil

    Any dog—whether with normal P-glycoproteins or abnormal P-glycoproteins—is at risk for developing drug toxicity when taking the above items in conjunction with medications normally cleared by P-glycoproteins. 


    What Happens When Dogs with the MDR1 Gene Take Drugs They Should Avoid?



    The range of symptoms that dogs exhibit when they have the MDR1 gene mutation depends upon the nature of the drug they take. As examples, here are descriptions of symptoms caused by cancer drugs, ivermectin, digoxin, acepromazine, and opoids.

    Cancer drugs When dogs with cancer in organs that express the MDR1 gene (placenta, brain, kidneys, intestines, gallbladder, and testes) are given the anticancer drug doxorubicin, they have two problems. First, the doxorubicin has no effect on the cancer and the tumor is said to be chemotherapy resistant. Second, the dog develops severe diarrhea, bone marrow suppression, and loss of appetite.

    Ivermectin Ivermectin is an antiparasitic. It is used at low doses to kill heartworm microfilaria and at higher doses to treat mange. When herding dogs with MDR1 gene mutation are given Ivermectin to treat mange, they experience central nervous system (CNS) effects: cranial nerve abnormalities, coma, hyper salivation, dilated pupils, loss of balance (ataxia), and poor reflexes.

    Digoxin Digoxin is given to dogs with weak hearts, such as occurs with congestive heart failure. Herding dogs with MDR1 gene mutation develop anorexia, vomiting, and cardiotoxicity if given normal doses of digoxin.

    Acepromazine Acepromazine is given to calm dogs, but it puts dogs with MDR1 gene mutation into a stupor.

    Opoids Opoids (loperamide, butorphanol, and morphine) are given to stop diarrhea (loperamide) and to relieve pain (butorphanol and morphine). When these drugs are given to dogs with MDR1 gene mutation, they become stuporous.


    Common sense should tell you that if there are safer options , why not use them,, 

    It is important to instruct your Vet NOT to use the drugs that are on the MDR1 gene drug List 

    There are other safer options, that they are quite aware of and should be used in ALL breeds 

     Do not allow your vet to use any of these drugs on your dog 

    No matter what the breed. since more then just Herding dogs are becoming affected

    Better safe then sorry. Testing is not always reliable

    Australian Shepherds can have a severe reaction to Ivermectin, which is in many of the Heartworm medications on the market. So far, Interceptor was the only safe  Heartworm medication for Australian Shepherds, Collies, Border Collies, and other affected breeds. However the No longer sell it, so we have chosen to only use and recommend Natural heartworm prevention that can be purchased through Amber Technologies its called HWF.

    The MDR1 gene that causes this reaction must be carried by both parents in order to be passed on to their offspring. Since they have shut down the manufacturing of Interceptor..Update Interceptor is now available , but i dont trust it after all that happened,, 

     I now ONLY recommend Herbal treatments and preventatives (ask me), there is NO need to let them use your pet to "test" the new Heartworm products they are coming out with. Check out the Amber Technolgies HWF>Heartworm Free

    While Aussiedoodles are hybrids with Poodles, and therefore less likely to have the same issue as their parent breed, we recommend you take precautions against using any of the Heartworm medications containing Ivermectin.  or ANY drug on the MDR1 drug sensitivity list, since more then just herding breeds are being found to have this issue,PROTECT your pet,, 

    We are currently using a holistic approach to preventing and/or treating Heartworms-since the shut down of the Interceptor Heartworm Preventative manufacturer. This is working wonderfully for us, and several other breeders I know, and it is much safer for your Aussiedoodle. 

    Goto>>  Look for HWF>>.Heartworm FREE

    ,*Find a Store in your area or order online

    Since other breeds are  being effected by those drugs on the drug sensitivity list  & many other drugs on the MDR1 drug list,, an there are safer drugs available ,, why in the world would they still be using those drugs to begin with ,is always my question 

    Instruct your Veterinarian to NOT use any drugs on the Known drug list;;

    Those Drugs can cause serious injury or death,    

    IT IS THAT SIMPLE. If you insist on NOT using these drugs 

    then maybe, just maybe, they will figure out that a more natural approach is the better choice for all dogs. for both Heartworm Preventative and MDR1 issues, there are safer treatment drugs and ,,,in Fact THAT should be a Veterinarians First choice for ALL  don't you think?   

      ** i mean who benefits from any reactions?? Not You , Not your dog,,,,

    Recently it has come to my attention that the new Heartworm preventative Tryflexis has cause some severe and some Fatal reaction since it came on the market, Please research you other options below!!

    It is very important that you do not give Heartguard or Tryflexis to your doodle! 

    they should be well aware of the risk and be able to assist you with alternative options.for Heartworm Preventatives 



    AGAIN>>> It is important to instruct  your Vet NOT to use the drugs that are on the MDR1 gene List ,,it effects other breeds ,, ANY dog breed NOT just Herding dogs 

    There are other safer options that they are quite aware of 

     Do not allow your vet to use any of these drugs on your dog No matter what the breed. since more then just Herding dogs are becoming affected

    Better safe then sorry. Testing is not always reliable