Why you need to ask your vet about pet drug interactions & side effects

Discuss potential medication side effects with your vet

In the middle of a busy veterinary practice, many veterinarians may overlook an opportunity to discuss the possibilities of drug interactions and pet medication side effects. For example, many commonly prescribed nonsteroidal anti-inflammatory medications (NSAIDs) can sometimes cause digestive upset and/or liver/kidney problems in some sensitive pets. Corticosteroids like Prednisone can cause similar problems in some pets, as well as predispose pets to diabetes with prolonged use.

While a topic of debate, these risks are increased if Prednisone and nonsteroidal anti-inflammatory drugs are used together.

While potentially lifesaving, antibiotics can also cause allergic reactions from digestive upset to skin irritation. Some pets are sensitive to topical flea and tick medications, and in my practice I always administer topical flea and tick medication on a separate day from heartworm preventative medication or vaccinations, in order to lessen the burden on a pet’s immune system.

Whenever multiple drugs are prescribed it is always important for pet owners to ask questions, because veterinarians not only prescribe pet medication but are also dispensing these medications in private practice.

Have pet health questions? For any medical concerns, we always recommend you consult your veterinarian. However, for non-emergency questions, you can contact Dr. Dym directly using our Ask the Vet form.

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  1. Our recently adopted Husky is having hard time with allergies. He also takes low dose Xanax and Prozac for severe separation anxiety. Would it be okay to add beadryl to help him with his itching? He shows no sedation from his other meds but, we don’t want him to be hurt if we added anything else.

  2. Our recently adopted Husky is having hard time with allergies. He also takes low dose Xanax and Prozac for severe separation anxiety. Would it be okay to add bendryl to help him with his itching? He shows no sedation from his other meds but, we don’t want him to be hurt if we added anything else.

  3. I have a 14 yr old greyhound on meclizine hyrdochloride to help with equilibrium issues. She is now having difficulty getting up and and laying down (looks like she is uncomfortable). I’d like to see if an NSAID will help. Can I give Previcox?

  4. Dr. Michael Dym, VMD veterinarianApril 15, 2014 at 11:06 pm

    I don’t see a problem using an NSAId like previcox with mecliizine, but best to check with your local vet who knows dog well, as well as who can do blood work before going on previcox

  5. Dr. Michael Dym, VMD veterinarianApril 15, 2014 at 11:10 pm

    Low dose benadryl should be no problem with these, but check with your local vet as well.

  6. Dr. Michael Dym, VMD veterinarianApril 15, 2014 at 11:18 pm

    It can be taken with phenobarbitol, as long as liver enzymes are ok which can be checked at the vet. Also consider homeopet natural product for incontinence from 1800petmeds.

  7. Dr. Michael Dym, VMD veterinarianApril 15, 2014 at 11:22 pm

    No generic piroxicam that I know of but I would check with your local pharmacist.

  8. Dr. Michael Dym, VMD veterinarianApril 15, 2014 at 11:34 pm

    You could look into natural heartworm preventative and therapies such as black walnut or quassia bark from http://www.fiestapetdeli.com Also you should see book Vital Dogs don’t get heartworm by Will Falconer, DVM which you can get on line for more tips. Slow kill with monthly heartworm is option, but most cardiologists feel that young dogs this age should be treated with injectable arsenic adulticides. I am not familiar with slow kill you ask about, as well as cephalexin is not adequate in heartworm positive dogs as it does not kill the accompanying Wobachia parasite as does doxycycline

  9. My 10 year old 64 pound lab has been prescribed 150 mg of doxycycline 2 times a day for ehrlichia. She also takes 25 mg of Proin twice a day for incontinence. Can these two drugs be
    taken together?

  10. Dr. Michael Dym, VMD veterinarianApril 17, 2014 at 11:36 pm

    Yes I don’t see a problem with these two drugs

  11. Hi, I have a 16 lb shih tzu who has been on 5 mg of Prozac for a year for anxiety. When his anxiety level gets too high, we also have a prescription for him for .25-.5 alprazolam. He was recently put on daily denamarin for elevated liver levels. He was rechecked after 5 days and his blood work improved immensely! My vet said we could increase his Prozac (fluoxetine) to 10 mg if needed due to a sudden increase in anxiety. Seems like this happens in early spring which seems odd. He’s afraid of storms and loud sudden noises but we haven’t had either recently. Happy as a clam during the winter and even decreased his Prozac for the fall/winter season. Are these meds safe together and is 10mg a safe amount for his weight? I’m hoping to cut out the alprazolam ASAP . Thanks for your time! Lisa

  12. One week ago I adopted a 6-year-old German Short-Hared Pointer from no-kill shelter. He is being given Clavamox 250 mg bid and Albon 250 mg 2.5 tabs bid. He seems to have rather soft stools and he has the “heaves.” Some are productive (with a white substance) while most are non-productive. Would giving him famotidine or famotidine AC have ANY potential for drud-drug interactions? Appreciatively,

  13. I have my 11 lbs pom on phenobarbital and now she is having congestive heart failure and my vet put her on vetmeden and enalapril in the past we tried to change her phenobarb for another seizure medication and she had a reaction to it dropping her platelets dangeruosly low..now with the above medications I see brusing on her stomach. would this be a reaction to the drugs? could they be dropping her platelets low again?

  14. Dr. Michael Dym, VMD veterinarianApril 20, 2014 at 5:05 pm

    I have not seen vetmedin or enalopril cause platelet abnormalities but based on what you are seeing you need a vet recheck ASAP and have CBC/blood work checked.

  15. Dr. Michael Dym, VMD veterinarianApril 20, 2014 at 5:10 pm

    Giving famotidine would be fine, however he may have kennel cough, and need better meds for that such as doxycycline or baytril.

  16. Dr. Michael Dym, VMD veterinarianApril 20, 2014 at 5:13 pm

    I don’t think the higher dose of prozac will be a problem with the alprazolam Strange how you saw sudden increase in anxiety. Curious if dog received any recent vaccinations, especially rabies vaccination, which I have seen sometimes cause abrupt increase in anxiety, etc in sensitive dogs. As for other options, consider natural amino acid like L-theonine at dose of 100-200 mg twice daily which is wonderful natural anti anxiety supplement for both people and animals. Also can consider flower essence called Be serene from 1800petmeds which also may help. Consider working with a homeopathic vet. To learn more about homeopathy, see ww.doctordym.com Many homeopathic vets do offer phone consultations.

  17. Michelle, I am sorry for interruption, but those red spots on the stomach is AIHA, immune problem. Go to Facebook and type Optimum Choices https://www.facebook.com/FreedomFromIllness or http://www.optimumchoices.com/
    I saved my dog she had red spots on her stomach, I took her to vet, she had low blood count, prednisone and azathioprine were not helping, just read what people write on Facebook about bio preparation F3+. Also ask your vet to do blood test for mycoplasma, tick test, that could be the reason then they will most likely prescribe doxycycline antibiotic. But the only thing can help is algae by optimum choices, they have like 100 testimonies on Facebook, don’t waste your time

  18. Thank you for that valuable information.

    What are the potential dangers of kennel cough to my ndew buddy?

    Is there any “danger” to humans as the result of kennel cough?

    Dave W

  19. My 65-lb black lab has copper retention in her liver and has been treated for this since July 2013 with very good results. Am concerned about giving her Trifexis….She takes Penicillamine, Vitamins E, Sam-E, Milk Thistle, and B-6. Any problems mixing these? Thank you.

  20. how much flee med does a cat need in. If you buy dog med for a dog. it comes in a 2.25kg. the cat weighs 8 lbs?

  21. Dr. Michael Dym, VMD veterinarianApril 26, 2014 at 3:46 pm

    I don’t recommend splitting dog dose….Only use approved labelled drugs for cats

  22. Dr. Michael Dym, VMD veterinarianApril 26, 2014 at 3:59 pm

    No problem in humans with kennel cough from dogs. Kennel cough usually resolves on its own or with antibiotics over 10-14 days.

  23. I did wish to place a ‘period’ at the end of this string. My precious, adopted, 6-year-old German Short-haired Pointer, who I had for only a scant 7 days, spent the subsequent 6 days in a vet’s care and then in an imoressive Veterinary Hospital

    “Cooking Dough’ was euthanized today as a result of overwhelming bilateral pneumonia, pleural effusion, kennel cough, and extreme dehydration. I am devastated, though I am certain that I chose what was best for this precious pup.
    In my humble opinion, may I offer to you that ‘Quality of Life’ exceeds the numbers of years that someone lives.

    To those out there reading this string, I implore you to choose a ‘reputable’ vet after an adoption to be sure that he/she is given the complete ‘once-over’. Quite clearly, the vet (in an office of 8 vets) that saw my baby is overwhelmingly incompetent to be seeing animals of any species.

    Please read on, as I wish to provide you with a complete, balanced story of my experience. Eight years ago, we brought our 12-year-old beagle to the vet for what appeared to be a rather small skin issue. The incompetent vet that I am referring to Dx’d the problem as a rather insignificant, bacterial skin infection. In fact, it was a metastatic cancer that was manifesting itself on his skin. In all fairness, my little beagle boy would probably have succumbed to the cancer no matter the Dx of the skin issue.

    Now, a mere 8 years later, although I thought ‘Cookie Dough’ was going to be seen by the owner of the vet hospital, it was she who performed the most cursory of examinations. I take full responsibility for not insisting on other tests to be run. She did not draw any blood. All that was tested was the stool sample I had brought to the appointment. She performed a limb range-of-motion exam, an auscultation, and looked at his teeth. From the sample, it was discovered that C.D. had coccidia, and we were sent home with Albon.

    The very next day, with C.D. showing signs of severe distress, I called that vet hospital’s emergency phone number. Guess who was on the other end of the phone? Yes, it was her! With her TV blaring in the background, she clearly delivered a bull-stool response. In fact, she was clearly pissed off that I had contacted this very Web site in order to do my own research.

    Now, I find it 100% impossible to believe that over an 8-year span, my 2 dogs were the ONLY 2 animals to have been ‘mal-diagnosed’ by this vet. IMPOSSIBLE statistically soeaking!

    Therefore, I’ve completed and mailed a form, provided by my state’s Department od State, to have her vet license revoked, or at a minimum not to allow this vet to care for live animals as we go forward.

    Lastly, what does it tell you that when I placed a matter-of-fact, friendly call to advise this vet’s office manager of C.D.’s condition, that she plainly and politely said she couldn’t say anything on the advice of counsel and their insurance carrier. Does this suggest to anyone that even their own practice believes she has done wrong? Or, are the simply taking precautionary measure?

    In my eyes, this is a no-brainer.

    Please feel free to share with me any thoughts you (anyone) may have. But please make the discourse civil. Please.

  24. can my dog take Prednisone 5 mg and apoquel at the same time together they control her cough and allergies

  25. Dr. Michael Dym, VMD veterinarianApril 28, 2014 at 2:45 pm

    yes no problem using both at same time

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