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. Dr. Michael Dym, VMD veterinarianMarch 6, 2014 at 12:19 am

    Given all of the vast lesions that you describe, I would strongly recommend vet recheck and have needle aspirate or biopsy of the raised warty lesions.

  2. Dr. Michael Dym, VMD veterinarianMarch 6, 2014 at 12:24 am

    If your vet prescribed the meds, I would follow his or her instructions. Perhaps consider working with a holistic vet on trying to improve his overall health To learn more go to http://www.doctordym.com

  3. Dr. Michael Dym, VMD veterinarianMarch 6, 2014 at 12:25 am

    Ask about pain drug called amantadine. Also consider supplement Dev Cor Mobility by Vetri science, as well as Yucca intensive from 1800petmeds.

  4. Thank you for answering so quickly! I will make an appointment for Pipper ASAP. Do you think it is safe for me to be giving her the Temaril-P, which to my understanding is Prednisone, Meloxicam and Tramadol together? That makes me a little nervous after reading some of the posts, I certainly don’t want to make my dog worse instead of better! Tramadol 50 mg 2 b.i.d., Temaril
    3 q other day and Meloxicam 7.5 1/2 qd.

  5. Dr. Michael Dym, VMD veterinarianMarch 8, 2014 at 12:57 am

    I would not use temaril P and meloxicam at the same time as increased risk of GI ulceration and digestive upset.

  6. I have a 77#, 9 year old golden retriever who is on pheno for seizures and thyroxin for thyroid issues. He hasn’t had a seizure for a while, and his skin issues have been so much better with the thyroxin. However, I just took him to the vet for a large hot spot between his ears, and the vet gave him Rilexine 600mg/2x daily. He also had an injection at the office (may have been prednizone, but I can’t locate my paperwork at this moment.) The vet also put a typical ointment on his hot spot. He had a small seizure tonight. Could this have been an interaction with any of these drugs?

    After reading some of the Q/As here, I realize there may be a reason to be careful of vaccinations for my dog?

  7. I have a 10lb shih Tzu that had ingested about 10mg of frontline liquid. What should I do ?

  8. Dr. Michael Dym, VMD veterinarianMarch 9, 2014 at 11:40 pm

    If caught within a few hours, best to induce vomiting at vet with ipecac or possibly using hydrogen peroxide orally,

  9. Dr. Michael Dym, VMD veterinarianMarch 9, 2014 at 11:45 pm

    Definitely would NOT vaccinate a dog like this given seizure and thyroid issues. As for drug interactions, I dont think those involved in recent seizure.

  10. Is it o.k. to give rimadyl (75 mg.) , zeniquin (25 mg.) and hydroxyzine (10 mg.) together?
    Our 14 yr. old cockapoo (18lbs.) was diagnosed with a nasal tumor, and has nasal congestion and bloody discharge from her nose. Also, we had been giving her benadryl prior to this diagnosis. Should we also continue the benadryl? She struggles to breathe through her nose more at night, but it is also getting worse during the day.

  11. Doctor,
    My chow mix has always been a nervous boy with bad hips. He has been on reconcile before but he is not on it now. For the last two years I have had him on the lowest possible dose of rimadyl for him to be comfortable with his hips. Recently, the vet has put him on trifexis instead of frontline plus. With this long winter and very little outside exercise, he has been crawling out of his skin and gets so worked up nervous wise that he pants and licks almost constantly. When this happens he vomits and gets bloody diarehea. It’s hemoraghic something or other. Well, I’d like to put him back on reconcile to help his nerves – the vet has said that it will be ok to. Can you confirm there will not be a problem drug interaction-wise with him being on reconcile, rimadyl, and trifexis? Thank you!!!

  12. Dr. Michael Dym, VMD veterinarianMarch 12, 2014 at 1:01 am

    In most pets, this combination should not be a problem, however in many sensitive dogs with behavior issues, there are possible mental, emotional or neurologic risks with any of these drugs.

  13. Dr. Michael Dym, VMD veterinarianMarch 12, 2014 at 1:04 am

    This combination should be ok in most dogs, however not worthwhile to use both benadryl and hydroxyzine at same time

  14. Hi-

    I have an 8 year old, 110 lb lab. Is it OK to give him fluconazole and prednisone together?

  15. Dr. Michael Dym, VMD veterinarianMarch 12, 2014 at 8:28 pm

    I dont see a problem with these two, but he should be under care of local veterinarian.

  16. My 13 yr. old cat was recently given depo medrol (needlessly) and ended up with heart enlargement and fluid in his lungs. As a result, he was prescribed lasix, enalapril and Plavix but I can only manage to give him the lasix and some of the enalapril. The Plavix has such a vile chemical odor that he won’t come near it. I had read that a baby aspirin every 72 hours could be used instead of Plavix (I also read that it should not be coated aspirin), and that doses as low as 5 to 20.5 mg. aspirin worked just as well. Either way, my vet is insisting on Plavix. Can you offer any insight ? Also, after 6 days on lasix, his respiration rate is normal. X-rays taken before starting the medication showed an enlarged heart, a problem with the blood vessels at the bottom of the heart on both sides, and fluid in the lungs, but now the heart is normal sized, sits properly, blood vessels on the left side are normal, the ones on the right side are improved quite a bit, and the lungs are clear. Is it possible for things to resolve so that I won’t be medicating him for the rest of his life.

  17. my almost 10 year old chihuahua has been kinda slow to go down the steps lately and last night he started favoring his back hips…like slow to lay down and get up…and he’s been pacing a bit before finally laying down..and really doesn’t want anyone around him or to pick him up when we have to bring him outside….thinking it might be arthritis….I bought him some joint health support today..but was wondering if I could give him anything else over the counter to help with the pain he’s in?..or if I should be more concerned?…because he’s really just laying there hasn’t even eaten much today..he’s also on phenobarb

  18. What happens when a dog takes prednisone and novox together ? The vet my dog seen overlooked that he was taking novox when she prescribed prednisone for blood in his ear flap.

  19. Dr. Michael Dym, VMD veterinarianMarch 17, 2014 at 6:06 pm

    These drugs should not be used together because of increased risk of GI ulceration, bleeding and vomit/diarrhea.

  20. Dr. Michael Dym, VMD veterinarianMarch 17, 2014 at 6:10 pm

    I Would have vet exam and evaluation in pet this age to see if arthritis and/or other senior diseases may be present in dog this age. I would try natural remedies like yucca intensive and proanthozone from 1800petmeds. Dog gone pain is another good one you can find on line, but I would certainly recommend a vet check.

  21. Dr. Michael Dym, VMD veterinarianMarch 17, 2014 at 6:19 pm

    It is possible for things go slowly resolve, if triggered by cortisone shot. Only a vet cardiologist is qualified to tell you that, and only after a thorough echocardiogram is done to look at the structures of the heart. As for plavix, for YEARS I used low dose aspirin every 3 days without a problem, and my career spans 23 plus years. Perhaps consider second opinion, from different vet who may support aspirin use in lieu of plavix.

  22. Can Heartguard and Vitamin K capsules be administer together? also my dof is due on the Frontline this week.

  23. Can Heartguard and vitamin K capsules be administered toghether? also my dof is due on the Frontline this week.

  24. Dr. Michael Dym, VMD veterinarianMarch 20, 2014 at 9:13 pm

    I dont see a problem giving these together

  25. I took my dog to the vet due to hair loss. Turns out she is allergic to fleas. She has a skin infection. They gave me comfortis and ciprofloxacin. Can I give these to her at once?

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