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. Hi, my dog was given Temaril-P Monday, and his cough has changed but is still quite strong. Prior to this drug the vet had him on a breathing dilator, but it made him sound like there was a muffler in his throat.
    Therefore, I asked the doctor if she had any other ideas (he’s been diagnosed with bronchitis). Therefore, she gave me the Temaril-P twice a day, but his cough is still very bad.
    Would it be ok for me to give him some cough medicine to help with the cough. I have some creamulsions (sp) for adults.
    His vet is off today and can’t be reached…
    He is a Jack Russell 8 years old and 38lbs. (I know he’s over-weight) oh and he’s had heart worms, but they are all gone.
    The vet also said his heart is a bit enlarged most likely due to him being over-weight.
    Can you give me any advice to help his cough, it is scaring me to death.
    Thanks in advance for your help,

  2. I have 2 shar pei that have been prescribed Antirobe for skin issues and I am wanting to give Advantage II for their monthly flea application. Are there any interractions with the two of these meds? I am so leary about flea medications.

  3. Can Clindamycin and Advantage II be given together without any problems or drug interractions?

  4. Dr. Michael Dym, VMD veterinarianMay 1, 2014 at 9:45 pm

    I don’t see a problem with both of these

  5. Dr. Michael Dym, VMD veterinarianMay 1, 2014 at 9:47 pm

    yes they can be used together

  6. Dr. Michael Dym, VMD veterinarianMay 1, 2014 at 9:50 pm

    You can try children’s mucinex cough medicine at dose of 2 teaspoons 3 to 4 times daily until vet recheck.

  7. my 11 yr old peke-a=poo is on theophylline 50mg 2x daily and temaril-P 1 tab daily. Can theophylline be taken without the temaril=P as I worry about the long term side effects of this medication.

  8. Dr. Michael Dym, VMD veterinarianMay 3, 2014 at 5:32 pm

    It is ok to use the theophylline with the temaril p

  9. I have my shar pei on clindamicin and gave her Advantage II for her flea meds 2 days ago. Is it okay to her Heartguard with that since she is due for her heartworm or wait a bit?

  10. Dr. Michael Dym, VMD veterinarianMay 4, 2014 at 2:29 pm

    I would wait 2 weeks, as shar peis are very sensitive to chemicals and too many toxins or pesticides given too close together.

  11. Hi Dr. Dym,
    Thanks so much for your help, and I will try the cough medicine. His cough has gotten better, but he does still have strong coughs at times.
    He’s been reduced to one tablet a day now, and the vet told me to try and finish this med before trying to bring him bank in.
    Thanks again for your advice,

  12. Is it okay to give a cat a flea treatment that contains Piperonyl Butoxide??

  13. Is it ok to give a 50lb dog with hives and swelling prednisone and benadryl at the same time? We found her with hives and itching last night and gave her one 25mg benadryl. Vet said to give her 20mg of prednisone at 10am this morning, now it’s 10pm and the hives are back. do we do another 15mg of prednisone? Can we give her a benadryl too?

  14. Is it okay for my Chihuahua Minpin mix to take Zeniquin, Medrol and Fluconazole at the same time? She has severe allergies and we have trying to clear it up. This is the most recent mix of prescriptions. She has been taking the Zeniquin and Medrol for two weeks with no problems, I am just concerned about adding another medicine to the mix. She is also using a Chlorhexidine Climbazole mousse 1x daily on the irritated area. I have been unable to find any information about interactions online.

  15. vet said my dog has AFIB ..
    MY DOG IS ON GIDOXIN and diltiazem along with lasix. i feel asleep one night and forgot to give him his night time does. i always been waking up checking on him sense he has been on the meds, i have notice he was feeling better every time i woke up he seems to be feeling better. u think maybe the digox and diltiazem is to strong. while taking these meds he seem to be going down hill more and more each day…

  16. my 20 lb dog is taking:
    rimadyl 25 mg (1 tablet once a day),
    tramadol 50 mg (2 tablets twice a day),
    cefpododoxime 100 mg (1 tablet once a day),
    lactulose (2.5 mls every 8-12 hrs)

    Could there be a bad interaction with these drugs?

    She is acting strangely. Shallow breathing. Sudden movements – bolting up from sleeping and staring into space.

    We took her in originally for bad constipation, and an abscessed anal gland. She is still swollen and red 3 days later.

  17. I’m surprised that drug interactions are never discussed when medications are given to our pets. It’s frustrating to the client that finds themselves with questions on a Saturday morning.

    My little dog recently had surgery on both of her knees, and I’m trying to find out if there will be any negative interactions with Tramadol and Iverhart Max. Half of her body is now shaved, and in Florida, mosquitoes are always an issue anyway.

    As I sit here looking at the box, I also noticed that she was given 12.1-25 lbs, and she currently (last Tuesday) weighed exactly 11.0 lbs at the surgeon’s office. Can I break these tablets in half, or is the medication not evenly distributed throughout?

    Thank you!

  18. Dr. Michael Dym, VMD veterinarianMay 11, 2014 at 9:09 pm

    Stick with the higher dose of iverhart, which is very safe. Tramadol and iverhart no problem in my experience. Also consider working with holistic vet on improving health. To learn more about holistic medicine, go to my website http://www.doctordym.com Many homeopathic vets do offer phone consultations.

  19. Dr. Michael Dym, VMD veterinarianMay 11, 2014 at 9:10 pm

    Alot of drugs to be on in my opinion at once. Tramadol is HUGE dose for this size dog. I would cut dose in half and call your vet about why such a high dose.

  20. Dr. Michael Dym, VMD veterinarianMay 11, 2014 at 9:13 pm

    I would recommend consulting with a veterinary cardiologist in your area, who can help guide drug therapy for AFIB. These drugs are appropriate, but now a days, digoxin is not used much anymore by many, as safer alternatives, including dlitiazem, and others, as well as Vetmedin, beta blockers, etc

  21. Dr. Michael Dym, VMD veterinarianMay 11, 2014 at 9:22 pm

    HI Kelly. I don’t think there is any specific reaction to worry about here, but with any anti fungal drugs, diarrhea, vomiting or loss of appetite can be seen, even with the safer fluconazole.

  22. Dr. Michael Dym, VMD veterinarianMay 11, 2014 at 9:24 pm

    Pred and benadryl fine to use at same time during acute allergic reactions or hives, etc

  23. Dr. Michael Dym, VMD veterinarianMay 11, 2014 at 9:25 pm

    I prefer not to use this type of product due to increase risk of reactions and side effects

  24. Dr. Michael Dym, VMD veterinarianMay 11, 2014 at 9:27 pm

    You are very welcome Ron

  25. Can I give Rymadal, adequan and benedryl together. I have a 15 lb 17year old Jack Russell.

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