Is my dog's Doxycycline causing thirst, diarrhea, or low appetite?

Thank you for contacting Petco Pet Education Center, formerly Petcoach with your question about Cosmo. I'm sorry he has Lyme disease. The most common side effects of doxycycline HYC include vomiting, diarrhea, and a loss of appetite. More serious side effects include liver failure characterized by a yellowing of the skin, as well as seizures, bleeding, behavior changes, trouble swallowing, or an upset stomach when doxycycline has not been just given. Increased thirst is not a side effect of this medication, but some dogs with Lyme disease may develop kidney disease. One of the signs of kidney disease is increased thirst. I would not stop the medication, and I would give his vet a call immediately. It may be best you bring him into the vet immediately. Best of luck.

Thanks for using Petco Pet Education Center, formerly Petcoach. I’m so sorry to hear about Misty. If the medication had caused the vomiting, I would have expected it to cause vomiting days ago when you started it. That leads me to believe it is less likely related to the medication and more likely related to something else. That being said, double check that you are giving the correct amount and do shake the bottle well each time you give it. Just like in people, there are dozens of reasons vomiting occurs including: infection, dietary indiscretion (eating that piece of plant or human food, or dead mouse), GI foreign body (eating that hair band which is now causing problems), toxin, non specific nausea, diet change or new treat, and the list goes on. If it was just the three times in a row, I would just withhold food and water for 2 hours, then reinteoduce water. If she holds that down well, offer a small bit of food 8-12 hours after the last episode of vomiting. Don’t repeat tonight’s dose of medication. I am concerned in the back of my mind that something else is going on since her appetite had started decreasing. Is it related to the disease we are treating with the doxycycline or some other problem? Certainly if the vomiting continues or she is not ready to eat in the next 24 hours, or you see any new signs, please head to your vet or an emergency vet for re-valuation. Best wishes to you and Misty!

The extra dose probably caused the vomiting. Doxycycline does cause vomiting as a side effect. If the vomiting resolves, then I would not be concerned. If the vomiting persists, contact your veterinarian.

Poor Hildegarde! I would start by not feeding her for 12 hours and then reintroduce small amounts of plain boiled boneless, skinless chicken and white rice to see if this settles her tummy. You can also get her some probiotics to help firm her stool. I would not give her any doxycycline. This is not a typical antibiotic used for GI upset and it usually will cause more GI upset. If she continues to have diarrhea, I would have you vet look at her. I worry she is going to become dehydrated since she is so small. Your vet will be able to determine the cause and get her on the proper antibiotics. I hope this helps!

Hello and thank you for contacting Petco Pet Education Center, formerly Petcoach. Boss will be fine, there is no need to take him to the vet. Doxycycline is used in dogs fairly often. At the dose he ingested there should not be any side effects at all.

Hi there, thanks for using Petco Pet Education Center, formerly Petcoach. Diarrhea is not typically a symptom of tickborne disease so this is probably unrelated. Sometimes diarrhea can be a result of antibiotics, but usually it starts earlier in the course of treatment, so the timing doesn't seem related to that either. More likely she got into something that upset her tummy. As long as she's feeling fine, probiotics are a great idea, and you can feed a bland diet of boiled chicken with white rice for a few days. Once her stools improve, mix the rice/chicken mixture with her kibble to gradually switch her back. If the diarrhea doesn't improve over the next few days, and certainly if she starts acting sick (decreased appetite, vomiting, lethargy, etc), then a vet visit is in order. Hope this helps!

Yes in two hours the tablet should have been absorbed and dissolved already. This medication must be given with food and water as well as can cause oesophageal inflammation. I would suggest to wait until next dosage and I would suggest to withhold food for the next 8 hours and then start feeding with a bland diet based on boiled chicken and rice in small portion every 6 hours for the following 48hours. Then gradually reintroduce the normal diet over 5 days. I would definitively recommend a veterinary check up if the signs persist or you notice diarrhoea, more vomiting, lethargy or inappetence. Please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further.