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My dog has hives after antibiotics. Is it an allergic reaction?

Updated on September 23rd, 2025

Pet's info: Dog | Pit Bull Terrier | Female | spayed | 73 lbs

My moms pitbull just finished a course of antibiotics which was cephalexin. Today was her 7th day and she has now broke out with horrible hives all over her body!

1 Answer

Most Helpful Answer

Answered By Shaneez Wallani, DVM

Veterinarian

Published on January 17th, 2019

Poor Gia! Please call a vet near you immediately to have her seen to help treat the hives. Since she's had 7 days worth of medication and the hives only appeared today it is not very likely that they were caused by the antibiotics, but I recommend telling your vet about them just in case. Gia may have ingested something she is allergic to or have been bitten/stung by something she is allergic to, and your vet can help direct treatment to prevent spreading of the hives and worsening of her symptoms. If you notice any difficulty breathing that is an emergency situation, as it could indicate a severe allergic reaction, and requires immediate vet care. Good luck and I hope she feels better soon!

1Pet Parents found this answer helpful

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