Where People & Piggies Thrive

Newbie or Guinea Guru? Popcorn in!

Register for free to enjoy the full benefits.
Find out more about the NEW, drastically improved site and forum!

  • ONE THREAD per pig please!
    We really want your pig's history all in one place to help you. Please don't start a new thread for a new issue. Just reply to your old one. We can edit the title for you if needed.

Vet Expired Antibiotics


Well-known Member
Cavy Slave
Sep 1, 2011
So I am kinda worried about our littlest, Mushu. We have been treating his URI for over a month, and the symptoms are improving, but if we stop medicating him for a couple days, they flair back up. I plan on consulting the vet in the next day or two.

Mushu is still eating, drinking and running around the cage with Havok a few times a day, so he seems to be alright besides being a bit lethargic. However, i realized today the Trimethoprim Sulfa that we were prescribed to give him expired 3 weeks ago! I know expired antibiotics can be harmful. Have we cause Mushu irreparable harm???
I doubt you've caused him irreparable harm, but he may not be getting the treatment he needs.

Medicines don't have a specific hour or day when they quit working -- they just taper off in effectiveness after a certain point. Some taper more quickly, while others are good for a long time. Expiration dates are estimates about how long the medication is effective, and are driven partly by concern for liability if the drug doesn't work. They rarely, if ever, become toxic as they decompose.

However, if he hasn't improved in a month of antibiotics, it's time to try something else. I'd go back to the vet with him.
I know you problem is that expiration date has passed, but the reason he may still be having issues with the URI is you mention you take him off his meds for a few days if he seems fine?
I don't want to sound mean here but the thing with antibiotics is you simply can NOT take them off for a few days then put him back on, you have to stick to the full treatment with no off days unless it says otherwise. The reason being is that constantly putting him on and off antibiotics in a short time will cause the bacteria to build up and immunity to the drug and become a stronger bacteria and make it very difficult to get rid of. I would defiantly see a vet soon.
This thread has been closed due to inactivity. You can create a new thread to discuss this topic.

Similar threads

URI/Upper Respiratory Infection Antibiotic Question
Guinea Pig Papa
Guinea Pig Papa