Guinea Lynx A Medical and Care Guide for Guinea Pigs


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Some Medications are Deadly to Guinea Pigs

While all antibiotics will affect the gut flora of a guinea pig, some are deadly and can cause a fatal enterotoxemia.

All penicillin based drugs are toxic to pigs!

Amoxicillin (Clavamox) is one that is frequently and mistakenly prescribed by unknowledgeable vets.

Ensure your pig is not prescribed any penicillin based drugs. A vet experienced in treating guinea pigs should never prescribe any of these medicines and should be able to provide you with a more complete list of toxic medications or find that information. If not, find another vet.

A guinea pig given any of the following medications orally may require medical intervention.

Medications to Avoid! This list includes some of the most deadly antibiotics. Derivatives of these drugs may also cause problems. Using drugs like amoxicillin can make a bad situation worse so it is best to avoid them completely. Avoid these medications and their derivatives:
  • amoxicillin (Clavamox)
  • ampicillin
  • bacitracin
  • cefadroxil
  • cephalexin * (derivative: Cefadroxil)
  • cephalosporins
  • cephazolin
  • chlortetracycline
  • clindamycin
  • dihydrostreptomycin
  • erythromycin
  • lincomycin
  • oxytetracycline
  • penicillin
  • streptomycin

Rabbits have a similar digestive system. The chart at the bottom of this page describes the dangers associated with using many of these same medications. Keep in mind this is a list for rabbits. Never give guinea pigs penicillin in any form by any route.

Some medications should never be prescribed, some can be given by injection but never orally. If there are better alternatives, do not risk use of an injected antibiotic but use a safer one. Other medications may be tolerated only topically (apply very sparingly -- if the animal ingests the medication, diarrhea and enterotoxemia may result). Eye medications are considered topical and are generally safe so long as they are not ingested.

Sources/References Information regarding safe medications can be obtained from the following reference books, which also list the above medications as dangerous to guinea pigs. Do not add any medications to your guinea pig's drinking water. Dose your guinea pigs individually to ensure they receive the correct amount of any medication.

  • The Biology and Medicine of Rabbits and Rodents by J.Harkness DVM and J.Wagner DVM (Williams & Wilkins - a Lea and Febiger Book)
  • Diseases of Domestic Guinea Pigs by V.C.G. Richardson (Blackwell Science Ltd.)
  • The Exotic Animal Formulary by James W. Carpenter, MS, DMV et al (W.B. Saunders Company)
  • Ferrets, Rabbits and Rodents - Clinical Medicine and Surgery by E.Hillyer DVM and K.Quesenberry DVM (W.B. Saunders Company)

* Regarding cephalexin--mentioned above--(derivative: cefadroxil), a pet owner at CaviesGalore reported her guinea pig had a serious reaction to this drug, eventually resulting in its death. Other sources claim it is very harsh on guinea pigs. Do not administer this drug orally. Because there are so many other safe and effective medications, cephalexin is best avoided. PRINTABLE PDF: Dangerous Medications Go Up

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