This group of antibiotics on the whole are very safe.
+
+
* It has been known to cause acute anaphylaxis or mild hypersensitive reactions.
+
* High intravenous doses can lead to platelet dysfunction.
+
* Penicillins containing procaine musn't be given I.V. or with sulphonamides (they antagonise the action of sulphonamides.)
+
* Care must be taken when giving narrow spectrum penicillins to Guinea Pigs, Rabbits, Gerbils, Hamsters and Chinchillas as they can result in '''fatal ''Clostridium difficile'' colitis'''.