Metronidazole (Flagyl)

Metronidazole
Antibiotic, Antiparasitic, Anti-inflammatory
(Flagyl)
By Dr. Karen Burgess

 

Brand name and formulations

  • Metronidazole (generic)
  • Flagyl (brand name)
  • Tablets, Capsules, and Injectable

What is Metronidazole?
Metronidazole’s mechanism of action is not fully understood.  Common uses include the treatment of Giardia, a variety of anaerobic bacteria including Clostridia, and in the treatment of intestinal inflammation/diarrhea.  Metronidazole is also effective in the treatment of nervous system disease unlike many other antibiotics.

How is Metronidazole given and what if a dose is missed?
Metronidazole is typically prescribed for twice daily dosing.  If a dose is missed and it is less than 12 hours late, go ahead and give missed dose.  If it is within 12 hours of the next dose, skip a dose and resume regular schedule with next dose.  Metronidazole have a bitter somewhat unpleasant taste and may be easier to administer in capsule form.

How should Metronidazole be stored?
Store at room temperature and protected from light.

What side effects are associated with Metronidazole?
Metronidazole may cause nausea and vomiting in some dogs.  Giving on a full stomach may help with these signs.  Neurologic side effects (walking as if drunk, rapid eye movements, depression, seizures) can occur in particular with higher doses or longer duration therapy.  Some cats will develop a fever in response to metronidazole therapy.  Animals with liver disease may require dose reduction when being given metronidazole.

What drugs should not be given with Metronidazole?
Efficacy of metronidazole may be effected by concurrent use of phenobarbital.

What follow up is necessary with Metronidazole use?
Medication should be used for some time after signs of illness or disease are gone.  Notify us if a refill is necessary.