Horse Wormers - Zimecterin, Rotectin 1, Equimectrin
Selamectin Topical - Revolution


Ivermectin is derived from the avermectins, a class of highly active broad-spectrum anti-parasitic agents. It is an anti-parasitic medication used in the treatment of certain worm infections. It works by paralyzing and then killing the offspring of adult worms. It may also slow down the rate at which adult worms reproduce, resulting in fewer worms in the skin, blood, and eyes.


  • Most common intestinal worms (except tapeworms)
  • Most mites
  • Some lice
  • Larval heartworms but not adult heartworms


  • 100 to 200 mcg/lb orally or by injection, once a week for 3 weeks (7)
  • 200 mcg/kg orally or by injection (23)
  • Mites - 0.2 mg/kg orally or by injection, once a week for 3 weeks (14)
  • Pinworms - 25 mg/ml in drinking water 4 days a week for 5 weeks (14)
  • Horse Wormer Paste - roughly 1/2 to 1 grain of rice sized drop per 1lb weight, once a week for three weeks (7)
  • Revolution - 0.10ml once a month (7)

Side Effects

  • Overdose - dilated pupils and a drunken gait that can progress to respiratory paralysis and death if medication is not withdrawn and supportive care is withheld.
  • Anorexia
  • Fatigue
  • Tremors
  • Diarrhoea
  • Constipation


  • It is not effective against fleas, ticks, flies, flukes or tapeworms.
  • Careful dosage is required so as not to overdose, as this can lead to toxicity