Deworming Recommendations 

This topic has recently come into focus as we have learned indiscriminate overuse of deworming products has led to increasing resistance among some parasite populations.

There are three commonly employed methods used for deworming horses. The first method is to follow the a "Targeted Deworming" Protocol.  The second is to administer paste dewormers every 6-8 weeks, on a rotational schedule. The third method is to keep the horse on a daily dewormer and paste deworm twice a year.  We recommend you choose the program that works the best for you, your horse, and horse-keeping situation. 

1. Targeted Deworming Protocol:

This method is based on identifying horses who need treatment and identifying the products that are effective on each particular property.  This method relies on utilizing a McMaster's Fecal Egg Per Gram Test (EPG).  This test quantitatively measures the number of parasite eggs per gram of feces.  Is is commonly performed by a veterinary diagnostic lab or other agricultural or extension office.

The idea is to time deworming treatments for optimal impact and use a dewormer proven effective against the target parasite.  This method will vary due to geographical differences in climates that affect parasite transmission.  Working with your veterinarian, you can develop an individualized approach that is specific for each property and horse.

For more information, please read Equus (Feb. 2011) Special Deworming Report here:                        Equus Special Deworming Report.pdf   

2. Paste Deworming (Rotational) Protocol:

This method employs the rotational use of dewormers administered on a specific schedule. 

This schedule is recommended for the Southeastern United States for horses not on a continuous deworming program. ( i.e. daily Strongid C 2X or Continuex):

January - Oxibendazole (Anthelcide) or Fenbendazole (Panacur or Safeguard)

March - Ivermectin/praziquantel combination (Equimax or Zimectrin Gold) **

May - Oxibendazole (Anthelcide) or Fenbendazole (Panacur or Safeguard)

July - Ivermectin (Zimectrin or Equell)

September - Oxibendazole (Anthelcide) or Fenbendazole (Panacur or Safeguard) 

   Some horse owners choose this time of year to use a double dose of Fenbendazole (Panacur) to kill any encysted small strongyles.  This can be repeated for 4 more days if horse is showing signs of suspected small strongyle infestation (poor coat, diarrhea, unthrifty).   This product is conveniently packaged and sold as a Panacur Power Pac.

November - Ivermectin/Praziquantel combination (Equimax or Zimectrin Gold) **

++ Remember to read the active ingredient. Many times horse owners are rotating among various generics of the same drug.  The active ingredient will be written on the label in the parenthesis following the trade name.  Example: Strongid (pyrantel pamoate)   Exodus (pyrantel pamoate)


**To be most effective, timing of Ivermectin needs to coincide with the frost cycle.  (i.e. administered after the first frost of the year - usually November - and after the last frost of the year - usually March).      It can be administered at other times of the year, as well, but in order to effectively manage the bot cycle, it needs to coincide with the frost cycle.
Also, the drug praziquantel is used to manage Tapeworms, which none of the other dewormers manage.  You can choose to do it once or twice a year, depending on your particular stocking density.  If you choose to do it only once a year, then use plain Zimectrin or Ivermectin for one of your "frost cycle" dewormings and use Equimax or Zimectrin Gold for the other.


The above example shows a two way rotation, primarily.  You can add in Strongid (Pyrantel Pamoate) and make it a three way rotation, if you prefer.  Discuss with your veterinarian the best method for your particular horse.

3. Daily Deworming Protocol:

Deworm December and June with Ivermectin/praziquantel combination(Equimax or Zimectrin Gold) and keep horse on a daily dewormer, pyrantel pamoate (Strongid C 2X or Equi Aid CW).

** Before starting the continuous deworming program, deworm with Equimax or Zimectrin Gold.

4. Foal Deworming Protocol:

Beginning at two months of age, begin deworming with Pyrantel Pamoate (Strongid).  Then deworm again at three months of age with Ivermectin (Equell or Zimectrin).  From that point onward, choose which rotate the foal into one of the above regular deworming protocols - targeted, daily, or bi-monthly (paste).