Solitude IGR Feed Through Fly Preventive

Regularly: $114.99

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6 lb
Less than $0.45/DAY
(192 day supply)


In Stock. Usually Ships within 24 hours.

20 lb
Less than $0.37/DAY
(640 day supply)


In Stock. Usually Ships within 24 hours.

Shipping weight = 7.00 lbs.



Product Summary:

SOLITUDE® IGR Insect Growth Regulator Feed-Through Fly Preventive
by Zoetis, formerly Pfizer

You can substantially reduce your fly population simply by adding a scoop of SOLITUDE® IGR daily to your horse's feed. Regardless of the farms around you, it will reduce flies at your barn. Use it during fly season to eliminate larvae development. It's economical to use, and safe for other pets that might also be eating your horse's manure.

SOLITUDE® IGR (cyromazine) is a non-organophosphate that has been safely used in horses since 2001 and undergone extensive research to prove its effectiveness and safety. It provides feed-through fly prevention and control of house and stable flies in and around horses, horse barns, stables, paddocks, and race tracks. When mixed into a horse's ration daily according to the directions, it works to prevent house and stable fly development. Significant results may be observed within two weeks, but the full benefit should be realized within four to six weeks of administration as the adult populations die off.

Cyromazine, the active ingredient in SOLITUDE® IGR, has a well-documented safety and efficacy profile, It is an insect growth regulator that works on the fly's chitin exoskeleton and is very species-specific to house and stable flies. As the horse is fed cyromazine, it passes through the horse and is excreted in the manure. House flies and stable flies lay their eggs in the manure and the eggs subsequently hatch into the larval or maggot stage. As the maturing maggots feed on the treated manure, they become unable to successfully develop into adult flies because cyromazine inhibits the proper formation of chitin. The immature stage of the fly dies. Cyromazine has no effect on the chitin of the adult fly.


  • Greatly reduces the need for neurotoxic pesticide sprays and overhead fly systems, creating a healthier environment for horses, staff, and riders
  • Intended for use only in equidae including horses, mules, and donkeys
  • Just one scoop per day per horse, no matter the weight or size of horse
  • Once excreted, breaks down to a melamine monomer, a slow release nitrogen fertilizer
  • Repeated studies show up to 100% efficacy in inhibiting larvae development
  • Studies have proven 99.5% effectiveness against stable flies and 100% effectiveness against house flies, with no effect on horses, other mammals or beneficial insects
Item Specifications:

6 lb. pail (192 doses)
20 lb. pail (640 doses)

Start feeding SOLITUDE® IGR early in the spring before flies begin to appear, and continue feeding throughout the summer and into the fall until cold weather inhibits fly development. In some cases, supplemental fly control measures may be needed in and around paddocks and stables to control adult house flies and stable flies, which can breed not only in manure, but in other decaying vegetable matter or silage on premises. SOLITUDE® IGR will provide a high degree of fly control and will give the best results when integrated with a well-managed fly control program that includes appropriate sanitary and management practices to reduce the number and size of fly breeding sites.

To maximize the effectiveness, horses must be fed individually. Made from alfalfa, these pellets are to be fed top-dressed on grain or mixed with the horse's total ration to provide 300mg of cyromazine per horse per day.
Using 1/2 oz. scoop supplied with the product, mix one scoop of SOLITUDE® IGR in the horse's ration every day.

Do not contaminate water, food or feed by storage and disposal. Wastes resulting from the use of this product may be disposed of on site or at an approved waste disposal facility. Harmful if inhaled or absorbed through the skin. Avoid breathing dust and contact with skin or clothing. May cause skin sensitization reactions in certain individuals. Wash thoroughly with soap and water after handling. Do not apply directly to water.

Downloadable Resources
Product LabelManufacturer Information
MSDS SheetManufacturer Information
Key Benefits & DosageManufacturer Information
Style Item Number Model Number UPC
2 lb SLT101692 002 PFJ 115
6 lb SLT101692 006 026619 1008721908598
20 lb SLT101692 020 026620 087219086001

Product Reviews by Customers

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Browse 17 questions Browse 17 questions and 120 answers
Why did you choose this? Store
This product was vet recommended for safe and effective fly control. I have been using it for many years. I use very little fly spray which ends up saving time and money.
nancy L on Sep 4, 2019
Janine C on Jun 28, 2019
This product was vet recommended for safe and effective fly control. I have been using it for many years. I use very little fly spray which ends up saving time and money.
nancy L on Sep 4, 2019
Works like a charm for our 9 horses in the barn!
Connie C on Aug 1, 2019
Janine C on Jun 28, 2019
This is the only product that actually works on keeping down the flies at my 32-horse facility. Good price too.
Dawn A on Apr 18, 2019
Another regimen in fly control..especially since I compost
Adrieanne M on Mar 28, 2019
I've been using Solitude for many years. The amount of the fly population that is reduced is quite significant. I use very little fly spray.
nancy L on Mar 25, 2019
I use Solitude because it works. I combine it with fly predators and almost eliminate my fly burden each year.
Cheryl R on Mar 25, 2019
First time using....recommended by my vet.
Debbie C on Mar 15, 2019
Recommended by our vet.
Lori C on Mar 1, 2019
Seems to work - fewer flies than other farms.
Susan V on Feb 28, 2019
Works great!
Anita C on Feb 18, 2019
It works
Keith L on Feb 10, 2019
sounds safe for controlling flies
niels l on Dec 19, 2018
We use this in S. Fla, makes a HUGE difference in fly control. A nearby neighbor, that we can see through an adjoining 5 acre property, clearly does not do much in fly control...all tails swish constantly. With this and some other measures, the flies don't invade our 15 acres, as it did prior to using. Was worried it may cause issues in bellies, etc, but not at all. Flies cause more problems than anything, especially here.
Gena B on Dec 14, 2018
It works. Together with Fly Predators, our barn and horses are nearly fly free.
Sheila O on Nov 18, 2018
Good stuff. Highly recommend. Have used for years.
Elsie W on Aug 31, 2018
Its the only product that truly works. It is also safe for mares and foals
Allison K on Aug 31, 2018
Great customer reviews...... never used this before either
Carol D on Aug 25, 2018
I have been using Solitude for years. I have a very significant reduction of flies. This product is also the safest for all equine compared to other products that kill fly larvae in the manure (IGR).
nancy L on Aug 15, 2018
This product really helps with fly reduction. I recommend it.
Heather L on Aug 14, 2018
It takes about two weeks to see results, but it virtually eliminates all kinds of flies from my property. It works very well and none of my horses had ever had a side effect. All my horses are together in pasture so I just walk around once daily and feed them a half-ounce which they eat out of my hand.
Sandra W on Aug 10, 2018
The war against flies continues. So far, in 2018, (thanks to this product), I'm winning.
Tracy B on Aug 3, 2018
Product was offered at the lowest price
P E on Aug 3, 2018
It works!
Jane O on Aug 1, 2018
Recommended by a friend
Meredith H on Jul 29, 2018
Solitude IGR really works. I have 4 horses and barely any flies using Solitude IGR. I have used other feed through products that do not work at all.
Margaret Y on Jul 23, 2018
This stuff really works. After using it for a year, it has drastically reduced the fly population that just one horse can produce.
Nancy H on Jul 14, 2018
Meredith H on Jul 8, 2018
Its the only product that really works and is safe for pregnant mares and foals
Allison K on Jul 6, 2018
fly control
George V on Jun 22, 2018
It truly works.
Cindy D on Jun 19, 2018
Reviews say it works, so I will give it a try
Kim K on Jun 11, 2018
After breaking the cycle I hardly see any flies even outside my barn during the summer. Even on the manure pile there's not many. Normally there's thousands!
Teresa R on Jun 8, 2018
It works the best of anything I have tried. Definitely reduced the fly population more than the predators ever did and am having to use less fly spray. The thoroughbreds aren't so bothered by flies that they drop weight.
MARYANNE G on Jun 7, 2018
fly problem 80% better afer feeding solitude
elizabeth c on Jun 1, 2018
Works very well, easy dosing too!
Robin G on May 30, 2018
Solitude IGR and fly predators have almost completely eliminated my fly problems and I havea 400 cow/calf units grazing on 4,000 acres less than a half mile away !
SUSAN W on May 25, 2018
We used this product last spring and summer and it really works.There were a few flys around our horses, but none eating them or around their eyes. Works way better than any fly spray we have used in the past, It even cut down on the flys around our house
Gwen W on May 25, 2018
i love the way this product helps to reduce the fly population.
Michelle V on May 17, 2018
Recommended by a friend. I didn't see any flies on her horses!
Katherine E on May 15, 2018
I feel it helps with fly control along with the use of Fly Predators. I've been using this product for at least 10 years. People frequently remark about the fact that I seem to have less flys than most barn. In fact, I've noticed that myself.
Kathleen R on May 11, 2018
We tried it on our farm last year and were thrilled with the results! Looking forward to another fly free summer.
Katharine J on May 10, 2018
Have always used Solitude IGR because it works. I have two veterinarians as one is my Equine specialist and one (my husband) is my small animal specialist and both recommend Solitude. I use it along with good husbandry around the barn.
TANYA R on May 4, 2018
it works!
jill g on May 1, 2018
I like that is it one scoop per horse no matter weight, the pellets are palatable and the cost per dose is good. It worked so well last year we had a noticeable improvement in the amount of flies around the barn including the big biting horse flies. Will use every year.
DEBORAH M on Mar 29, 2018
I have used this in my stable for the last three years. I have seen a significant reduction in flies. Great product!
Cheri B on Mar 19, 2018
Have been told that it is quite effective. WIll be my first time trying it.
Monik J on Mar 9, 2018
I find the feed through fly control which keeps fly larva from maturing is the most effective in keeping down the fly population. It works great at my farm which is isolated from other livestock farms.
c P on Mar 7, 2018
safe and effective
KelleyJo on Mar 5, 2018
best product I've found for eliminating flies, have tried everything. Start before the flies become established, end of winter, very early spring.
Terri M on Mar 2, 2018
Works like a charm for our 9 horses in the barn!
Connie C on Aug 1, 2019
This is the only product that actually works on keeping down the flies at my 32-horse facility. Good price too.
Dawn A on Apr 18, 2019
Is this safe for mini horse and mini donkeys?
A shopper on Jun 21, 2019
BEST ANSWER: This is a question you might want to ask your vet, just to make sure your little ones are good candidates for this product. I have no experience with donkeys, but I fed this product to every member of my herd, which included a Shetland pony and two miniature horses as well as several full-sized horses. The little ones and the big horses found the pellets palatable and seemed to do well on them. The dosage recommended by the manufacturer is the same, regardless of the equine's weight, so your little ones would be getting the same amount as a big horse.
Does this product work to repel or diminish the population of Ceratopogonidae ? AKA no see-ums, biting midges, etc. My horse has severe allergies.
L.K. M on Jan 11, 2019
BEST ANSWER: It does not repel flies. It passes through the horses gut and acts by preventing fly larvae from developing once eggs are laid in their poo. So overall fly population drops. I don’t know how well it works on midges specifically. I suspect not as well as other biiing flies. One of my horses also has severe allergies, and he still suffers in the summer. But he does better and I do have less flies overall when my horses are on this product. I recommend it to all my horse friends!!
Does Solitude work well when I pick up the manure every day ?
A shopper on Aug 22, 2018
BEST ANSWER: Yrs it works provided all horses in the area are on it and provided you not only pick up the manure daily (preferably 2x) but have it hauled away. Our barn made the mistake of spreading the waste on a hillside above our barn. This attracts flies from miles around so the progress you make w/Solitude is lost!
Can I feed garlic with the Solitude?
A shopper on Jun 10, 2018
BEST ANSWER: Yes, I give my horse Garlic Powder. You will have to gradually build up, unless your horse just like the taste. Per my vet I was not to give more than a tsp. So I stated at 1/8 tsp for a few days, then added gradually up to full amount. Check with your vet first before given, just incase your guys have some medical issues. Like one of mine had RDC last yr and had to be taken off.
Can solitude be used on longhorn cattle?
Jon P on May 25, 2018
BEST ANSWER: Not sure but I can say that it’s safe to feed to pregnant mares and foals. When I had questions about the safety I called Pfizer directly and they answered my questions in regards to safety for broodmares. They are the only
Brand that has done the research and actually works
one scoop per day for 1 horse, how long does this last?
A shopper on May 1, 2018
BEST ANSWER: The daily dose is one-half ounce (scoop is included), so the 6lb bucket contains 192 doses, and the 20lb contains 640 doses.
Does it work with mosquitoes?
Rebecca T on Sep 25, 2017
BEST ANSWER: I can't really answer this. I don't live in an area that has a lot of mosquitoes, but when I have gone into those areas, my horse doesn't get bitten like my friends horse. I also use Pyranha fly spray and she uses something she makes that is more natural, so that could also be the difference. I can tell you that it is the best stuff I've ever used for flies and my horses don't get the normal bites and egg laying that other horses do in my area.
Will left over Solitude stay good without mold until next season?
Lori W on Jul 29, 2017
BEST ANSWER: It likely depends on where you store it. I live in AZ so there isn't any "next season". I use it year round. We don't have a lot of humidity but when we do have some (like this month and the next two), this product is fine in my tack room that isn't particularly well sealed. I've never had rancidity, mold or anything "off" and I buy huge containers of it at a time. I would think, if you store it for a season, you should do so in a clean, dry place.
I board 24 horses and will be putting them on Solitude beginning 5/1/2017; It figures out to 720 doses per month; which is the most economical way to buy this? (4) of the 6 pound containers per month or one 6 pound and one 20 pound per month?
A shopper on Mar 21, 2017
BEST ANSWER: I just bought a 20 pound. It says 640 doses on the container. I buy everything in bulk because it IS cheaper to do so. So I guess the real question would be why buy any in the smaller size? If you start off with 2 20 pound containers, whatever you havent used at the end of the first month will still be good the next month. Or put it on auto order, save an additional 10% because you did, and have it delivered every 3 weeks.
Hi I am pregnant and just found out my employer uses this and I mix grain and supplements with my hands. Are there any concerns I should be telling my dr about?
Barbara H on Sep 16, 2016
BEST ANSWER: We would suggest consulting your doctor. Below is the link for the MSDS sheet.
Can this product be used with Cows? I have a cow living with my horses and want to know if he can also be given it...
Janet H on Sep 2, 2016
BEST ANSWER: I'm not a vet and if I were you I would check with yours. As a "layman", I would think it would not hurt (if you're not using the cow for milk or food). I would also think that there are less expensive means for a cow. I have seen bags hanging in their pastures at a nearby cattle ranch. Check out the Python Dust Bag for a start.
Is this harmful if dogs eat the manure?
Debbie L on May 23, 2016
BEST ANSWER: Debbie I have a 8yr. old corgi mix and he is not a fan of eating manure BUT will help the donkey eat his supper every night if I let him which contains Solitude., this practice has not seemed to have affected his well-being in 6 yrs. HOWEVER my dog doesn't seem to be affected by anything he gets into. You always must take into consideration your dogs breed and tolerance level to foreign intake.. (ie when I had Boxers they were not allowed anywhere near the barn area ) and as always when in doubt ... ask your vet .
Is this product safe for in-foal mares/foals?
K S on Feb 16, 2016
BEST ANSWER: No. My equine repro vet advised against it. I used an organic fly spray while she was in foal. The foal is healthy.
how long will the 6lbs last 5 horses?
Vicki H on May 4, 2015
BEST ANSWER: It's one ounce per day per animal no matter what weight the animal, I believe, so you can figure from that. Also, you can call the customer service for Pfizer and they would let you know exactly. The state line tack description also says a day supply on the description page, so that would also be a way to figure. We have four animals and I order 2/year and use about 9 pounds of it and have "left overs" for the next year. Actually I'm glad you asked because I need to order another six pounds. It's very to feed, sprinkle it in the feed you use, and it works very well. Better, I think, than the insects. We have our manure pile about 100 feet from the house and have never had a fly problem by the house, except in very late summer and those flies are hard to get away from whatever we've used.
We also have two mini donkeys besides three horses my question is do we give the donkeys the same amount of solitude as the horses in their supplement dish? thank you dblm ranch
Margaret N on Jan 13, 2015
BEST ANSWER: We have welsh ponies, weight around 500# ea and we give them a scoop. One of our mares had kidney disease and we especially asked our vet about that issue. She phoned the Pfizer co and they said it was ok, we never had a problem. If you want to know for sure, you could probably call Pfizer, they must have a customer service dept. We've used it for five years and are very happy with it. Our manure pile is close and we have had minimal problems, even in August/Sept which are our worst months. We tried the bugs, but this is great.
How long can this product be stored indoors before it is no longer effective? Does the 10% auto ship apply to the discounted price today?
A shopper on Jan 7, 2015