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Not All Omeprazoles
Are Created Equal

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Studies shows some products have inconsistent amounts of the active ingredient used to prevent or treat equine stomach ulcers1

Veterinarians give 100 percent to their clients and patients. They'll do whatever it takes. But what if the equine health care product chosen is only giving 36.3 percent?1

Unfortunately, studies show that might be the case. Especially when it comes to products claiming to treat and/or prevent equine stomach ulcers, a condition affecting two out of three nonracing competitive horses.2

Veterinarians and horse owners need to be wary when& Drug Administration (FDA) have confirmed that not all products are created equal—or well.1,3 And just because the product's label contains a statement doesn't necessarily make it true.

“Veterinarians and horse owners should be concerned that they aren't always getting what they are paying for,” says Megan Green, DVM, manager, large animal veterinary services, Merial. “But this has been an ongoing problem. Some manufacturers have been making claims that simply aren't true.”

The Studies

In studies of products claiming to treat or prevent equine stomach ulcers, some products were found to have inconsistent and varying amounts of the active ingredient used to treat or prevent ulcers – omeprazole. The charts show the wide range of omeprazole found in four different”equine ulcer“ products, from as little as 27 percent to as much as 126 percent.

Ultimately, the FDA issued warning letters to the manufacturers of GastroMax 3 and Gastrotec, along with multiple other manufacturers (see complete list in the news release "FDA Issues Warning Letters for Unapproved Omeprazole Drugs Marketed for Use in Horses," found here: http://www.fda.gov/animalveterinary/newsevents/cvmupdates/ucm422694.htm.)

The FDA issued these warnings because the manufacturers were marketing their unapproved animal drugs “for use in the mitigation, treatment, or prevention of disease in animals.” Unapproved drugs have not been tested by the agency for safety or effectiveness, which makes them not only unapproved, but illegal.

“Studies and tests conducted have confirmed that not all products are created equal or well.”

“The wide variation of active ingredient found in these products by Dr. Stanley and the FDA really isn't a surprise,” says Green. “Omeprazole is highly unstable, which is why it's so important that it is manufactured under the good manufacturing practices established by the FDA.”

Besides the stability challenge inherent with omeprazole, its ability to travel through a horse's highly acidic stomach is also a concern with unproven and unapproved drugs. “For omeprazole to work, it has to travel through the horse's stomach, which requires a special formulation,” Green adds.

That special formulation is found in the only proven and FDA-approved products for equine stomach ulcers, which are ULCERGARD® (omeprazole) for prevention and GASTROGARD® ((omeprazole) for treatment.9,10 These products are manufactured following stringent FDA guidelines, ensuring quality and efficacy.

The FDA approval process ensures a drug is safe, effective and has accurate, comprehensive labeling. In addition, following initial FDA approval, the FDA continually monitors the drug. All FDA-approved drugs for use in animals have either a New Animal Drug Application (NADA) or an Abbreviated New Animal Drug Application (ANADA) number. These numbers and the statement ”Approved by the FDA“ are usually found on the drug's label.

Unfortunately, in spite of the warning letters issued by the FDA, some illegally marketed products remain available, so veterinarians and horse owners should be vigilant about checking the labels to ensure they are getting products that have been proven to contain the appropriate amount of omeprazole and proven to work. Otherwise, money will be wasted and the horse's health will be in question.

Knowing which horse products are safe and effective is critical. Visit www.equinedrugfacts.com, a site that helps explain the different types of products on the market and the FDA approval process.

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1FDA Issues Warning Letters for Unapproved Omeprazole Drugs Marketed for Use in Horses. Available at: http://www.fda.gov/AnimalVeterinary/NewsEvents/CVMUpdates/ucm422694.htm. Accessed January 29, 2015.
2Mitchell RD. Prevalence of gastric ulcers in hunter/jumper and dressage horses evaluated for poor performance. Association for Equine Sports Medicine. September 2001.
3Stanley SD, Knych HK. Comparison of Pharmaceutical Equivalence for Commercially Available Preparations of Omeprazole. AAEP Proceedings. 2011;57:63.
4Data on file at Merial.
5Data on file at Merial.
6Data on file at Merial.
7FDA correspondence to Cox Veterinary Laboratory, Inc. Available at: http://www.fda.gov/ICECI/EnforcementActions/WarningLetters/2014/ucm422544.htm. Accessed November 14, 2014.
8FDA correspondence to Horse PreRace. Available at: http://www.fda.gov/ICECI/EnforcementActions/WarningLetters/2014/ucm421133.htm. Accessed November 14, 2014.
9ULCERGARD product label.
10GASTROGARD product label.