Executive Summary

  • This article describes our testing of Fenbendazole bioequivalence.


A significant issue with the FDA is that they do not appropriately test manufacturing facilities; in particular, their testing is far worse in foreign manufacturing facilities. This has created a dual pricing market, where the FBZ from the higher quality countries is very expensive — even though the item is generic. Then inexpensive sources are of dubious bioequivalence. The case of FBZ is why it is not as simple as a drug simply becoming a generic, and then the price becomes reasonable for a high-quality source.

The Problem With the FDA’s Lack of Testing and Bioequivalence Curves

The FDA does not test the outcomes of drugs in people but instead allows manufacturers to submit bioequivalence tests performed in labs. However, the standards for measuring bioequivalence are very low. The following quote is from the book Bottle of Lies.

Patients getting switched from one generic to another might be on the low end one day; the high end the next. The FDA allowed drug companies to use different additional ingredients, known as excipients, that could be of lower quality. Those differences could affect a drug’s bioavailability, the amount of drug potentially absorbed into the bloodstream. But there was another problem that really drew Graedon’s attention. Generic drug companies submitted the results of patients’ blood tests in the form of bioequivalence curves. The graphs consisted o a vertical axis called Cmax, which mapped the maximum concentration of drugs in the blood, and a horizontal axis called Tmax, the time-to maximum concentration. The resulting curve looked like an upside-down U. The FDA was using the highest point on that curve, peak drug concentration, to assess the rate of absorption into the blood. But peak drug concentration, the point at which the blood had absorbed the largest amount of drug, was a single number at one point in time. The FDA was using that point as a stand-in or “rate of absorption.” So long as the generic hit a similar peak o drug concentration in the blood as the brand name, it could be deemed bioequivalent, even the two curves reflecting the time to that peak looked totally different. Two different curves indicated two entirely different experiences in the body, Graedon realized. The measurement of time to maximum concentration, the horizontal axis, was crucial or time-release drugs, which had not been widely available when the DA first cre-ated its bioequivalence standard in 1992. That standard had not been significantly updated since then. “The time to Tmax can vary all over the place and they don’t give a damn.”

Our Approach to Testing

We have stepped in to address this issue by performing our independent testing but by doing actual animal testing. Technical lab tests are far less accurate than tests with real subjects. However, the problem is that many things that Fenbendazole is helpful for are difficult and expensive to test. So we needed to find an outcome that was easy to observe and test. Luckily, this outcome is known and goes back to the origin of the drug.

Description of The Test

Over two months, we purchased and tested several products for their most easily observable and measurable item: effectiveness against parasites. As we cover in detail in articles for subscribers at this site, Fenbendazole is effective against many things; however, parasites are the most measurable thing to test. As soon as the item is effective against parasites, its other benefits can be realized. We used the whipworm (infecting the rabbits with whipworm, and then applying Fenbendazole to them) to test the effectiveness of the six different well-priced Fenbendazole brands thus far on rabbits and have selected our favorite manufactured brand.

Why We Were Able to Test in a Reliable Fashion

The initial tests of Fenbendazole were published, and we copied those tests. However, all of our tests were with well-priced generics.

Where We Got the Testing Protocol

We followed this well-established protocol that we found reading the research into animal testing. FBZ works the same way in humans as it does in animals. However, we tested human FBZ on rabbits. Finally, if a less effective brand is not giving the desired outcome, all rabbits are given the most effective brand at the end of the test. We currently have 6 of these testing rabbits, and they are great pets and test subjects, are well cared for, and have an open area where they forage in a controlled setting.

Performing Effective Comparison Testing

And because of the measurability of mite infection, mite growth, and mite elimination in rabbits, we can test the effectiveness of FBZ between different manufactured items. This test is also “real world” as it is tested in animals with measurable outcomes.

Covering Testing Costs

Subscribers receive our most up-to-date testing. After weeks of discussions with a supplier to carry the FBZ that passed our tests, they have just brought their website for those we recommend to them online. Subscribe to the site, and you will have access to this source information.

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