albendazole toxic?

Question
Can you suggest to me a body of data including necropsy reports with toxicology results, literature or case reports that prove albendazole is toxic to rabbits?  If you have this evidence, please make it available to veterinarians or publish it in a peer-reviewed journal. It is a little frustrating when you try to help rabbits and get blind sided by non published information from clients that you are educating.  Exotic DVM is does not meet the standards of a scientific journal. Its articles are informative but are base on upon scientific method.  These are "In My Experience" type journals. If you are interested, I will co write an article for JAVMA if the data you have suggest a true toxicity. Veterinarians get penalized by state veterinary boards when they malpractice as you are suggesting by this medications use.  Thanks

Answer
Dear Todd,

The data indicating that albendazole is potentially toxic to rabbits (and possibly other mammals) are, at this point, somewhat anecdotal.  Sadly, problems like this often come to light only after individual case studies are made public, and a pattern is noticed.  At this time, I do not believe there have been any controlled studies done on the toxicity of albendazole specifically in rabbits.

I did find this one study:

http://www.inchem.org/documents/jecfa/jecmono/v25je02.htm

suggesting toxicity of albendazole in rabbits, but not other species.

I also quote another rabbit rescuer (name withheld), who published this on one of the many rabbit health lists:

"What ever you use, please don't use Albendazole.  We have documented
proof from pathology that it killed a young, healthy bunny who had only
a very low positive titer and no symptoms at all and no internal damage
from E-C that pathology found.  The lab conclusively determined that
Albendazole was the fatal aspect.   At the same time there were 5 other
rabbits on Albendazole that died within a two week period.  Even
though we couldn't prove conclusively that Albendazole was the killer on
all of them, the circumstantial evidence that all were put on Albendazole
within a couple of weeks of each other and all died within a couple of
weeks of each other speaks for itself."

And this from a veterinarian in Switzerland:

"Here in Switzerland, Prof Desplazes (VetSuisse Fac, University of Zurich,
from the Suter et al. paper, about fenbendazole use) specifically warned me
and others ***never*** to use albendazole in rabbits. During this study,
they experience acute death minutes after administrating normal dosis of
albendazole to healthy rabbits.

Unfortunately, this is from oral communication, and has never been
published. I am sure though that he will give you more info, if you contact
him directly. This had led some US vet to discard the warning, as:
- never had any problems,
- this warning is not published,
- is coming from Europe,
- the results obtained by Suter et al. research may not be as not reliable
as coming from Europe where research standards may not be the same as high
as in the USA.

(Yes, I have heard this all, and very sad knowing that much of the rabbit
vet books are written by European rabbit savvy vets !!!)

and continue to treat E. cuniculi with albendazole only, not even
considering the use of fenbendazole, or oxibendazole.

Attempts using pyrimethamine or Marquis have been attempted, in cases where
the benzimidazole have failed to work, with some success."

Given these reports, I would be very leery about giving any rabbit albendazole when there are much safer alternatives.

I do agree that a controlled study would be better.  But no one who loves and cares for rabbits wants to sacrifice rabbits for this.  Better to be safe than sorry.

I hope this helps.

Dana