Posts Tagged ‘diclazuril’

EPM Drugs Discussed at AAEP

Wednesday, November 23rd, 2011

EPM was certainly discussed at AAEP.  In one class with Dr. Reed and Dr. MacKay, Dr. MacKay said he would wait for FDA approval to use the Oroquin-10.  Dr. MacKay also promotes the use of Marquis at 7X the dose for loading, or at higher doses, longer duration, or mixed with sulpha/pyrimeth.

Marquis is only approved by FDA at 1X for 28 days.  Dr. MacKay is using and publishing protocols that are not FDA approved. Why?  Because Marquis at 1X doesn’t work very well.  The FOI will tell you that 5X doesn’t work any better.  At 10X the FDA approved dose Marquis does have a marginally better success rate.  The  published CNS values of Marquis are not high enough to kill at 1X.

Dr. Andrews is using a protocol with Sulpha/pyrimeth at a 2X dose.  This was shown in the Rebalance trials (FOI) to be toxic.  It is not FDA approved.  Why is he using this?  Because sulpha/pyrimeth at 1X for 270 days doesn’t work very well, and causes anemia.  A 2X dose makes the anemia worse.

Protazil, using the blinded observers, was only 42% effective at 1X dose (it’s on the insert).  MacKay suggests diclazuril be used at 7X the FDA dose, or for longer periods, or mixed with sulpha/pyrimeth.  Only 1X for 28 days is FDA approved.

Dr. Reed suggested to me by consultation, that I use a higher dose of Marquis on Charlie.  This is not an FDA approved protocol.  He certainly did not let me know that.

Dr. Johnson said  on the latest Intervet-sponsored EPM Webinar, they would only talk about FDA-approved drugs.  Less than a minute later, Dr. Andrews is answering web questions about higher, longer drug protocols that are not FDA approved. (Intervet makes Protazil)

None of these used/published protocols are FDA approved.  The veterinarians are not collecting information in a trial.  They do not collect titers after the treatment to see if the horse’s immune system is winding down.  They are simply throwing drugs at the problem, and hoping it will go away.  Does this sound scientific to you?  It shouldn’t.   If your vet has prescribed one of these
protocols to you, they are running a non-FDA-approved mini field trial, with no back-up of proof that it works.  Why?  Because the existing FDA-approved drugs don’t work well.

At least the Oroquin-10 drug trial indicates ‘TRIAL’, is measuring titers before and after the treatment, provides support to vets, and is working its way through the FDA process.  Oroquin-10 is based on a study of decoquinate by Dr. David Lindsay.  This study shows a very high kill rate.   Adding levamisole to the mix seems to help.

If MacKay, Andrews, Johnson and Reed want to use only FDA approved drugs, why are they promoting, using, and publishing non-FDA protocols?  Seems like the pot is calling the kettle black.

Relapse, Relapse, Relapse

Sunday, December 26th, 2010

In this day of immediate media, I should have posted July 20th.  Suffice it to say that one of the relapses was mine, in Lyme Disease.  With the number of changes coming to the EPM world, I’ll try to keep the blog more current.

I sent a Fudge blood sample to Pathogenes to enter him in a study.  This was a study for horses that had previously had EPM, but had been treated and recovered.  I was happy that Fudge had recovered to the point where I took him for his first lesson.  What I got back was that he was in the process of a relapse.  I had both a SAG1 ELISA and a Lymphocyte Proliferation Assay run on his blood.  It showed formation of a very low number of lymphocytes, and a slightly higher SAG1 titer.  Before I could get the diclazuril shipped to me, Fudge had symptoms.

The relapse came about 15 months after his initial diagnosis.  We do not know if this was a replapse or a re-infection.  We started Fudge on a mix of diclazuril, sulphadiazine, and pyrimethamine.  I got a prescription for three months of treatment.  I had previously used just diclazuril, but wanted to see if the S/P would help.  I did not like having to give the medicine on an empty stomach.

Fudge had a Mayhew score of 2.0 during the worst of the infection.  He certainly was unstable when trying to trim his feet.  He dropped much of his food and dragged his rear feet.  As the long summer months wore on, he slowly improved.  After 2.5 months of medicine, Fudge showed some worsening of symptoms.  These were subtle differences in the way he moved, but seen on a daily basis, I could see them.  He was dropping more food, which was measurable.  We sent another sample for tests.  Fudge was having a relapse while still on the medicine.

Anti-protozoal treatments kill or stop reproduction of the pathogens to a degree where the horse’s own immune system can kick in and finish the job.  Reading the drug inserts the drug only kills about 95% of the protozoa.  The horse has to eliminate what is left of the infection.  Fudge was not relapsing due to the drugs.  His relapse was a sign that his immune system was not able to fight even small numbers of the pathogens.