This doesn't sound like Fenbendazole (Panacur). It is probably the safest dewormer we could use, of course depending on what type of parasite you're dealing with. That's not to say it's impossible to overdose a leo with Panacur, it's just unlikely unless someone really didn't know what they were doing and really messed up somehow.
Metronidazole (flagyl)or Ivomec, on the other hand, would probably be really easy to overdose. I believe giving an incorrect dosage of flagyl could cause brain or nervous system problems.
As for gut flora, that's a pretty interesting statement. I'd like to see some sort of clinical information on the common stuff found in leopard gecko stomachs. I've read that some vets won't even treat mild parasite (oxyurid) infections and others try to get rid of them completely.
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Rob Jenkins
Have you seen the GeckoCam?
Herptopia Reptiles
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