I agree, the Coccidia meds, as well as any and all antibiotics, antifungals, and antiparasitic meds are extremely harsh on their entire gastrointestinal systems, and they upset their stomachs so they lose their appetites. They can also cause diarrhea and even yeast infections because the antibiotics kill off the normal, healthy bacteria that keeps them in stasis and keeps fungi at bay. BeneBac can help restore the healthy bacteria in their intestinal tracts, but the acidophilus already mentioned is much better to settle their stomachs. I'd definitely order some of the specialty reptile acidophilus, and while you're waiting for it to arrive I'd buy a container of Silk brand Soy Yogurt (most common available, Walmart has it) or any other Soy Yogurt that is completely non-dairy and has live and active cultures, and feed him that with an eyedropper instead of the BeneBac, it should settle his stomach much better.
Also, if he's dehydrated, and I'm sure he is, it's because he's not eating. Beardies get most all of their
hydration from their food, both their greens/veggies and their live insects. Most beardies do not drink from a bowl, nor from their
bath. If you see your guy actively
drinking from his
bath then that's one thing, but beardies absolutely do not absorb
hydration through their vents, so
bathing him twice a day is way too much, and could actually be stressing him out more than he already is, which could be also effecting his appetite. The entire "They absorb
hydration through their vents or their scales/skin by soaking in water" is just a myth that got passed around on the internet for some reason, it's absolutely untrue. They absorb absolutely no water at all through their vents, and what little water they may or may not absorb through their scales/skin does not ever make it to their bloodstream to be a form of
hydration, just like humans are not "
hydrated" through their skin by soaking in water. It can actually do the opposite and dehydrate them more, as the osmotic gradient can actually cause fluids to be drawn out of their bodies into the water. This is why our skin tends to become very dry and flakey after a
bath or after swimming unless we use lotion.
The best ways to give your beardie
hydration while he's not eating (or even when he is eating but still seems a bit dehydrated) is to drip either water or better yet use unflavored Pedialyte on his snout with an eyedropper, let him lick a drop off, then drip again, etc. and keep doing it until he stops licking it off. I myself as well as many beardie owners do this to their dragons at least once daily with water, even when they're healthy, just to keep them well
hydrated. I myself believe giving a healthy beardie
hydration this way once a day (same principle as misting them once a day if they lick the water off of their lips and snout) helps to keep their kidneys healthy and may even have a positive effect in reducing the occurances of gout. While your guy is not eating I'd use the unflavored Pedialyte and just drip it on his nose with an eyedropper or an oral syringe for as long as he'll lick it off, and you can also mix some of the unflavored Pedialyte into the Soy Yogurt as well, it will make it easier to drip the Soy Yogurt onto his snout, and he'll get
hydration and electrolytes too. I just buy the generic Walmart brand of unflavored Pedialyte, works great. And he should be less stressed by the multiple
bathing sessions every day, which is also known to unfortunately influence the spread of fungal infections.