De-worming, is there a better way?

Our horse has had diarrhea for at least two months as well as when he passes gas it will include liquid. He has been on psyllium but there has been no real improvement (he did have some sand but that has improved). His appetite is fine. Our vet did a fecal sample and found three different parasites. The vet prescribed Ivermectin, but there been no improvement. The vet came out again and tested the fecal sample and put him on a power pack for seven days.   In this case, is there a more mild approach to de-worming then these chemicals? 

 thanks  John

Always a better way! See magazine for article on deworming and check out our product called Worm Check . It does not kill anything but boosts the immune system to help the body rid itself.
I would highly suggest our Gut Check to help with the diarrhea. It is full of pre and pro biotics PLUS enzymes t help the gut in general. Also suggested is our Aller Check to Boost the immune system on a daily basis especially considering the apparent severity of  this situation.
Please too see the info/audio on What To Feed Your Horse. Sounds like a change in diet will help overall.
Generally such situations do well. some take some time however but do expect results.
Thanks for asking!