Zymox is a very common ear med and my holistic vet prescribes it too. Just make sure you follow instructions as to how often and the duration so you'll wipe out the infection well. It may come back and haunt you if not. My two boys both had, and Punkin still has, ear infections, and I don't believe they gave us any antibiotics for it.
What's the shampoo for? We've tried a few shampoos and the only one that worked well is the one we get from the vets, it's an aloe and oatmeal one. Good for itchy and sensitive skin. One bottle lasts at least 6 months so the $20 is very worth it.
Lastly, yes, holistics and homeopaths love the grass and weed supplements. lol. I'm guessing it should boost their immune system.
***Edit: Here's what I found by googling the mix. I'm guessing you spoke about allergies with your vet? It looks like a reputable supplement.
Homeopathic attenuations of antigens; i.e., substances which can produce the production of antibodies. Each PHP allersode combination provides an entire class of common allergic materials along with factors which promote non- specific resistance to allergic stress. Potencies of individual agents are in the 6X- 100X range