Chasteberry is a great alternative for a natural treatment for cushings. Spend alot of time researching cushing for a neighbors senior horse, a mustang. After talking to her owner, I suggested trying the chasteberry which we ordered online. I think we gave her 2 teaspoons a day (I told him he needed to pull/cutback her grain, take her off the sweet version and buy a pellet version), mixed it with the little grain she got. Also advised she really didnt need to graze 24/7, so he started putting her up at night with a couple leaves of hay. Also suggested he start her on a joint supplement, so he went with the MSM (smartpak) that I was giving my mare. She was a different horse within a very short time. SHe was already foundered, but when my neighbor started using my farrier and she was getting trims on a regular basis, that was even improving. She was actually running the fields again, and the heavy signs she had of cushings were actually alot less. And there were no side effects that we noticed.