"..What substance in
it would make it illegal?...."
Milk of Magnesia is hydrated magnesium oxide.
As such it falls under the category of normally occurring substance.
Magnesium is absolutely required for life. The wrong level in the diet
will lead to electrolyte problems. If enough were to be administered, it
would be found in "abnormal amounts" and thus forbidden.
Like the rest of the inorganic, ionic family of
chemical compounds (electrolytes) that are required for life, it is presumably
legal if not administered so that there is an "abnormal" amount in the
horse. Since excess of electrolytes makes horses sick, just like a lack of
same, I doubt that anyone in authority is particularly worried about the
administration of MOM to horses during rides.
Ed.
Ed & Wendy Hauser 2994 Mittower
Road Victor, MT 59875
