calmers and magnessium

[Fii]

sorry if this has been done before, iv'e onley used one type of calmer which was Magnitude frome Equine America which i think was nearly 100% magnesium oxide,the other day i was reading the back of a tub of epsom salts and it said prolonged use may cause an excess of magnessium in the blood which may cause tiredness and weakness.Epsome salts has 100% magnesium sulphate.now i dont know what other calmers have in them but is this a worry? are we calming our horses by making them sleepy and weak? how much do we know about the stuff we are buying and feeding to our animals? also whats the differance between magnessium oxide and magnessium sulphate? maybe im just being silly, feel free to tell me if iam

 

[MegaBeast]

Basically Magnesium only works as a calmer if the horse is deficient. There is sound science behind, a lack of magnesium causes a rise in intracellular calcium which mimics the action of adrenaline however this only works when magnesium is not sufficient in the diet. It is a common problem as a lot of "improved" grass is magnesium deficient.

Very little difference indeed between oxide/sulphate, basically different salts of magnesium with slightly differing bioavailabilities and solubilities but both do the same job so far as I can make out.

I believe that an excess of magnesium doesn't do any harm, but can make stools runny, any excess isn't absorbed but is passed through the body.