Salt
Salt is involved in all transactions involving fluid in the body. 
Sodium acts with potassium to pump fluid in and out of the cell. Salt (sodium chloride) has two actions. In the mouth, salt first releases a flood of saliva, then dries the mouth and dries the body. 
Salt is hydrophilic, it takes up water. Where there are problems with fluid balance in the body salt "natrum muriaticum" can be a very useful homeopathic remedy for people that it suits, and can work very deeply. In first aid treatment of colds, it suits colds where the nose first floods, then dries, or where one side of the nose is dry and obstructed and the other is dripping and we see an alternation of fluid and dryness. It is also a remedy that can, when it suits the nature of a person help release deep grief that has been held inside for years.

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