Not the most nectar subject, but useful information nevertheless.

This in taken from Dr.Christopher's book, "The School of Natural Healing."

"Excess mucus in the body often results from partial decomposition of blood plasma, due to a nutritional shortage of potassium chloride, the element that enables fibrin to remain in solution in the blood.
In all inflammatory processes, there is an exudation or sweating out of fibrin from the blood into the surrounding tissue. This exuded fibrin becomes non-functional and insoluble. No new fibrin can be formed without the aid of potassium chloride. This exuded fibrin is called catarrh. Advanced stages of fibrinous exudation in different organs is variously named cystitis, cysts, adhesions etc. When the chemical balance of the blood is upset nature calls for potassium chloride. If this element is not available the body will take these two elements from any other compound containing them, such as potassium phosphate( robbing the nerves) or calcium chloride( robbing the heart muscle)."
This can compound into so many imbalances.
The following herbs are good sources of potassium chloride.
Bladderwrack, iris moss, greater celandine, elecampane, gravel root, wild yam, couchgrass, stinging nettle, pluerisy root, gum plant, wild cherry bark, apple ( fruit, bark, apple cider vinegar.)

Black walnut and elderflowers are also high in potassium.

Apple cider vinegar makes a very good all round tonic for regular use. Add 1-2 tablespoons in a glass of warm water and sweeten with honey.