A composition comprising at least one substance coated with an agent wherein the agent forms a liquid impermeable but gas permeable layer surrounding the said substance and preventing the passage of the said substance through said coating, wherein in-use the said substance is not released into solution in the body, and wherein said substance is selected from one or more of the group consisting of calcium phosphate, sodium chloride, potassium chloride, magnesium chloride, calcium carbonate, and sodium bicarbonate for use in the treatment of osteoporosis and other bone conditions.
