your question is a complex one. suffice it to say, that ingesting free calcium ions, such as in so-called "calcium hydroxide drinks" modulates substance P and provides a short-term reduction in pain that gives the user a sensation of relief. Although an extreme viewpoint, it is similar to smoking crack. (when I was younger, "crack" had a different meaning. I refer to the modern definition)
Keep in mind also that free calcium ions do not occur naturally in foods & only in average waters to the extent of about 120 ppm. As always, there are exceptions to such a statement.