For teens and adults, I give 1-2 peppermint and 1-2 ginger pills based on the size of the person and the severity of the pain. It works.
For a child that can't swallow pills or doesn't like the taste of ginger and peppermint teas, I give Hylands #10 homeopathic pills which are very tiny and dissolve almost instantly in the mouth with no bad taste. Both my younger children are prone to stomachaches and they both swear by these pills. I don`t know if it is just a placebo effect or if there really is something to homeopathy, but for my children these do work for general stomachaches, there are no side effects, and I feel they are safe for young children. I have never had any problems, there's no choking hazards because they are so small and dissolve so quickly, and my children take these willingly.