Dear S.,
I am sure some Mom's are going to disagree strongly with what I do for my children but it works for us with minimal harm.
Both of my children have had leg/growing pains and we administer medicine and give massage until they are able to sleep. my husband and I both remember these pains from our childhood.
And both of my children have requested "medicine" when I know they are not in pain. How do I know? My children's real pain would awake them in the middle of the night or be right at the start of bedtime after a very busy day of physical activity. "Fake" pain would be a sibling's cry for medicine of "me too, me too, i need medicine, Oh I hurt too" or after a day or two of leg pains. So I took an old children's liquid medicine bottle, washed it clean, put a new label over it that i had written "tummy & leg medicine", put water in with a splash of motrin to flavor. My children got this when I felt that true pain relievers were not required. It negated tantrums, didn't taste as "good" as true medicine, and answered their needs.
Just what our family does. Good luck.