My Quora Answer to:
If a prescription says take three times a day. does it mean 3 times in 12 or 24 hrs?
Carmel Maalouf is correct. TID means three times a day, essentially in 24 hours. If I wanted a med taken evenly spaced out over that time, I would write “every 8 hours.” My decision which to write depended on the efficacy and half-life of that particular medication. If the half-life, basically the amount of time it is effective in your system, is around 8 hours, then I would write it that way. If much longer, but less than 12 hours, I would write TID. Why 12 hours? Because then I would go for twice a day (BID), or “every 12 hours.”
FYI: the medical abbreviation for “every” is a q/Q with a line over it. Many hospital systems no longer allow their docs to use it because it makes the administrators cry.
