Medical Definition of q_h (on prescription)
q_h (on prescription): If a medicine is to be taken every so- many hours, it is written "q_h"; the "q" standing for the Latin word for once "quaque" and the "h" indicating the number of hours. So, for example, "2 caps q4h" means "Take 2 capsules every 4 hours." However it is written, it is one of a number of hallowed abbreviations of Latin terms that have been traditionally used in prescriptions to specify the frequency with which medicines should be taken.
Other examples include:
Last Editorial Review: 6/9/2016
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