Doctors often use Latin terms when they write prescriptions, but these terms usually have a simple English equivalent. You must know the proper instructions for taking medication in order to use it correctly and effectively. It's not difficult to find out the meaning by asking your doctor or simply looking up a term like PRN. Your pharmacist can also explain it if it's written on a prescription, and he can give you directions for using the medication properly to treat your condition.
PRN is an abbreviation that comes from the Latin term "pro re nata." Its actual translation to English is "for the thing born," but its common medical meaning is "as needed." It used to identify a medication that can be taken as the patient needs it rather than on a fixed schedule.
The most common types of PRN medications are those that treat occasional conditions. These include drugs to control pain, sleeping pills, anticongestants, cough medicine and medications that treat occasional stomach distress. They are usually used to treat acute conditions, which come up suddenly and are short-lived, rather than chronic diseases that need a regular treatment regime.
Many PRN medications can be purchased over-the-counter, and some are available only by prescription. The instructions for over-the-counter PRN medications should be clearly printed on the box or bottle or included on a package insert. When a doctor prescribes PRN medication, the instructions will be printed on the bottle and included on a patient information sheet.
Even though a PRN medication can be taken as needed, there are limitations on the amount you can take at one time and the number of doses you can safely take over the course of a day. For over-the-counter PRN medications, this information will be included on the bottle or in the package. For prescription PRN medications, your doctor will let you know how to use the drug properly.
Some PRN medications, such as pain killers and sleep aids, carry a risk of addiction. If you use them too often or over a long period of time, you can become dependent on them. If you believe this may be happening to you and you are unable to cut back your use of the medication, talk to your doctor about a withdrawal plan. She may also be able to give you a nonaddictive alternative.