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From the wrong drug prescribed to the wrong dosage or administration schedule advised, dispensed, or administered, the impact of medication misadventures is a costly problem. Errors of these sorts occur because human beings are involved, and such errors can be prevented only by systems that make it difficult to do the wrong thing. This appendix provides a primer on the proper approach to the medication prescription and order process and a resource for practitioners in effectively providing pharmaceutical care for their patients.
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THE MECH ANICS OF PRESCRIPTION ORDER WRITING
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Early medicines were made up of multiple ingredients requiring complex preparation, and Latin was adopted as the standard language of the prescription to ensure understanding between physician and pharmacist and consistency in pharmaceutical composition. Latin no longer is the international language of medicine, but a number of commonly used abbreviations derive from old Latin usage. The symbol "Rx" is said to be an abbreviation for the Latin word recipere, meaning "take" or "take thus," as a direction to a pharmacist, preceding the physician's "recipe" for preparing a medication. The abbreviation "Sig" for the Latin Signatura, is used on the prescription to mark the directions for administration of the medication.
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The prescription consists of the superscription, the inscription, the subscription, the signa, and the name and signature of the prescriber, all contained on a single form (Figure AI–1).
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The superscription includes the date the prescription order is written; the name, address, weight, and age of the patient; and the Rx (Take). The body of the prescription, or inscription, contains the name and amount or strength of the drug to be dispensed, or the name and strength of each ingredient to be compounded. The subscription is the instruction to the pharmacist, usually consisting of a ...