Scruple (s ap)
The scruple is an apothecaries' unit of mass equal to 20 grains or approximately 1.296 grams. Once a standard unit in pharmacy for measuring drug ingredients, the scruple was rendered obsolete by the adoption of the metric system in medicine. The word "scruple" in the sense of a moral hesitation derives from the same Latin root, scrupulus (a small sharp stone).
Definition
One scruple equals exactly 20 grains, 1/3 of an apothecaries' dram, 1/24 of an apothecaries' ounce, approximately 1.296 grams, or 1,296 milligrams. The scruple is part of the apothecaries' weight system and has no equivalent in the avoirdupois system.
History
The scruple comes from the Latin scrupulus, a small unit of weight in Roman measurement. In the apothecaries' system, 3 scruples made one dram and 24 scruples made one apothecaries' ounce. For centuries, pharmacists measured drug ingredients in scruples, drams, and grains. The shift to metric measurement in pharmacy began in the 19th century and was largely complete by the mid-20th century. The US Pharmacopeia dropped apothecaries' units in 1971. Today, the scruple exists only in historical pharmacy records and in the English language as a metaphor for smallness.
Common Uses
The scruple has no modern applications. It appears only in historical pharmacy records, antique pharmaceutical equipment, and as a topic in the history of medicine. Understanding scruples is necessary for interpreting pre-metric prescription records and pharmaceutical texts.
Did You Know? Facts About Scruple
- The English word "scrupulous" (meaning careful and thorough) comes from the same Latin root as the unit - scrupulus meant a small sharp stone that could cause discomfort.
- The US Pharmacopeia officially dropped the scruple and all apothecaries' units in 1971.
- One scruple equals exactly 20 grains - so a 5-grain aspirin tablet is exactly one-quarter of a scruple.
- Three scruples make one dram, and eight drams make one apothecaries' ounce.
- The symbol for scruple (℈) is a Unicode character that looks like a reversed script E.