Abbreviating Latin expressions
Abbreviate Latin expressions of time and use periods. Use all lower case.
q.h.
q.i.d.
t.i.d.
When the Latin expression includes a number, the number is followed by a space but no period unless it is the end of the sentence.
q.4 h.
The lower case abbreviation for the Latin hora (hour) and die (day) are preferred to the SI abbreviation of lowercase h (hour) and d (day) without periods.
Do not capitalize abbreviations derived from Latin terms. The use of periods within or at the end of Latin abbreviations is the preferred style, although it is also acceptable to drop the periods for general Latin terms.
e.g. Latin: exempli gratia English: for example
et al. Latin: et alii English: and others
etc. Latin: et cetera English: and so forth
Latin abbreviations relating to doses and dosages
Use lowercase abbreviations with periods. Avoid using all caps; they emphasize the abbreviation, rather than the drug name. Avoid lowercase abbreviations without periods because they may be misread. Do not translate the abbreviated form of the dosage.
a.c. NOT AC or ac
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