Latinizing a prescription correctly requires a very limited knowledge of the Latin language, yet that little is too often absent from the education of would-be doctors of medicine. Within the small place which can be allotted to this portion of the subject in these pages, it is impossible to offer more than a few notes to guide the student at first. For full treatment of the subject the reader is referred to Pareira's Prescription Book, which deals fully with every detail.

Table of Genitive Case-Endings.

a ae Cataplasma, Enema, Physostigma, Aspidosperma and Gargarysina, all have the genitive in -atis. Coca(*) is unchanged. Folia is plural, gen. Foliorum.
i Rhus, Rhois; Flos, Floris; Bos, Bovis; Limon, Limonis; Erigeron, -ontis.

Fructus, Cornus, Quercus, Spiritus, Haustus, Potus, do not change.

as atis Asclepias, adis; Mas, Maris.
is idis Pulvis, -eris; Arsenis, -itis, Phosphis, -itis, Sulphis, -itis, and all salts ending in -is, having genitive in -itis.
o onis Mucilago, -inis; Ustilago, -inis; Solidago, -inis.
l lis Fel, Fellis; Melt, Mellis; Sumbul, Sumbuli.
Words which do not change in the Genitive.
*Amyl. Azedarach. Berberis. Buchu. Cannabis. Catechu. Coca.(*) Cundurango. Cornus. Curare. Digitalis. Fructus. Haustus. Hydrastis. Jaborandi. Kino. Matico. Potus. Quercus. Sassafras. Sago. Sinapis. Spiritus.

*Amylis, is given. (*) Cocae, is given.


The Verbs used in prescription-writing are nearly all in the imperative mood, giving directions to the compounder, and having their object in the accusative case. Such are—
Adde, add.
Cola, strain.
Divide, divide.
Extende, spread.
Fac, make.
Filtra, filter.
Macera, macerate.
Misce, mix.
Recipe, take.
Signa, write.
Solve, dissolve.
Tere, rub.
A few verbs are found in the subjunctive mood, taking their subject or predicate in the nominative case. The most usual are—
Fiat, let be made.
Fiant, let be made.
Coletur, let be strained.
Coloretur, let be colored.
Sumatur, let be taken.
Bulliat, let boil.
Capiat, let take.
Detur, let be given.
Dividatur, let be divided.
Sit, let it be.


Participles or Verbal Adjectives are occasionally used, and should agree with their respective nouns in gender, number and case. Such are the following, viz.:—
Dividendus, -a, -um, to be divided.
Sumendus, -a, -um, to be taken.
Adhibendus, -a, -um, to be administered.


Those in the first column require the noun following to be in the accusative case,—those in the second column require the ablative case.

Ad, to, up to.
In, into.
Supra, upon.
Cum, with.
Pro, for.
Sine, without.
Ana, of each,—governs the genitive case.

Sundry Words and Phrases, in Most Frequent Use.

Ad saturandum, to saturation.
Bene, well.
Bis, twice
Da, give.
Dein, thereupon.
Et, and.
Gradatim, gradually.
Guttatim, by drops.
In dies, daily.
In partes aequales, into equal parts.
Non Repetatur, let it not be repeated.
Non, not.
Numero, to the number of.
Numerus, number.
Octarius, a pint.
Pro re natâ, according to need.
Quantum sufficiat, as much as necessary.
Quater, four times.
Redactus in pulverem, let be pulverized.
Secundum artem, according to art.
Semel, once.
Simul, together.
Statim, at once.
Ter, thrice.

Abbreviations are in general use in prescription writing, but should be avoided as much as possible. Their lavish use is a sign of the prescriber's ignorance of Latin, they confound the compounder, enhance the chances for error, and are therefore a frequent source of danger to the patient. In the larger works on pharmacy, very full lists of the commonly used abbreviations are given. The following table gives a few examples of the dangers of carelessness in their employment.

Aconit.—may mean either Aconitum or Aconitina.
Ammon.—Ammonia or Ammoniacum.
Ac. Hydroc.—Acidum Hydrochloricum or Acidum Hydrocyanicum.
Aq. Font.—might easily be read Aqua Fortis.
Chlor.—Chlorum, Chloral, or Chloroformum.
Hyd. Chlor.—Hydrate of Chloral, Hydrargyri Chloridum.
Sulph.—Sulphur, Sulphas, Sulphidum, Sulphitum.
Zinc. Phos.—Zinci Phosphas or Zinci Phosphidum.

A Compend of Materia Medica, Therapeutics, and Prescription Writing, 1902, by Sam'l O. L. Potter, M.D., M.R.C.P.L.