In the Latin of a prescription the following rules govern the case:

1. The noun expressing the name of the medicine takes the genitive when the quantity to be used is stated.

2. The noun expressing the name of the medicine takes the accusative when the number of pills or troches, etc., already prepared, is stated.

3. The quantity of the drug used, if written in Latin instead of figures, would be in the accusative governed by the imperative verb recipe.

4. Adjectives agree with their nouns in gender, number and case.

The Declension of Pharmacopoeial Latin Nouns.

First Declension

Nouns ending in a belong to the first declension, are feminine, and have their genitives in oe. The exceptions to this rule are:

Nominative

Genitive

Third declension, neuter gender

Enema

Enematis

Physostigma

Physostigmatis

Aspidosperma

Aspidospermatis

Folia (pleural)

Foliorum

Second declension, neuter gender

Second Declension

Nouns ending in er, ir, us, and os are masculine and have their genitives in i.

Nouns ending in um, and one in on (Haematoxylon), are neuter and have their genitives in i.

The exceptions to this rule are:

Nominative

Genitive

Aether

Aetheris

Third deelension,masculine

Bos

Bovis

Flos

Floris

Rhus

Rhois

Quereus

Quercus

Fourth declension, feminine

Spiritus

Spiritus

Fourth declension, masculine.

Third Declension

A large number of pharmacopoeial nouns belong to this declension, and may be masculine, feminine, or neuter in gender. They have quite dissimilar endings, and the genitives depend upon these endings, consequently it is difficult to formulate rules. Therefore the drugs of this declension are arranged alpha betically with their genitives and genders following them.

Nominative

Genitive

Gender

Acetas

Acetatis

m

Adeps

Adipis

m

Aether

Aetheris

m

Aethyl

Aethylis

n

Alcohol

Alcoholis

n

Alumen

Aluminis

n

Amyl

Amylis

n

Anthemis

Anthemidis

f

Arsenas

Arsenatis

m

Arsenis

Arsenitis

m

Asclepias

Asclepiadis

f

Aspidosperma

Aspidospermatis

n

Benzoas

Benzoatis

m

Berberis

Berberidis

f

Betanaphthol

Betanaphtholis

n

Boras

Boratis

m

Bos

Bovis

m

Calx

Calcis

f

Cannabis

Cannabis

f

Cantharis

Cantharidis

f

Carbamas

Carbamatis

m

Carbo

Carbon is

m

Carbonas

Carbonatis

m

Chloras

Chloratis

m

Chromas

Chromatis

m

Citras

Citratis

m

Colocynthis

Colocynthidis

f

Confectio

Confectionis

f

Nominative

Genitive

Gender

Cortex

Corticis

m

Cresol

Cresolis

n

Digitalis

Digitalis

f

Elixir

Elixiris

n

Enema

Enematis

n

Erigeron

Frigerontis

m

Eucalyptol

Eucalyptolis

n

Eugenol

Eugenolis

n

Fel

Fellis

n

Flos

Floris

m

Gallas

Gallatis

m

Glyceryl

Glyceryl is

n

Guaiacol

Guaiacolis

n

Hamamelis

Hamamelidis

f

Hydrastis

Hydrastis

f

Lactas

Lactatis

m

Limo

Limonis

m

Liquor

Liquoris

m

Mel

Mellis

n

Menthol

Mentholis

n

Methyl

Methyl is

n

Mucilago

Mucilaginis

f

Nitras

Nit ratis

m

Nitris

Nitritis

m

Nux

Nucis

f

Oxalas

Oxalatis

m

Pepo

Peponis

m

Permanganas

Permanganatis

m

Phenol

Phenol is

n

Phenyl

Phenylis

n

Phosphas

Phosphatis

m

Phosphis

Phosphitis

m

Physostigma

Physostigmatis

n

Piper

Piperis

n

Pix

Picis

f

Pulvis

Pulveris

m

Pyrogallol

Pyrogallolis

n

Radix

Radicis

f

Resorcinol

Resorcinolis

n

Rhus

Rhois

m

Salicylas

Salicylatis

m

Sapo

Saponis

m

Semen

Seminis

n

Sinapis

Sinapis

f

Stearas

Stearatis

m

Styrax

Styracis

m

Sulphas

Sulphatis

m

Sulphis

Sulphitis

m

Sulphur

Sulphuris

a

Nominative

Genitive

Gender

Tannas

Tannatis

m

Tartras

Tartratis

m

Theobroma

Theobromatis

f

Thymol

Tliymolis

n

Trituratio

Triturationis

f

Valeras

Valeratis

m

Zingiber

Zingiberis

n

Fourth Declension

The following nouns ending in us have their genitives in us:

Nominative

Genitive

Gender

Quercus

Quercus

f

Spiritus

Spiritus

m