dioxide. 14. Chlorine is rapildy absorbed by alcohol. [See
Alcohol, No. 5.] 15. Chlorine bleaches indigo, litmus, and
other organic colors. 16. It oxidizes nearly all organic matter.
Chromii Trioxidum, Chromic Acid. — i. Chromic
acid combines with the alkali hydroxides to form yellow nor-
mal chromates and red dichromates. 2. Chromic acid, or
chromates in solution with sidphuric acid, are reduced to chromic
salts by tartrates, producing formic acid, carbon dioxide, and
water; 3. by oxalates, forming carbon dioxide; 4. by hypo-
phosphites (no action in alkaline mixtures), forming phosphoric
acid; 5. by sulphides, liberating sidphiu:; 6. by sulphites,
forming sidphuric acid; 7. by chlorides, liberating chlorine;
8. by bromides, liberating bromine; 9. by iodides, liberat-
ing iodine; 10. by dilute alcohol, forming aldehyde, and
acetic acid. 11. Chromic acid, with strong alcohol, glyce-
rin, ether, volatile oils, or other readily oxidizable matter, is
liable to cause an explosion or fire. 12. The soluble chromates
and bichromates precipitate aqueous solutions of salts of lead,
silver, mercury, bismuth, manganese, barium, and
strontium as chromates, generally normal, varying in color
from yellow to red. 13. Potassium bichromate precipitates
many alkaloids from aqueous solutions of their salts, e.g., atro-
pine, codeine, hydrastine, quinine, strychnine, mor-
phine (only in concentrated solutions, i : 100). The normal
potassium chromate does not precipitate as many of the alkaloids
as the bichromate. 14. Bichromates are liable to cause an
explosion when triturated with tannic acid, sugar, or other
substances that are easily oxidized. 15. The chromates of the
alkalies, magnesium, calcium, and zinc are soluble in water; the
others are sparingly soluble. They are nearly insoluble in alcohol.



Digitized by



Google



64 INCOMPATIBILITIES IN PRESCRIPTIONS.

Chrysarobinum. — i. Yields chr3rsophamc acid on oxi-
dadoD. 2. Dissolves in aqueous solutions of the alkalies giving
a red liqmd with a greeni^ fluorescence. 3. Lime water ^ves
a violet color.

Cinchona*— I. Cinchona contains a sufficient amount of
tannic acid to make its preparations incompatible with many
metallic salts and other compounds. [See Acxdum Tannicum.]
2. The tannic acid gives a color varjdng from brown to blackish
green with solutions of ferric salts. 3. The cinchona alkaloids
in solution form compoimds with the general alkaloidal rea-
gents, which compounds are nearly insoluble in water but soluble
in alcohoL [See Alkaloids and Quinina.]

Citropheny Paraphenetidin Citrate, — i It gives a dark
red color with a solution of ferric chloride.

Cocaina. — i. Cocaine is precipitated from aqueous solu-
tions of its salts by the reagents that usually precipitate alka-
loids. [See Alkaloids, Nos. 2 and 3.] 2. Cocaine is quite
easily decomposed by strong acids, strong solutions of alkali
hydroxides, or by hot water, forming methyl alcohol, benzoic
add, and ecgonine. 3. Mixed with calomel in the presence
of moisture cocaine hydrochloride turns the mixture gray or
even black, due probably to the reduction of some of the calo-
mel to metallic mercury, while at the same time some mercuric
chloride is formed. The mercuric chloride then combines with
the alkaloid to form a compoimd insoluble in water. The free
alkaloid cocaine mixed with calomel does not readily darken,
but may be made to do so by blowing the fumes of hydrochloric
add over it. 4. A concentrated solution of cocaine hydrochlo-
ride is precipitated by a solution of chromic acid or potassium
permanganate.

Codeina* — i. Codeine in aqueous solution is not precipi-
tated by alkaline carbonates, bicarbonates, or ammom'um carbo-
nate, but is precipitated by most of the other alkaloidal
reagents. [See ALKALoms, Nos. 2 and 3.] 2. Codeine in
aqueous solution gives a precipitate with solutions of salts of
iron, lead, copper, and some other metals (N. D., 455). This



Digitized by



Google



INCOMPATIBILITIES IN PRESCRIPTIONS. 6$

is probably due to the fact that it is quite strongly alkaline and
one of the most soluble of the alkaloids. 3. With some am-
monium salts, as ammonium chloride, codeine liberates am-
monia. 4. If codeine is added to a solution of a morphine
salt morphine is set free and usually precipitated. 5. Nitric
acid gives a yellow solution with codeine.

Colchicina. — i. Colchicine is darkened by exposure to
light. 2. It is precipitated from aqueous solution by most of
the general alkaloidal reagents, imless the solution is quite
weak. 3. Colchicine is readily decomposed by strong acids or
strong solutions of alkalies, forming colchiceine. Acids gener-
ally give a yellow color. Nitric acid gives a blue to a violet
color turning brown and then yellow (Sohn, 42). Potassium
hydroxide gives a red color (N. S. D., 460). 4. Most of its
salts are decomposed by water (M. & M., n. 234.)

Collodiiun.— I. Collodion is geladnized by carbolic acid
and by a large excess of creosote. Alcohol renders the mass
more fluid. 2. Water separates the gun-cotton. [See Pyroxy-

UNUM.]

Conilna. — i. Coniine becomes yellow and resinoid on
keeping and gives off ammonia (U. S. D., 394). 2. It is not
precipitated by the alkali hydroxides or carbonates, but it is by
the general alkaloidal reagents, except platinic chloride.
[See AucALoms.] 3. Coniine coagulates albumin. 4. It pre-
cipitates solutions of salts of aluminum, copper, zinc, man-
ganese, iron, and silver; the precipitate with sflver is soluble
in excess of die alkaloid (U. S. D., 394). 5. It forms butyric
acid when treated with most oxidizing agents. 6. An alco-
holic solution of iodine with coniine gives a brown precipitate,
which afterwards disappears, and the liquid becomes colorless
(M. & M., n. 246). 7. Vapors of coniine coming in contact
with those of hydrochloric acid give white fumes.

Copaiba.— I. Copaiba, with the hydroxides of the alka-
lies or alkaline earths, forms saponaceous compounds, in
which the resm acts the part of an add. 2. With one sixteenth
of its weight of magnesia which has been dampened with water.



Digitized by



Google



66 INCOMPATIBILITIES IN PRESCRIPTIONS.

the resin of the copaiba combines slowly to form a solid mass.
A similar change is produced by calcium hydroxide (U. S. D.,

398).

Creosoti Carbonas, Creosolal. — i. Creosote carbonate
is decomposed by alkalies, liberating creosote.

Creosotnin. — i. Creosote reduces some of the inorganic
salts, such as salts of silver, gold, and copper, to the metallic
state. 2. If mixed suddenly or tritiu^ated dry with strong oxidiz-
ing agents it is liable to cause an explosion. 3. It precipi-
tates solutions of albumin and gma (not gelatin) (N. S. D.^
497). Creosote in large excess gelatinizes collodion. 4. Creo-
sote with solutions of ferric salts gives a violet-blue color,
changing to greenish brown, and, unless in very dilute solution,
a brown precipitate is formed. An alcoholic solution of creosote
with an alcoholic solution of ferric chloride gives a bluish-green
color (U. S. D., 404). s- Triturated with silver oxide, an
explosion is liable to take place. 6. With concentrated nitric
acid reddish fumes of the oxides of nitrogen are given off. With
dilute nitric acid a brown resin is formed (U. S. D., 404). 7.
With concentrated sulphuric acid it gives a red color, becoming
black on adding more acid. 8. Creosotie gives a white precipi-
tate with solution of lead subacetate. 9. Creosote dissolves a
large number of metallic salts and reduces some of them to the
metallic condition (U. S. D., 403).

Cresol.— I. Cresol dissolves in solutions of alkali hydrox-
ides. 2. A dilute solution with a solution of ferric chloride
gives a blue violet (N. S. D., 499).

Capri Sulphas. — i. Copper sulphate is precipitated by
the fixed alkali hydrates as blue copper hydrate, which on
standing becomes basic and black. This precipitation is more
or less prevented by citrates, tartrates, salicylates, sugar, milk
sugar, glycerin and other organic substances. A solution of
copper sulphate and acacia is gelatinized by the alkali hydrates.
2. Ammonia water precipitates the cupric hydrate and in
excess dissolves it, forming an intense blue solution. This
solution dissolves cotton, filter paper, and other forms of cellu-



Digitized by



Google



INCOMPATIBILITIES IN PRESCRIPTIONS. 6y

lose. 3. Ammonium carbonate, like ammonia water^ pre-
cipitates the copper and then redissolves it, forming a blue
solution. 4. The carbonates of the fixed alkalies precipi-
tate the copper as a basic carbonate of variable composition.
5. In neutral solutions the soluble phosphates give a blue-
white precipitate of copper phosphate. 6. Arsenites in
neutral solution give a green precipitate of copper arsenite.
7. Soluble iodides reduce and precipitate copper sulphate as
cuprous iodide (Cu J,), iodine being liberated. 8. In alkaline
mixtures cupric compounds are reduced to cuprous oxide
by arsenous add, glucose, and many organic substances.
9. Copper sulphate coagulates a solution of albumin.
ID. Tannic acid precipitates a solution of copper sulphate,
and with heat reduces the copper. 1 1 . Sodium salicylate
with copper sulphate in solution gives a green color, and the
copper is not precipitated from dilute solution by alkalies. 12.
Antipjrrine gives a green color to a solution of copper sulphate.

Decocta. — ^The incompatibilities of decoctions are similar
to those of infusions. [See Infusa.]

Digitalis. — I. Digitalin is precipitated from solutions by
tannic acid and chloride ofgold, not by most of the other
alkaloidal reagents (Sohn, 49). 2. With nitric acid digitalin
ffves at first a colorless solution, changing to yellow or green
(Sohn, 50). 3. Digitonin is precipitated from aqueous solution
by ammonia, tannic acid, or lead acetate (Sohn, 50). 4. All
of the principles of digitalis are quite easily decomposed by strong
acids or alkalies.

Dloretin. — i. Sodio-theobromine salicylate in aqueous so-
lution is strongly alkaline, and is decomposed by acids, even
the carbon dioxide m the air, with precipitation of probably both
theobromine and salicylic acid. 2. Alkali carbonates (not
hydroxides), sodium phosphate and borax slowly give pre-
cipitates. 3. Diuretin in excess gives precipitates with solutions
of many metallic salts. 4. With a solution of ferric chloride
it gives no precipitate but a violet to red color on account of the
salicylate. 5. It reduces salts of silver and mercury (ScovUley



Digitized by



Google



68 INCOMPATIBILITIES IN PRESCRIPTIONS.

297). Calomel is darkened at once by diuretin. 6. Tincture of
iodine is decolorized at first but added in excess it gives a pre-
cipitate. 7. It precipitates some alkaloids from solution of dieir
salts. 8. Rubbed with piperazine and some solids it gives a
mass or liquid. [See page 267.] 9. It has the incompatibilities
of a salicylate, theobromine, and an alkali.

Elaterinum. — i. Elaterin combines with the alkali hy-
droxides to form compoimds soluble in water, from which
solution acids precipitate the elaterin. 2. It is precipitated
from alcoholic solution by lead acetate and silver nitrate
(Watts, n. 373).

Emulsa* — Emulsions are broken up by substances which
precipitate the emulsifjring agent. [For emulsions made with
acacia, see Acacia].

Ergota. — ^The active principles of ergot are generally pre-
cipitated by tannic acid, metallic salts, potassium mercuric
iodide, and some of the general alkaloidal reagents.

Erythrol Tetraiiitrate* — i. Erydirol tetranitrate is de-
composed by warmth and sunlight tiuning yellow and giving
off nitrous fumes (U, S. D., 1480). 2. Triturated with glucose
it has caused explosion.

Eucalna. — i. Eucaine hydrochloride A in solution is pre-
cipitated by alkali hydroxides, carbonates, potassium per-
manganate, mercuric chloride and potassium iodide, and
it is colored red by ferric chloride (N. S. D., 578). 2. Eucaine
hydrochloride B in solution is precipitated by alkalies and their
carbonates, but not by mercuric chloride from a five per cent,
solution (N. S. D., 578).

Eucalyptol. — Eucalyptol is oxidized to cineolic acid by
potassium permanganate (M. & M., n. 526). 2. Iodine in
potassium iodide gives green crystals; bromine gives red crystals;
naphthol gives addition products (N. S. D., 580).

Euphorin, Phenyl urethane. — i. Euphorin gives a mass
or liquid when tritiurated with hedonal, trional and many
other solids. [See page 267.]

Europhen, IsobtdyUarthocresol Iodide. — i. Eiux>phen is



Digitized by



Google



INCOMPATIBILITIES IN PRESCRIPTIONS. O9

soluble in alcohol, ether, and fixed oils. 2. Heat and light
tend to liberate iodine, partiailarly in solution. 3. The solution
in oil is of doubtful efficiency, since the iodine slowly liberated
combines with the oiL 4. It is not advisable to prescribe it
with substances that have a strong affinity for iodine, as oxides,
hydroxides, starch, salts of mercury. 5. An alcoholic solution
gives a yellow, flocculent precipitate with mercuric chloride.

Exalgina, Methyl Acetanilide. — i. Exalgine liquefies or
gives a mass when triturated with many solids. [See page
267.1

Ferripyrlne.— I. Light decomposes ferripyrine. 2. Alkali
hydroxides, carbonates, and bicarbonates precipitate ferric
hydroxide from aqueous solutions (N. S. D., 195).

Ferri Phosphas Solubilis.— i. The soluble phosphate
of iron, being made by mixing solutions of ferric citrate and
sodiimi phosphate, is perhaps a mixtxire of ferric phosphate
and sodium citrate, or it b more probably a sodio-ferric citro-
phosphate. When a dilute mineral acid other than meta-
phosphoric acid is added the sodium citrate or the sodio-ferric
dtro-phosphate is broken up and the ferric phosphate is pre-
cipitated. Strong mineral acids may redissolve the precipitate.
Metaphosphoric (glacial phosphoric) acid free from ortho-
phosphoric acid does not cause precipitation. 2. In aqueous
solution the soluble phosphate of iron is precipitated by sodium
or potassium hydroxide as ferric hydroxide. Ammonium
hydroxide gives a reddish color, but no precipitate. [See Fer*
BicuM and Acmuii Phosphosicum.]

Ferri Pyrophosphas Solubilis. — i. The soluble pyro-
phosphate of iron is a mixture or compound similar to the soluble
phosphate of iron, and on adding a dilute mineral acid the
ferric pyrophosphate is thrown out of solution. Strong solutions
of mineral acids may redissolve the precipitate. Metaphos-
phoric acid free from orthophosphoric acid does not cause pre-
cipitation. 2. The red-brown ferric hydroxide is precipitated
from aqueous solutions by potassium or sodium hydroxide.
3. Ammonium hydroxide turns the solution red, but does not



Digitized by



Google



70 INCOMPATIBILITIES IN PRESCRIPTIONS.

cause precipitation. [See Fessicum and pyrophosphoric acid
under Acidum Phosphoricum.]

Ferricum. — i. Ferric salts are precipitated from their
aqueous solutions by the alkali hydroxides and carbonates as
the red-brown ferric hydroxide. This precipitation is more or
less prevented by the presence of sugar, glycerin, citrates, tar-
trates, and other organic compoimds. 2. When the insoluble
carbonates of barium, calcium, magnesium, and copper are
added to solution of ferric salts the ferric hydroxide is precip-
itated, the base added combining with the acid of the ferric
salt. 3. Borax with solutions of ferric salts gives an insoluble
basic borate (Wattis, i. 530). Sugar, glycerin, citrates, and
tartrates prevent or retard precipitation. 4. Solutions of the
alkali phosphates precipitate iErom neutral solutions of ferric
salts the white ferric phosphate, the precipitation being pre-
vented by citrates, tartrates, and considerable excess of free
acids. 5. The alkali sulphides precipitate the black ferrous
sulphide after reducing the ferric compoimds to ferrous and liber-
ating sulphur. Hydrogen sulphide reduces ferric to ferrous and
liberates sulphur, but causes no precipitation of iron. 6. Soluble
cyanides precipitate the neutral solutions of ferric salts as ferric
hydroxide with evolution of hydrocyanic acid. 7. Ferrocyanides
with ferric salts give the blue precipitate of ferric ferrocyanide
(Prussian blue) ; this is prevented to some extent by citrates
in neutral solutions. 8. Ferricyanides give a brown solu-
tion with ferric salts. 9. With solutions of ferric salts sul-
phites give a red solution of ferric sulphate, which changes
on heating or standing to ferrous sulphate and the solution
becomes nearly colorless. 10. Phosphoric acid in excess
decolorizes a solution of ferric chloride by forming the color-
less ferric phosphate. 11. In neutral solutions the alkali
hypophosphites precipitate ferric salts as ferric hypophos-
phite, but in acid solutions the iron is reduced to the ferrous
condition and the hypophosphite is oxidized to a phosphate.
12. Hydriodic acid and soluble iodides with a mineral acid
reduce ferric compounds to ferrous, iodine being liberated



Digitized by



Google



INCOMPATIBILITIES IN PRESCRIPTIONS. ^l

and precipitated if the iodide is entirely decomposed. 13,
Arsenites give precipitates of basic ferric arsenite with solu-
tions of ferric salts if they are not too strongly acid. The basic
ferric arsenite is changed to some extent to a ferrous arsenate (P. &
J., 62.) Arsenates give the msoluble ferric arsenate. 14. The
official tannic acid gives a blue-black solution or precipitate of
ferric tannate. Phosphoric acid in excess destroys the color by
breaking up the compound and forming the colorless ferric phos-
phate. Some tannic acids give a green-black color. With the ex-
ception of gentian, quassia, columbo, American columbo, chiretta,
and canella nearly all drugs contain tannin. 15. Gallic acid gives
a blue-black color with a solution of ferric chloride. [See
AciDUM Gallicum, No. 7.] 16. Acetateis give a deep dull
red liquid with nearly neutral solutions of ferric salts, due to
the formation of ferric acetate. This solution on heating
throws down a precipitate of basic ferric acetate. Acetic
acid does not increase the color of a solution of ferric chloride
unless the iron solution is quite highly diluted. 17. Soluble
benzoates precipitate nearly neutral solutions of ferric salts
as ferric benzoate which is flesh-colored. The presence of an
excess of free acid or of alkali tartrate interferes or prevents
the precipitation. 18. With solutions of the salicylates fer-
ric salts give a blue-violet to violet-red solution ; the color is
destroyed by a large excess of a mineral acid. In concen-
trated or neutral solutions ferric salicylate may be precipi-
tated. 19. Carbolic add with concentrated solutions of
ferric chloride gives but little increase in color. On diluting
with water the solution becomes green and more water
changes it to violet blue. 20. In dilute aqueous solutions
creosote or guaiacol gives with ferric chloride a violet-blue
color which soon changes to green brown. An alcoholic
solution of ferric chloride with creosote gives blue green. 21.
Acetanilide with an alcoholic solution of ferric chloride gives
a red color. With an aqueous solution it gives no color
unless heated, and then the color fades on cooling. If the
solution is heated for several minutes the color is changed to



Digitized by



Google



72 INCOMPATIBILITIES IN PRESCRIPTIONS.

a permanent green. 22. Antipyrine gives a red color with a
solution of a ferric salt [See Antepykina, No. 3.] 23.
Phenacetin with a tincture of ferric chloride gives a deep
red solution. 24. With pjrrocatechin a solution of ferric
chloride gives a green color; 25. with pjrrogallol it gives a
red; 26. and with resorciny a violet 27. An alcoholic solu*
tion of salol gives a violet to red color with a tincture of iron,
but when sufficient water is added the color is destroyed and the
salol precipitated. 28. Piperazine gives a red-brown precipitate.
29. Oil of wintergreen gives a violet color with an alcoholic
solution of ferric cUoride; 30. oils of cloves, bay, and pimenta
give a blue to a green; 31. oil of cinnamon gives a brown;
32. oil of thyme gives a green brown, changing to red. 33. An
alcoholic solution of ferric chloride gives a dark brown-green color
with podophyllin; 34- with aloin it gives a green black to a
brown black; 35. with benzoin, a brown to green; 36. with
gamboge, a black brown; 37. with asafoetida or storax, a
green brown; 38. with mjrrrh, a red brown; 39. with g^aiac*
a blue to brown; 4a with balsam of Peru, a green black;
41. with balsam of Tolu, a brown; 42. and with shellac, a
black. 43. With a nearly neutral aqueous solution of ferric
chloride morphine gives a blue to green solution, and with
apomorphine it gives a red changing to a black. 44. Solutions
of ferric salts gelatinize mucilage of acacia. [See Acacia, No. 2.]
45. They cos^ulate solutions of albumin. 46. Glycerin and
syrup give a darker color due to hydrolysis into ferric hydroxide
and hydrochloric acid (BuL Pharm., xix. 389.)

Ferrostun.— I. Ferrous salts are quite quickly chang^
to basic ferric compounds on being exposed to the air.
Sugar, glycerin, and organic matter in general retard the
oxidation. 2. Ferrous salts in aqueous solution are precipi-
tated to some extent by the alkali hydroxides as the white
ferrous hydrate, quickly changing to the ferroso-ferric hydrate,
which is of a dirty green to a black color. This precipitate
ultimately oxidizes to a ferric hydroxide or oxide, .^nmonium
chloride of sulphate, soluble citrates or tartrates, sugar^



Digitized by



Google



2NC0MPATIBIUTIBS IN PRESCRIPTIONS. 73

glycerin and many oi^nic compounds, dissolve the ferrous
hydrate or prevent the precipitation. 3. The soluble carbon-
ates precipitate the ferrous carbonate, white if purely ferrous,
but quickly becoming green and ultimately brown, due to the
formation of a ferric compound. 4. The soluble phosphates
precipitate the white or bluish-white ferrous phosphate.
5. With nearly neutral solutions borax gives a white pre-
cipitate. 6. The soluble sulphides (not hydrogen sulphide)
precipitate the black ferrous sulphide. 7. Ferrocyanides
precipitate the light blue ferrous ferrocyanide. 8. Ferricy-
anides precipitate the dark blue ferrous ferricyanide. 9. Arsen-
ites and arsenates give precipitates with solutions of ferrous salts
(P. & J., 158). 10. Tannic acid with strong solutions of ferrous
salts precipitates the white gelatinous ferrous tannate. This
quickly oxidizes, forming the nearly black ferric tannate. Ferrous
salts usuaQy contain enough of a ferric salt to give the dark color at
once. !!• Gallic acid with a concentrated solution of a ferrous
salt gives a white precipitate which soon turns dark, due to the
oxidation of the iron and formation of the ferric gallate.
12, Ferrous salts in solution are oxidized to ferric compounds
by salts of gold or silver, by hydrogen dioxide, chromates,
permanganates, nitrous or nitric acid, chlorine or chlorates
in acid solution, bromine or bromates in acid solution,
iodates in acid mixture, mercuric compounds in alkaline mix-
ture, arsenates in alkaline mixtures, and by oxygen of the
air. 13. The alkaline citrates in solution modify the astrin-
gent effects of ferrous salts, and dissolve many of the salts
not soluble in water.

Ferrum Beductum. — i. Reduced iron combines with
acids to form salts. 2. It is oxidized by moist air. 3. In
the presence of water it reduces to the metallic condition salts
of copper, bismuth, lead, silver, mercury, and antimony. 4.
Triturated dry with strong oxidizing agents, such as potas-
sium permanganate or potassium chlorate, it is liable to
cause an explosion. 5. In the presence of water iron forms
ferrous iodide with iodine, and ferrous bromide with bromine.



Digitized by



Google



74 INCOMPATIBILITIES IN PRESCRIPTIONS.

6. Iron is slowly oxidized to a hydroxide by hydrogen dioxide
water.

Fluidextracti. — i. Fluidextracts are generally more or less
acid and liberate carbon dioxide from carbonates. 2. Water
causes precipitation of inert matter and sometimes active principles.

G^latinum. — i. Solutions of gelatin are coagulated by
tannic add, picric add, metaphosphoric acid, chlorine
water, mercuric chloride, platinum chloride, alumnol,
alcohol, or formaldehyde. Aqueous solutions are not pre-
cipitated by alum, lead acetate, ferric chloride, dilute acids,
or dilute alkalies (N. S. D., 710). 2. Heating an aqueous solu-
tion of gelatin for some tune renders it incapable of gelatinizing.

61acosid.es. — i. Glucosides are decomposed by pro-