William Hale-White.

Materia medica, pharmacy, pharmacology and therapeutics online

. (page 9 of 67)
Online LibraryWilliam Hale-WhiteMateria medica, pharmacy, pharmacology and therapeutics → online text (page 9 of 67)
Font size
QR-code for this ebook


Therapeutics. It is very rarely that we can do any good
in spinal diseases by attempting to stimulate the anterior cornua ;
but strychnine is occasionally given for cases of paralysis due to
diseases of the spinal cord.

Drugs which depress the activity of the anterior cornua :



(1) Physostigmine.

(2) Bromides.

(3) Alcohol.

(4) Chloroform.

(5) Ether.

(6) Ergot.

(7) Opium.

(8) Mercury.

(9) Zinc salts.
(10) Silver salts.

ii Sodium salts.

(12) Potassium salts.

(13) Lithium salts.

(14) Antimony salts.



(15) Arsenical salts.

(16) Camphor.

(17) Amyl nitrite.

(1 8) Sodium nitrite.

(19) Chloral [hydrate.]

(20) Carbolic acid.

(21) Apomorphine.

(22) Veratrine.

(23) Turpentine.

(24) Saponin.

(25) Emetine.

(26) Gelsemium.

(27) Colchicum.



Of these, apomorphine, alcohol, chloroform, ether, arsenic, camphor, mor-
phine, carbolic acid, chloral [hydrate,] nicotine, and veratrine first excite
slightly before depressing.

Therapeutics. These drugs are of very little use in medi-
cine for their action on the spinal cord. Physostigmine is by
far the most powerful, and has been occasionally used in obscure
nervous diseases accompanied by convulsions, as tetanus.

Ergot has a very peculiar action in producing sclerosis of the



1O4 PHARMACOLOGY AND THERAPEUTICS.

posterior columns of the cord. Lead sometimes causes atrophy
of the anterior cornual cells, and long-continued abuse of alcohol
probably causes slight degeneration of the cord as a whole.

F. Drugs act-ing on the Brain. The action of these can-
not be localized nearly so accurately as can that of drugs acting
on the spinal cord and nerves. Drugs acting on the brain illus-
trate two very important general laws.

First, the law of dissolution, which, when stated as it
applies in pharmacology, is as follows: When a drug affects
functions progressively, those first affected are the highest in
development ; that is to say, they are the last acquired by the
individual and the last to appear in the species. The next af-
fected are those next to highest, and so on ; till finally the lowest
of all from an evolutionary point of view, that is to say, the
functions of respiration and circulation, are affected. This law
is very well exemplified in the case of alcohol, for the first func-
tions to be disordered are those of the intellect, especially the
highest, such as judgment and reason ; then follow disorders of
movement, and finally death from failure of respiration and
circulation.

Another law very well exemplified by drugs which act on
the brain is that when a drug in moderate doses excites a func-
tion, in large doses it often paralyzes it. For example, a person
under the influence of chloroform, soon after its administration,
tosses his arms about in a disorderly way, but they subsequently
become motionless, and cerebral stimulants may also be hyp-
notics.

Drugs acting on the motor centres of the brain. To investigate
these, the motor area of the cortex is exposed by trephining, and
the strength of current which it is necessary to apply to the motor
area to produce corresponding movements, is noted before and
after the administration of the drug. Another method is to
observe the strength of current necessary to evoke a movement,
then to allow the wound [made by the trephine] to close, after-
wards the animal is made to take the drug regularly for some
weeks. The opposite motor area is then exposed, and the strength
of current required to call forth movements is noted.



DRUGS ACTING ON NERVOUS AND MUSCULAR SYSTEMS. IC>5

It has been found that [the following] diminish the activity of the motor
area.



(1) Alcohol.

(2) Anaesthetics.

(3) Chloral [hydrate.]



(4) Potassium bromide.

(5) Sodium bromide.

(6) Ammonium bromide.



Bromides are largely used in epilepsy and other convulsive
disorders on account of this function.

Drugs exciting the motor cells of the cortex are



(1) Atropine.

(2) Absinthium.



(3) Strychnine.

(4) Physostigmine.



They have no therapeutical application in virtue of this property.

General cerebral stimulants. It is impossible to know any-
thing of these by experiments on animals. In man they cause
general excitation of the mental faculties, followed in many cases
by delirium and incoherence. The exact form of delirium differs
a little in each case.



Such drugs are

(1) Belladonna.

(2) Stramonium.

(3) Hyoscyamus.

(4) Alcohol.

(5) Chloroform.

(6) Ether.

(7) Nitrous oxide.

(8) Coffee.

(9) Tea.
(10) Guarana.



(11) Coca.

(12) Cannabis Indica.

(13) Lupulus.

(14) Opium.

(15) Camphor.

(1 6) Santonin.

(17) Quinine.

(18) Salicylic acid.

(19) Tobacco.



Therapeutics. Many of these are taken habitually as cere-
bral stimulants ; for example, alcohol, tea, coffee, tobacco, in
England ; opium in the East ; cannabis indica in many parts of
Asia ; coca in parts of South America ; and if it is wished to
give a cerebral stimulant as a drug, one of these is usually chosen.
The rest, which are very important, are commonly employed for
some other action. With very many of this class of drugs, as
will be seen directly, the stimulant action soon gives way to a
paralyzing influence.



IO6 PHARMACOLOGY AND THERAPEUTICS.

General cerebral depressants. These are commonly divided into
three classes : Hypnotics or Soporifics, Narcotics and Anaesthetics.

HYPNOTICS OR SOPORIFICS are drugs which produce sleep,
closely resembling, if not identical with, natural sleep. The
brain during sleep is anaemic, and it is thought that this anaemia
is the cause of sleep ; possibly some soporifics act by producing
cerebral anaemia.



The hypnotics are

(1) Opium.

(2) Morphine.

(3) Chloral hydrate.

(4) Chloralamide.

(5) Butyl-chloral hydrate.

(6) Bromides.

(7) [Trional.

(8) Pellotine.]



(9) Sulphonal.

(10) Paraldehyde.

(11) Alcohol.

(12) Hyoscine.

(13) Cannabis Indica.

(14) Urethane.

(15) Lupulus.

(16) Lactucarium.



Therapeutics. These drugs are often used for persons suf-
fering from sleeplessness, but it is far more important to remove
the cause of the sleeplessness. Sleep is often promoted by dila-
ting the vessels of other parts of the body than the brain ; for
example, a warm bath or an abundant meal conduces to sleep.
The use of hypnotics is greatly abused. Those who take them
become habituated to them, so that at last even large doses do
not cause sleep. Chloral [hydrate if used with great caution,
pellotine, paraldehyde, trional], and chloralamide are perhaps
the most satisfactory.

NARCOTICS are substances which not only produce sleep, but
also in large doses depress the functions of respiration and circu-
lation. Many of them fall also under the head of general anaes-
thetics ; others are, in smaller doses, hypnotics. All must be
given in considerable doses.

The following is a list of them.



(1) General Anaesthetics.

(2) Opium.

(3) Chloral hydrate.

(4) Belladonna.

(5) Stramonium.

All must be given in considerable doses.



(6) Hyoscyamus.

(7) Alcohol.

(8) Cannabis Indica.

(9) Lupulus.



DRUGS ACTING ON NERVOUS AND MUSCULAR SYSTEMS. IO/

Therapeutics. They are of great use in calming excite-
ment of any kind ; many of them, such as, for example, opium
and belladonna, are beneficial in relieving distress and producing
sleep in heart disease.

GENERAL ANAESTHETICS. These are drugs which lead to a
total loss of consciousness, so that pain is no longer felt ; at the
same time reflex action is abolished. They illustrate admirably
the law of dissolution, and also the fact that, after excitement,
paralysis often succeeds ; and the stages consequent upon these
laws can be readily observed in any one who is taking an anaes-
thetic. Firstly, in obedience to the law of dissolution the highest
faculty, the imagination, becomes excited, the patient sees visions
and hears noises. He next begins to chatter wildly and inco-
herently, for in the excitement of any function by a drug the
exaltation is usually irregular, and confusion results. Next, the
other motor centres of the cortex are stimulated irregularly, so
that he gesticulates, throws his arms about wildly, and tosses his
body. By this time the brief stimulation of the higher intellec-
tual faculties has probably ceased, and, in obedience to the
second law, vision, hearing, and touch are dulled, and he has
lost control over his reason, so that he feels light-headed, as he
expresses it, crying and laughing easily ; now he is totally irre-
spoasible for his actions and careless as to their results. It will
be noticed that the functions are paralyzed in the order stated in
the law of dissolution. Next there follows upon the stimulation
of the motor areas, stimulation of the heart and respiration. The
pulse and respiration both increase in number, the blood-pressure
rises, the face flushes. Then comes depression of all the functions
previously excited ; first the higher parts of the cerebrum give
way, and the patient loses consciousness neither bright lights,
sounds, nor painful impressions arouse him ; he becomes quiet,
and ceases to throw his arms and legs about ; the reflexes disap-
pear, and consequently touching the conjunctiva does not pro-
duce closing of the eyelids ; the feet do not move when they are
tickled, the pupil is contracted, and the previous quickening of
the pulse and respiration are succeeded by a slowing of their rate.
It is at this period that the patient cannot feel pain, and that



IO8 PHARMACOLOGY AND THERAPEUTICS.

therefore operations are performed. The depression of the motor
centres is followed by the depression of the muscular tone, and
the muscles become quite flaccid and cease to respond to me-
chanical stimulation. This is the degree of narcosis that is re-
quired for the easy reduction of dislocations and for the easy
manual examination of the abdominal viscera. Anaesthetics
should not be pushed beyond this stage. If they are, even the
involuntary muscles lose their tone and reflex excitability, so that
the sphincters of the rectum and the bladder relax. The depres-
sion of the pulse and respiration continues, the movements of
the chest become weaker and weaker, and slower and slower,
the pulse becomes very feeble, slow, and irregular, and the heart
finally stops in diastole. Death occurs partly by the heart and
partly by the respiration. At any period of the administration
during which recovery is possible, the functions of the body will
return in just the reverse order to that in which they were lost,
thus again illustrating the law of dissolution. It is often many
hours before the mental faculties have recovered their equilibrium,
and long after the patient can move his muscles, he cannot co-
ordinate them. There are individual differences in the different
anaesthetics and in different persons.



The general anaesthetics are

(1) Chloroform.

(2) Ether.

(3) Nitrous oxide.

(4) [Pental.



(5) Ethyl bromide.]

(6) Many other substitution

products derived from
alcohols and ethers.



Therapeutics. Anaesthetics are given to cause uncon-
sciousness, so that pain may not be experienced during opera-
tions, to relax muscles in cases of dislocations, abdominal exami-
nations, phantom tumors, etc., to relieve severe pain, such as
that of parturition, biliary and renal colic, to quiet the body
during convulsions, as in tetanus and hydrophobia.

The chief dangers of anesthetics are i. Death from shock.
This usually takes place before the patient is fully under the
influence of the anaesthetic ; reflex action is not yet quite abol-
ished, and the heart is stopped reflexly from the peripheral



DRUGS ACTING ON NERVOUS AND MUSCULAR SYSTEMS.

stimulus of the operation. This is one of the greatest and most
common dangers of anaesthetics, especially of chloroform. It is,
to a large extent, avoidable if care be taken that the patient is
fully under the influence of the anaesthetic before the operation is
begun ; often, when it is trivial, the operator is in too great a
hurry to begin, and the patient suddenly dies from failure of the
heart.

2. Death from paralysis of respiration. This is usually due
to a combination of circumstances. Too much of the anaesthetic
may have been given, respiration may be difficult because the
patient suffers from some disease of the lungs, or the operation
may demand that he should lie on his side or in some other posi-
tion which hampers respiration. It is not a very great danger,
for it is heralded by lividity ; and if then the posture is changed,
the administration of the anaesthetic is stopped, and artificial
respiration is performed, the patient usually quickly recovers ;
even if he does not, artificial respiration, with the head thrown
back and the tongue pulled out, should be carried on as long as
there is any evidence that the heart is beating, or if the patient
draws a breath when artificial respiration is stopped for half a
minute. [Patients] have recovered, although it has been neces-
sary to keep up artificial respiration for hours.

3. Cardiac failure may occur if the vapor is too concentrated.
The patient almost suddenly becomes pale, and the pulse stops.
In such a case no more of the anaesthetic should be given, artifi-
cial respiration must be kept up in the manner just mentioned,
[after] the patient [has been] inverted so that the head is lowest.
The heart may be stimulated [by large rectal injections of hot
normal saline solution or of coffee, if at hand] , by the inhalation
of amyl nitrite, by the plunging of electric needles into the heart,
or [if the reflexes are not abolished,] by flicking the chest over
the heart with hot towels and placing hot compresses over it.
[The use of brandy subcutaneously is to add the effect of one
poison to that of another. The application of the faradic cur-
rent over the cardiac region is also objectionable.]

4. Vomited matter and, if the operation is about the mouth,
blood may suffocate the patient. To avoid the first contingency



IIO PHARMACOLOGY AND THERAPEUTICS.

no food should be taken for some time before the operation, and
if the patient is sick, he should be turned on his side ; to avoid
the latter special precautions must be taken, which are described
in books on operative surgery.

For the relative advantages of the different anaesthetics and
the mode of giving each, the account of the different individual
drugs must be consulted.

G. Drugs acting on the Eye.

i. DRUGS ACTING ON THE PUPIL. The first thing to deter-
mine is whether any drug which dilates or contracts the pupil acts
locally or centrally. It is dropped into one eye : if it only acts
feebly and after some time on both eyes, it follows that it has
acted centrally after absorption from the conjunctiva into the
general circulation ; but if it acts quickly, powerfully, and only
on the eye into which it was dropped, its action is local. If it
acts on an excised eye its action must be local. If, when all the
vessels going to the eye are ligatured, the drug will act when
dropped into the eye, but will not when thrown into the general
circulation, this again shows that its action is local, and that
when it acts after being thrown into the circulation when no
vessels are ligatured, it does so because it is circulating locally
through the eye. If all the arteries and veins of the eye are liga-
tured, and the drug will not act when locally applied, although it
would before and will now, when thrown into general circulation,
it shows that its action is central, and that it acts when dropped
into the eye because some of it is absorbed. If it has been
proved by these means to act centrally, the further investigation
is difficult, for the central mechanism is complex.

If it has been proved to act locally, it may act either on the
muscular fibres of the iris, on the terminations of the third nerve
in them, or on the terminations of the cervical sympathetic in
them. Stimulation of the third nerve causes the pupil to con-
tract ; section of it causes the pupil to dilate. Stimulation of the
sympathetic causes the pupil to dilate ; section of it causes the
pupil to contract. If the pupil is dilated by the local action of
a drug, and stimulation of the third nerve will not cause it to



DRUGS ACTING ON NERVOUS AND MUSCULAR SYSTEMS. I IT

contract, but yet the muscle is responsive to mechanical stimula-
tion, it shows that the endings of the third nerve are paralyzed.
If the pupil is contracted by the drug, and, although responsive
to mechanical stimulation, will not dilate when the third nerve is
cut, it shows that the ends of the third nerve are stimulated. If
a drug locally dilates the pupil, but not as powerfully as stimula-
tion of the sympathetic, it is clear that its whole effect is not due
to a stimulation of the sympathetic ; and if the muscle remains
locally irritable, the third nerve ending must be paralyzed. A
series of similar experiments may be made with regard to the
sympathetic. By these means the mode of action of many drugs
has been made out, but often they act both on the sympathetic
and the third nerve. In the following list they will be classified
under their main actions :

Mydriatics {dilate the pupil}



A. Paralyze the termination of the third nerve.



(1) Atropine.

(2) Homatropine.

(3) Daturine.

(4) Hyoscyamine.

(5) Coniine.



(6) Gelsemine.

(7) Muscarine.

(8) Hydrocyanic Acid.

(9) Aconite.
(10) Amyl nitrite.



[pro-
bably.]



B. Stimulate the terminations of the sympathetic. Cocaine.

C. Act centrally. Anaesthetics (late in their action).

Myotics {contract the pupil}.

A. Stimulate the terminations of the third nerve. Pilocarpine, and
nicotine (probably).

B. Stimulate the muscle. Physostigmine.

C. Act centrally. Anaesthetics (early in their action), Opium.

Therapeutics. Dilators of the pupils, especially atropine
and homatropine, are used to dilate the pupil for ophthalmoscopic
examination, and to prevent or break down adhesions of the iris.
Contractors of the pupil, especially physostigmine, are used to
overcome the effects of atropine, [to prevent or break down
adhesions of the iris] , and to prevent too much light entering
the eye in painful diseases of it.



112 PHARMACOLOGY AND THERAPEUTICS.

2. DRUGS ACTING ON THE CILIARY MUSCLE. The following
drugs impair or paralyze accommodation :



(1) Atropine.

(2) Daturine.

(3) Hyoscyamine.

(4) Homatropine.

(5) Cocaine.



(6) Physostigmine.

(7) Pilocarpine.

(8) Gelsemine.

(9) Coniine.



Intra-ocular tension is increased by atropine (large doses),
hyoscyamine, and daturine. It is decreased by cocaine, hyos-
cine, and physostigmine.

Gelsemine paralyzes the external ocular muscles, especially
the elevator palpebrse and the external rectus, by its action on
the terminal nerve filaments.

Cocaine, [by] stimulating the unstriped fibres in the orbital
membrane and the eyelids, causes the eye to protrude. Coniine
produces ptosis [when given in large doses] .

The capacity for seeing blue is increased by strychnine. San-
tonin causes first violet, then yellow vision.

H. Drugs acting on the Ears. We know very little
about the action of drugs on them. Quinine and salicylic acid
cause noise and buzzing.

I. Drugs acting on the Sympathetic System. Much
of this subject has already been discussed when speaking of the
action of drugs on vessels. The curious fact has been made out
that if an animal be treated with a large dose of nicotine, or if
this be applied locally to the superior cervical ganglion, stimula-
tion of the nerve below the ganglion no longer produces its char-
acteristic effects, although stimulation above the ganglion does.

DIVISION XI. DRUGS ACTING ON THE ORGANS OF GENERATION.

A. Aphrodisiacs. These are substances which increase
sexual desire. There are conceivably many ways in which this
might take place. There is a centre in the lumbar spinal cord,
irritation of which causes erection, and this is capable of being
excited by afferent impulses proceeding from many parts of the
body, but especially from the cerebrum, and the genital organs



DRUGS ACTING ON THE ORGANS OF GENERATION. 113

themselves, or the parts in their immediate neighborhood. The
lumbar centre appears to be very dependent upon the general
health, and therefore substances which improve this are indirectly
aphrodisiacs.

The following drugs are known as aphrodisiacs ; their mode of action is
not certainly known :



(1) Strychnine.

(2) Cantharides.

(3) Alcohol.

(4) Cannabis Indica.



(5) Camphor.

(6) Phosphorus.

(7) Damiana.



B. Anaphrodisiacs. We do not know for certain of any
drugs which have a depressant effect upon the lumbar centre.
Most anaphrodisiacs act by decreasing or removing some irrita-
tion which is reflexly producing an aphrodisiac effect, but some
probably act centrally.



Drugs used as anaphrodisiacs are

(1) Bromides.

(2) Potassium iodide.

(3) Opium.

(4) Belladonna.



(5) Hyoscyamus,

(6) Stramonium.

(7) Digitalis.

(8) Purgatives.



C. Ecbolics or Oxytocics are remedies which during or
immediately after parturition increase uterine action.



They are

(1) Ergot.

(2) Quinine.

(3) Hydrastis.



(4) Savine.

(5) Rue.

(6) Powerful purgatives.



Of these ergot is by far the most important. Occasionally some of these
drugs will act upon the gravid uterus to produce abortion before parturition has
begun. They have all of them been used criminally for this purpose.

D. Emmenagogues are substances used to increase the
menstrual flow. Diminution of the menstrual flow is a symptom
of so many diseases that a large number of drugs which remedy
these are indirect emmenagogues, but the substances which seem
to have a special action in increasing the menstrual flow are



114 PHARMACOLOGY AND THERAPEUTICS.



(1) All Ecbolics.

(2) [Manganese dioxide.]

(3) Asafoetida.

(4) Apiol.

(5) Myrrh.



(6) Guaiacum.

(7) Cantharides.

(8) Borax.

(9) [Tansy.]



Among the many indirect emmenagogues the commoner are purgatives,
iron, cod-liver oil and strychnine, which act by improving the general health.
Hot foot- or hip-baths, especially if mustard be added, often aid the onset of
menstruation.

E. Substances which depress Uterine Action.

These are employed to restrain the contractions of the gravid
uterus.



They are

(1) Bromides.

(2) Opium.

(3) Chloral [hydrate.

(4) Viburnum.]



(5) Cannabis Indica.

(6) Chloroform.

(7) Antimony and potassium

tartrate.



F.. Drugs acting on the Secretion of Milk.
Galactagogues [are] drugs which increase the secretion of
milk.

[Pilocarpus, Leaves of Ricinus Communis,] and Alcohol. Of these
[pilocarpusj is the most powerful, but its effects soon pass off. [The leaves of
the castor-oil plant are used, applied as a poultice, and a decoction, or the fluid
extract of them, given internally at the same time.] Alcohol is very feeble.
The secretion is so much under the control of the general health that the best
way to insure an abundant secretion is to keep the general health as good as
possible.

Antigalactagogues [are] drugs which decrease the secre-
tion of milk.

Belladonna, either given internally or applied locally, is very efficient,
probably acting on the mammary gland as on the sweat glands.

The following drugs, if given, are excreted by the milk, and are therefore
taken in by the child : Oil of anise, oil of dill, garlic, oil of turpentine, oil of
copaiba, and probably all volatile oils, sulphur, rhubarb, senna, jalap, scam-
mony, castor oil, opium, iodine, indigo, antimony, arsenic, bismuth, iron, lead,
mercury, zinc and potassium iodide. It is clear that these must be administered



DRUGS ACTING ON METABOLISM.

with care to the mother ; for example, copaiba or turpentine will make the
milk so [unpleasant] that the child will not take it. The above purgatives,
given to the mother, may cause diarrhrea in the child. Opium should not be
given in large doses to the mother. On the other hand, mercury, arsenic, and
potassium iodide may be administered to the child by being given to her.

DIVISION XII. DRUGS ACTING ON METABOLISM.

Our knowledge of the normal metabolism of the body is very
imperfect, consequently we know very little more than has already
been stated under other divisions, about the action of drugs on
metabolism. Any further remarks which are necessary will be
made when the individual drugs are considered. Two words in
common use are alterative and tonic.

Alterative is a vague term of which no definition can be given. It is
often used to cloak our ignorance, when we have no exact knowledge of the



Online LibraryWilliam Hale-WhiteMateria medica, pharmacy, pharmacology and therapeutics → online text (page 9 of 67)