An alkaloid obtained from belladonna. As it occurs in commerce, it is
always accompanied by small proportion of hyoscyamine extracted along
with it, from which it cannot readily be separated.
DERIVATION.--Atropine is obtained from a strong tincture of the root.
PROPERTIES.--A white crystalline powder, very soluble in water and
alcohol.
DOSE.--Horses, ¹⁄₂ to 1¹⁄₂ grs.; cattle, 1 to 2 grs.; sheep and pigs,
¹⁄₂₀ to ¹⁄₁₂ gr.; dogs, ¹⁄₁₅₀ to ¹⁄₅₀ gr. The doses should be
considerably reduced when used with morphine.
INCOMPATIBLES.--Caustic alkalies; antagonize physiologically by
pilocarpine and physostigma throughout almost whole range of its
influence, and opium within a certain limitation, prevents the
respiratory failure, which is the cause of death.
ACTION.--Belladonna is an irritant narcotic, a mydriatic, an
antispasmodic and anodyne. In small doses a cardiac, respiratory and
spinal stimulant; in large doses a paralyzer of the sensory and motor
nerve endings and a stimulator of the entire sympathetic system.
It produces dryness of the mucous membrane of the throat, mouth, nose
and pharynx, and at first lessens the gastric and intestinal secretions,
but soon produces them in large quantities. It is anti-galactogogue,
that is, it arrests secretion of milk.
The heart rate is at first slowed, but soon becomes very rapid and
vigorous, the pulse being doubled in rapidity; arterial tension is
raised and the circulation greatly increased.
The pupils are dilated by the local or systemic use of the drug.
The brain is congested by belladonna, a busy delirium being produced,
and hallucinations with mental disorder, due to a selective action on
the cell of the gray matter.
The spinal cord is stimulated from the second cervical vertebrae to the
tenth dorsal, resulting in paralysis of the motor nerves, both central
and peripheral, power being lost in hind extremities first. The
respiration is increased and the temperature is raised by the increased
circulation; metamorphosis is greatly promoted.
Belladonna and atrophine are rapidly diffused and quickly eliminated by
the kidneys. By its paralyzing effect on the terminal nerve filaments,
it relaxes the bronchial tubes and checks the secretion of the bronchial
mucous membrane; it checks secretion of saliva and milk in the same way
and causes dryness of the skin.
USES.--Belladonna and atrophine is indicated anywhere that an
antispasmodic and anodyne is needed. Is serviceable in catarrh,
pharyngitis and bronchitis to check secretion in second stage; heaves,
especially asthmatic heaves, combined with gelsemium and lobelia,
followed by Fowler’s Solution; in influenza, it stimulates the weakened
heart, besides having other good effects.
In the first stage of respiratory diseases, belladonna alone, or
combined with aconite or other febrifuges and expectorants; in cough,
especially spasmodic or when due to irritation of the throat; in heart
failure or heart weakness, hypodermic injections of atrophine are
beneficial; in spasmodic colic one to two drachms of the fluid extract
to a dose, but one drachm is usually sufficient; as a powerful
antispasmodic and anodyne, atropine and morphine combined; small doses
are given in constipation of the bowels, combined with nux vomica; small
doses with purgatives are said to aid their action.
In tetanus give one to two drachms of the extract two or three times
daily; in paralysis of the throat of tetanus the fluid extract combined
with soap liniment or used alone externally; in cerebro-spinal
meningitis, belladonna and ergot alternated with aconite is rational
treatment, conjoined with the external treatment. It allays irritations
of the bladder, rectum, and uterus, especially if combined with cannabis
indica.
In contraction or rigid os the extract applied directly, quickly relaxes
and allows parturition; it is well to see if this is necessary before
giving ergot.
Used extensively in examinations and diseases of the eye.
Atrophine sulphate is used locally to dilate the pupil, assisting in the
detection of cataracts or other disorders of the eye and testing the
condition of the refracting media; for dilating pupil use a solution of
four grains of the atrophine to one ounce of distilled water; a few
drops are placed into the eye, for inflammation of the eye with great
irritation; belladonna may be combined with cocaine; in iritis.
ANTIDOTE.--In poisoning, tannic acid should be used.