Source and Composition. The leaves and root of Atropa Belladonna, a European plant of the order Solanaceae. It contains two alkaloids, Atropine, the active principle, and Belladonnine, also a coloring matter named Atrosin, and Malic Acid.
Derivatives of Atropine. It is resolvable into Tropin and Tropic Acid, and may be made synthetically.
- Tropeius is the result of treating Tropin with a mineral acid.
- Homatropine is obtained by the action of dilute HCl Acid upon the Amygdalate of Tropin, and is used by ophthalmologists as Hydrobromate of Homatropine. It slows the heart—Atropine quickens it.
- Extr. Belladonnae Foliorum Alcoholicum, Alcoholic Extract of Belladonna Leaves,—Dose, gr. 1/10-1/2.
- Tinctura Belladonnae Foliorum, Tincture of Belladonna Leaves,—strength, 15 per cent. Dose, ♏j-xxx.
- Extr. Belladonnae Radicis Fluidum, Fluid Extract of Belladonna Root,—Alcohol, 80 per cent. Dose, ♏j-v.
- Emplastrum Belladonnae, Belladonna Plaster,—has of the alcoholic extract of the leaves 20 per cent.
- Unguentum Belladonnae,—has 10 per cent, of the extract.
- Linimentum Belladonnae,—has Camphor 5 per cent, in the Fluid Extract of the root to 100.
- Atropinae Sulphas, Atropine Sulphate,—Dose, gr. 1/200-1/60. Hypodermically give ♏ij-iv of a solution containing gr. j to the ℥, each minim of which equals gr. 1/480.
Physiological Action. Belladonna is an irritant narcotic, a mydriatic, an anti-spasmodic, an anodyne; in small doses a cardiac, respiratory and spinal stimulant, in large doses a paralyzer of the secretory and motor nerve endings, and a stimulator of the entire sympathetic system. It produces dryness of the mucous membranes of the throat, mouth, nose and larynx; and at first lessens the gastric and intestinal secretions, but soon reproduces them in large quantity.
The Heart-rate is at first slowed, but soon becomes very rapid and vigorous, the pulse being doubled in rapidity; the arterial tension being at the same time raised, the circulation is greatly increased. This the drug accomplishes by stimulating the cardiac sympathetic, and paralyzing the intra-cardiac inhibitory ganglia, thus stimulating the accelerator apparatus while lessening inhibition. [Digitalis increases both.] The vaso-motor ganglia all over the body are stimulated, but afterwards paralyzed by over-stimulation, the heart weakens, the vessels relax, and the blood-pressure is greatly lowered. Complete motor paralysis follows, then delirium, stupor, and finally death, usually by asphyxia.
The Pupils are dilated by the local or systemic use of the drug, by stimulation of the end organs of the sympathetic, and paralysis of those of the motor oculi, thus increasing the power of the radiating iris fibres, and lessening the action of the circular fibres. Atropine also paralyzes accommodation, and lessens the intra-ocular pressure. The least quantity of Atropine affecting the pupil is stated at (Wood), 1/20000 (Roosa), gr. 1/40000 (Ely), gr. 1/128600 (Trousseau), gr. (Lacing,) gr. 1/700000 (Donders).
The Brain is congested by Belladonna, a busy delirium being produced, and hallucinations with mental disorder, due to a selective action on the cells of the gray matter.
The Spinal Cord is stimulated from the 2d cervical vertebra to the 10th dorsal, resulting in paralysis of the motor nerves, central and peripheral; power being lost in the lower extremities first. Sensation is slightly impaired, but the muscular irritability is not. Respiration is increased, and the temperature raised. By the increased circulation metamorphosis is greatly promoted.
A Diffused Eruption of a scarlet color, greatly resembling that of scarlet fever, is often produced by Belladonna on the skin and fauces, with dysphagia and sore throat, and is sometimes followed by desquamation. It is due to capillary congestion caused by the greatly increased circulation.
Diffused rapidly, Belladonna is also quickly eliminated, particularly by the kidneys. The urine of an animal under the action of Atropine will dilate the pupil of another animal. Herbivorous animals and birds are scarcely susceptible to the action of Belladonna, and pigeons are not affected by it at all.
Antidotes and Antagonists. In poisoning Tannic Acid and emetics should be used. Opium is the physiological antagonist for its effects on the cerebrum, pupil, heart, respiration, arterial tension, and kidneys. Physostigmine, Aconite, Pilocarpine and Quinine are each antagonistic to some of its effects; Muscarine to most of them.
Therapeutics. Belladonna is especially useful in—
- Pain of inflammation—particularly that of gout, rheumatism, neuralgia due to peripheral disturbance, sciatica, cancer, and pelvic affections.
- Cerebral and Spinal Hyperaemia, congestive headaches, encephalitis, meningitis and myelitis,—it proves one of the very best remedies.
- Erysipelas of superficial and non-vesicular character, and when cerebral,— Belladonna is curative in 5 ♏ doses hourly, also the extract locally.
- Inflammation of the lungs, iris, bladder, kidneys and breasts, are all amenable to Belladonna applied locally, or Atropine used hypodermically.
- Constipation due to atony of the bowels,—it is remarkably efficient; the Tincture combined with Nux Vomica and Physostigma Tinctures, equal parts of each, of which combination give 15-drop doses at night.
- Enuresis of children,—large doses (gtt. x-xx of Tincture) thrice daily.
- Cystitis, recent, from chill,—the Tincture internally, and the Extract applied to the perineum, are very efficient treatment.
- Spasm of the urethra, bladder, anal sphincter, etc.,—is overcome by it.
- Ulcers of the rectum, anal fissures, etc.,—are soothed and healed by the use of the Extract locally, or the ointment.
- Ptyalism from Mercury, pregnancy, etc.,—is arrested by Atropine.
- Abscesses, boils, carbuncles, and other superficial inflammations, are remarkably benefited by Belladonna with Morphine, used locally.
- Typhus and Typhoid in their early stages,—Belladonna is very useful.
- Acute Nasal Catarrh, with profuse watery discharge,—it is very efficient.
- Sore Throat, with fever, inflammation, redness, and swollen tonsils.
- Scarlet Fever,—Belladonna is said to be prophylactic (?). It relieves many of the symptoms of this disease, and is well used when the rash is imperfect, the pulse feeble, and the condition adynamic.
- Skin Diseases,—notably erythema, eczema, herpes zoster and prurigo.
- Sweats of Phthisis,— gr. 1/60 of Atropine is generally effective.
- Asthma and Pertussis,—are well treated by Belladonna in full doses.
- Cardiac Failure when sudden,—Atropine as a cardiac stimulant.
- Convulsions, epileptic and puerperal,—are often relieved by Belladonna.
- Spermatorrhoea and seminal losses,—are best treated by this remedy.
- Poisoning by Opium, Physostigma and Prussic Acid. In Opium poisoning the unsuccessful cases treated by Atropine are due to overdosing therewith (?). It should be given in very small doses, and for effect.
- Ophthalmologists use Atropine to paralyze accommodation, dilate the pupil, contract the vessels, lessen pain, and diminish intra-ocular tension.
A Compend of Materia Medica, Therapeutics, and Prescription Writing, 1902, by Sam'l O. L. Potter, M.D., M.R.C.P.L.