This section is from the book "A Treatise On Therapeutics, And Pharmacology Or Materia Medica Vol1", by George B. Wood. Also available from Amazon: Part 1 and Part 2.
It is uncertain whether belladonna was used by the ancients as a medicine. The earliest account we have of its employment in modern times was about the close of the seventeenth century, when it appears to have passed from empirical use into the hands of the regular profession. At first it was chiefly valued as a remedy in cancerous tumours and ulcers, of which it was supposed sometimes to effect cure3; and cases were recorded which would go far to confirm this opinion of its powers, did we not know how frequently erroneous diagnosis has led to false estimates of the efficacy of medicines in these affections. At present there are very few who would maintain that belladonna could do more than palliate in true cancer. But, though now little employed in those complaints for the cure of which it was first brought into notice, it has been found, by abundant experience, to possess powers which render it highly useful for various other purposes.
Indications. The chief indications which belladonna is calculated to fulfil are, 1. to subdue pain, 2. to relax muscular spasm and rigidity, 3. to stimulate the nervous centres, and 4. in reference specially to the eye, to lessen the sensibility of the retina, and dilate the pupil. As a soporific, it cannot be relied on, and is, I believe, never employed.
One mode in which it operates, in answering these purposes, is by rendering the nervous centres insusceptible of irritative impressions, and incapable of transmitting irritative action; but there can be no doubt that it is capable also of operating directly on the peripheral sensibility of the nerves, and of producing the same insusceptibility at their extremities as at their centres. Whether it acts in this way by an immediate or by an indirect sedative agency it would not be easy to determine; but, as the evidence is irresistible that it occasionally does stimulate the nervous centres, it is safest to admit that in this respect its action is uniform, and that the depression evinced is an indirect result of an active congestion in all instances. What tends to confirm this view is, that the medicine has not been found applicable to cases, in which the nervous centres were already in a state of active congestion or inflammation; the very condition in which it would seem to be specially indicated, were it directly sedative.
In the relief of painful and spasmodic affections, belladonna seems to be capable of something more than a mere temporary influence. Not only does it give ease; but, by a perseverance in its use, we not unfre-quently obtain positive cures from it, which opium itself, though more powerful as a mere anodyne, is unable to effect. It would appear, therefore, to produce some permanent modification in the nervous tissue, incompatible with that which existed in its morbid condition, in other words, to act as an alterative as well as an anodyne. Another advantage which it possesses over opium, in the treatment of chronic or frequently repeated painful affections, is its entire exemption from the liability of abuse as an exhilarating agent, which constitutes one of the greatest objections to the use of that most fascinating drug.
The contraindications to the use of belladonna are, as in this class of medicines generally, active congestion or inflammation of the brain, inflammation of the stomach, high inflammatory or febrile excitement, and a plethoric state of system; in all which conditions, should any special symptom call for this remedy, its use should be preceded by depleting measures.
I shall treat of the special complaints in which belladonna is used, under the several indications above mentioned.