Physostigma. Physostigma venenosum

Botanical name: 

Synonyms—Calabar bean, Ordeal bean, Chop nut.

Physostigmine or Eserine, Calabarine, Eseridine, Phytosterin.


Extractum Physostigmatis, Extract of Physostigma. Dose, from one-twentieth to one-eighth of a grain.
Tinctura Physostigmatis, Tincture of Physostigma. Dose, from three to ten minims.
Specific Medicine Physostigma. Dose, from one-fourth of a drop to five drops. Prescribed, from eight drops to two and one-half drams, in four ounces of water. A teaspoonful every two to four hours,
Physostigmine or Eserine—A crystalline solid, white or pinkish colored, readily soluble in alcohol, sparingly soluble in water. Dose, 1/150 to 1/30 of a grain.
Physostigmine Sulphate—A crystalline powder, whitish or yellowish white, changing on exposure to a pink or reddish color, bitter, odorless, deliquescent; freely soluble in alcohol and water. Kept for preservation in amber-colored vials. Dose, 1/150 to 1/30 of a grain.
Solutions of one grain of physostigmine or its sulphate to the ounce of distilled water is used in the eye, one drop three or four times daily.

Physiological Action—The first effect of calabar bean upon internal administration in overdoses is local—a sense of burning and irritation in the stomach, with nausea, vomiting and purging. The salivary, gastric and in testinal secretions are all greatly increased. It stimulates unstriped muscular fiber, producing in the intestinal canal increased peristalsis. There is inactivity, prostration, cold, pallid skin and muscular incapacity.

The evidences of the action of this agent upon the nervous system are not marked. No pain is produced and the consciousness of the patient is usually retained. Probably, from deficient oxygenation of the blood, there is vertigo, which may finally induce narcosis. There are ultimate paralysis and temporary tetanic convulsions. There is abolition of motor reflex.

The arterial tension is at first lowered, then increased, the heart is slowed. There is a reduction in the number and force of the pulsations. The influence seems to be entirely upon the muscles of the heart, through overstimulation of the cardiac ganglia, and not through the central nervous system. The heart finally loses its contractility, is flabby, and fails in diastole. The respiration becomes slower, is shallow and feeble, and finally ceases. The heart continues to pulsate with increasing feebleness for some little time after respiration has ceased. The blood is loaded with carbonic acid gas, and the corpuscles are altered in their character.

The general muscular relaxation from this agent is most marked. Small, long continued doses induce feebleness and indisposition to muscular exertion. By full doses, tremors of the voluntary muscles are induced, and finally complete muscular paralysis. The muscular structure of the walls of the intestines is sometimes affected by tetanic spasm, followed by complete relaxation and paralysis.

The mind may continue clear. The influence, at first stimulant, is finally motor depressant, abolition of reflexes appears, with ultimate paralysis of the motor nerves, more slowly occurring.

It is quickly absorbed and readily eliminated through all the emunctories.

Upon the eye, when locally applied, this agent acts first by contracting the pupil. It afterward decreases intraocular tension, and produces spasm of accommodation and myopia. There is often pain of a severe contractile character produced in the eyeball.

Specific Symptomatology—The remedy is indicated when there is a feeble pulse, tremulous, perhaps slightly irregular, cool extremities and cool surface, breathing more or less difficult, with a sense of constriction. These symptoms are found present in some cases of cerebro-spinal meningitis. Administered in minute doses in this disease, it will be found to occupy a place between belladonna and gelsemium. It may be given in conjunction with echinacea with very good results. It overcomes the tendency to mental dullness and stupor and wards off impending coma. The agent is useful where there is torpor, inactivity, atonicity of the intestinal canal, and of the organs of digestion and appropriation, or where from lack of nerve force there is deficient secretion, dryness of the mucous membranes, deficient glandular secretions with dry and hardened feces.

It increases the contractility of the muscles of the bladder walls, and of the uterus.

Although a motor depressant in large doses, in small medicinal doses it has a contrary influence.

Therapy—The agent may be given internally to allay the tension induced by extreme nervous irritation. Convulsive disorders from irritation are allayed by it, but it is not in general use for this purpose.

It has been used in tetanus, in epilepsy and in convulsions from all causes, also in locomotor ataxia, in chorea and in progressive paralysis of the insane. Its influence has not been such as to justify dependence upon it in these cases.

It stimulates the respiratory function and heart's action where there is great depression with difficult breathing, with a sense of compression or constriction of the chest, with soft, feeble pulse, cool, moist skin, and usually dilated pupils. It is the remedy for dyspnea under such circumstances. It is also advantageous where the dyspnea is caused by a clogging up of the bronchi and air cells without power to expel the thick tenacious mucus. It will liquefy the secretion and increase the power to expel it.

In emphysema and in asthma with great muscular relaxation, in bronchitis with dilatation, it is useful. It restores tone in phthisis and overcomes night sweats of that disorder.

It may be of advantage in dilatation of the stomach, and in atony and extreme inactivity of the intestinal muscular structure. In intestinal catarrh from this cause it is of much service. It is also valuable in catarrh of the mucous linings of the kidneys and bladder, and in extreme atony, relaxation and plethora of the abdominal structures. It will assist in overcoming chronic constipation and a tendency to flatulence in atonic cases.

It is useful in tympanites and flatulence present during the menopause, where there is atonicity of the intestinal walls and constipation. In the condition known as phantom tumor it has been used advantageously.

Its chief influence is upon the eye. When mydriasis has been induced by atropine or other agent, a solution of the sulphate of eserine will quickly restore the normal condition. Any adhesions of the iris which may have occurred as the result of inflammation may be broken up by this agent. It is used to reduce intraocular tension, as has been stated, and to increase the power of the muscles of accommodation, being valuable in paralysis of these muscles.

It is useful in conjunctival inflammations where perforating ulcer threatens to permit prolapse of the iris. It is especially advised when ulceration without determination of blood—indolent in character, nonvascularized—is present. It is useful in intermittent strabismus, in glaucoma, asthenopia, in photophobia and in some cases of neuralgia of the eyeball. After injury to the eyeball many conditions may occur which will be promptly relieved by the use of this agent.

Edison of Indiana wrote some years ago an excellent article on the treatment of meningitis, in which he lays great stress upon the action of this remedy. Whether the difficulty be spinal or cerebro-spinal, whether it be acute or chronic in character, he claims to obtain benefit in all cases, and cure in the larger percentage of cases, by the direct influence of calabar bean, especially if there be an underlying primary congestion, plainly apparent. He uses in conjunction, however, counter irritation in all cases.

To an infant he gives of a mixture of from eight to ten drops of the tincture in four ounces, a teaspoonful every half hour. To an adult he would administer two drops every fifteen minutes, until spasms or marked symptoms are under control, then he would give the dose every two or three hours. He lays great stress upon small doses frequently and persistently repeated. I believe it more useful if given in careful combination with gelsemium.

The remedy is useful in the treatment of spinal irritation, in one or two drop doses, frequently administered. The doctor has depended upon this remedy for twenty-five years, and the results have established a fixed confidence in its influence.

Co-operatives—It may be combined with xanthoxylum, strychnine, nux vomica or capsicum with advantage. Belladonna will facilitate its action, also, in its influence upon gastrointestinal structures.

The American Materia Medica, Therapeutics and Pharmacognosy, 1919, was written by Finley Ellingwood, M.D.
It was scanned by Michael Moore for the Southwest School of Botanical Medicine.