Ammonii Bromidum.—Ammonium bromide. Bromure d'ammonium, Fr.; Bromammonium, Ger. Colorless, transparent, prismatic crystals, or a white, granular salt, becoming yellow on long exposure to air, odorless, having a pungent, saline taste, and a neutral reaction. Soluble in 1·5 part of water and in 150 parts of alcohol at 60° Fahr.; in 0·7 part of boiling water. Dose, gr. x— 3 ss, or more, well diluted.

Calcii Bromidum

Calcium bromide. A white, granular salt, very deliquescent, odorless, having a pungent, saline, and bitter taste, and a neutral reaction. Soluble in 0·7 part of water and in 1 part of alcohol. Dose, Эj—3 ij.

Camphora Monobromata

(For description, see article Camphora.) Ethyl Bromide.—(For description, see article AEther.) Lithii Bromidum.—Lithium bromide. A white, granular salt, very deliquescent, odorless, having a very sharp, somewhat bitter taste, and a neutral reaction. Very soluble in water and in alcohol. Dose, gr. v—Эij.

Potassii Bromidum

Potassium bromide. Bromure de potassium, Fr.; Bromkalium, Ger. Colorless, translucent, cubical crystals, permanent in dry air, odorless, having a pungent, saline taste, and a neutral reaction. Soluble in 1·6 part of water and in 200 parts of alcohol at 60° Fahr. Dose, Э j— 3 ij.

Sodii Bromidum

Sodium bromide. Small, colorless, or white monoclinic crystals, or a crystalline powder, permanent in dry air, odorless, saline taste and neutral reaction. Soluble in 12 parts of water and 1·3 parts of alcohol. Dose, Эj—3 ij.

Antagonists and Incompatibles

Acids, acidulous and metallic salts are incompatible with bromides of ammonium and potassium, and nitrous ether with the former. The physiological actions of the bromides are antagonized by cold, digitalis, belladonna, ergot, and other agents which energize the vaso-motor nervous system.


Opium, chloral, and remedies belonging to the same group, promote the action of the bromides on the brain; and aconite, veratrum viride, gelsemium, etc., increase the depressing effect of the bromides on the circulatory system.

Physiological Actions

The taste of a bromide is bitter and saline. In a short time after it is swallowed, the characteristic taste returns to the mouth, owing to the outward diffusion of a portion of that administered. The tactile sense of the fauces, as also the muscular movements in the act of swallowing, are diminished by long-continued use of the bromides.

Sixty grains of the bromide of potassium or sodium, and a less quantity of the ammonium salt, will in some persons produce slight nausea and diarrhoea; in others, a sense of coolness in the epigastric region; but in many, provided the salt is properly diluted, no effect on the stomach. Gastric catarrh is undoubtedly one of the evil results which may follow the protracted administration of the bromides in considerable doses.

These are diffusible substances, and hence pass quickly into the blood. When large doses are administered and insufficiently diluted, it is probable that no inconsiderable portion escapes absorption, for they can be detected in the intestinal mucus and in the faeces.

Very obvious effects on the action of the heart, on the respiration, and on the animal temperature, are produced by the bromides if administered in considerable quantity. These functions are depressed, but the depression is much less evident as to temperature; hence, in order to determine this result, most careful observations are necessary. The author has ascertained that two drachms of bromide of potassium will lower the temperature in a healthy adult from one fifth to one half a degree; the respirations from two to five, and the pulse from ten to twenty beats per minute. These effects are more pronounced in animals, as ascertained by the administration of lethal doses. In man the number of the cardiac pulsations is not only reduced, but their force is diminished, and the tension of the arterial system is lowered.

A transient excitement, intoxication, giddiness, in some persons an anxious mental state, are produced by one or several large doses. As a rule, slight somnolence, and sounder and more refreshing sleep result, provided no disturbing element intervenes. The pupil is not affected in its size and sensibility to luminous impressions in an adult man by a dose of one hundred and twenty grains. When long continued, the hypnotic effect is much more pronounced, and a constant drowsiness is experienced. The sensibility to pain, but especially the sensibility to tactile impressions, is lowered by the bromides at all accessible points of the mucous membrane, and of the skin—notably of the plantar surfaces of the hand and foot. The diminution of the sensibility of the mucous membranes is in part due to a local action of the salt as it is being eliminated.

Motility is impaired by the long-continued use of the bromides in man, and in animals paralysis of the muscles ensues. If injected into the tissues of a limb, paralysis of motion and sensibility begins in that member. In man the impaired motility is probably due to other factors as well as to the action of the bromides on the muscular tissue, viz., to the cutaneous anaesthesia, and to an anaemia of the co-ordinating centers, in consequence of which their functional power is lowered.

A very notable effect of the bromides—chiefly bromide of potassium—is the diminution of the sexual feeling and of the power of erections produced by it. This fact has been established by abundant clinical evidence. The result is not, however, produced with equal facility in all cases, and considerable doses are necessary in any case.

Prolonged administration of the bromides develops a peculiar state, to which the term bromism is applied. This condition of chronic poisoning differs from the effects of a few medicinal doses in the extent and intensity, but not in the character, of the symptoms. The following were the symptoms of bromism, as observed in an epileptic boy, to whom two drachms of the bromide of potassium had been administered daily for a month: extreme pallor and anaemia, dilated pupils, acne on face, forehead, and shoulders; a fetid, bromine breath; slow and feeble action of the heart; breathlessness, and quickened pulse on slight exertion; cool hands and feet; a general subjective sense of coldness; movements in walking tremulous and uncertain; diminution of the tactile sensibility of both cutaneous and mucous surfaces; fauces dry, and the reflex movements sluggish; swallowing somewhat difficult; antaphrodisia and complete relaxation of the genitals; mind weak, manifested in silly conduct and unmeaning laughter

Various mental symptoms are in some subjects produced by the long-continued use of the bromides. Weakness of mind, without perversion of intellection, is a very constant result of the continued use of large doses. Headache, confusion of mind, and a peculiar intoxication, had long ago been observed to follow the use of the bromide of potassium in even moderate doses (Puche). A form of mental derangement, with hallucinations of a melancholic character, has been observed by Hammond and others, and in a few instances a pleasurable intoxication, with exalted ideas, has been produced (Bannister).

The pallor and anaemia of bromism are due to several causes: to the diminished action of the heart; slowness of the capillary circulation, and consequent interference in the metamorphosis of tissue; derangement of digestion and assimilation in consequence of gastric catarrh; and diminished blood-supply to the cerebro-spinal axis. The disorders of voluntary movement, the uncertain gait, the apparent defects of co-ordination, are variously explained; but, they are doubtless made up of several factors, of which the cutaneous anaesthesia is the most influential. The bromides possess the power to destroy or impair the irritability of the motor and sensory nerves, and the contractility of muscle, and to these effects must be attributed in part the disorders of voluntary movement noted above.

It is very obvious that the bromides depress certain organic functions: they diminish the action of the heart, lower the animal temperature, and lessen the blood-supply to various organs. These results can only be accomplished by a sedative influence on the sympathetic system. Some very accurate observers have maintained that in this action lies all of the physiological power of the bromides (Reynolds, Amory).

Effects of the Bromides compared

There is a general correspondence in the actions of the different bromides. As respects their influence on the pulse, body-heat, and respiration, the author's comparative experiments have demonstrated that these agents stand to each other in the following order: bromide of sodium, bromide of lithium, bromide of potassium, bromide of ammonium. Very notable differences exist between the bromide of ammonium and the others, due, undoubtedly, to the character of the base.

The author's experiments on animals further demonstrated the following: bromide of potassium possesses the most toxic power, and bromide of sodium the least. The bromide of lithium is first, the bromide of sodium second, and the bromide of potassium third, in hypnotic power. As respects the influence of these agents severally on the reflex faculty of the spinal cord, it may be stated that none of them possess the power to abolish the reflex faculty except when administered in sufficient quantity to produce lethal effects. Considered from this point of view, the bromides may be grouped as fol lows: bromide of ammonium, bromide of potassium, bromide of lithium, bromide of sodium.

The elimination of the bromides takes place through the mucous membrane of fauces, intestinal canal, and bronchi, through the skin, but chiefly by the kidneys. The rate of elimination varies, but is usually slow, several days being occupied in its diffusion outwardly from the blood.