Heard and Brooks (1913) tested camphor on human beings. In 5 cases with normal circulation a hypodermatic of camphor, 20 grains (1.3 gm.) in oil, showed in four no change in the circulation, and in the other one a fall of 17 mm. in systolic and 25 mm. in diastolic pressure. In 9 cases with auricular fibrillation and other cardiovascular conditions there was no change, except in 2 of them a very slight rise in pressure. Their observations were made for from forty to two hundred and seventy minutes after the injection. The only rises in pressure were in cases with great mental excitement, and in these, on a second test, there was no rise. Even as much as 50 grains (3.3 gm.) failed to produce any definite effects, either desirable or toxic. In perfusing a cat's isolated heart, camphor in saturated solution was without effect on the normal heart, but in 2 instances checked experimental fibrillation. Leo (1913) obtained a rise of 20 to 30 mm. mercury from 200 c.c. of a saturated solution in Ringer's fluid.

We do not think it should be used as a heart stimulant at all, except as a single dose in emergency. Even then it is entirely unreliable. (See Fig. 57, page 458.)

Respiratory Organs

As with other carminatives, there is a reflex stimulation from the stomach or mouth. Systemically, after large doses, there is some stimulation of the respiratory center. Edsall and Means found this stimulation very slight. It is thought that some of the drug is eliminated in the bronchial mucus; but if this is so, the dose of a few grains is too small for any effective remote local action.


Given by mouth, camphor tends to lessen hysteric excitement and nervous instability. All strong carminatives do this to some extent, but camphor, valerian, and a few other drugs seem to exert an antihysteric influence quite out of proportion to their value as carminatives. This probably is the effect of stimulation of the higher controlling centers of the brain (those governing reason, self-control, will, etc.). That camphor is a cerebral stimulant is shown by increased intellectuality, and by the appearance, after excessive doses, of delirium, maniacal excitement, motor restlessness, and even epileptiform convulsions.


The slight stimulation of the respiratory and vagus centers and the intermittent stimulation of the vasoconstrictor center have been mentioned above.

Peripheral Nerves

Prolonged application to the skin of a strong preparation, such as menthol-camphor, results in a lessening of the pain sense from depression of the ends of the sensory nerves.


The dilatation of the skin vessels promotes sweating and allows more blood to come to the surface of the body to be cooled, so the drug tends to lower temperature in fever and to lessen internal congestion (hence its use internally in colds). But camphor is not a strong antipyretic.


It is said to be aphrodisiac, but there is just as much evidence that it is anaphrodisiac. As a matter of fact, the powerful psychic factors brought to play in sexual manifestations render it very difficult to judge of the effect of a drug in this field.


All tend to be slightly increased, the sweat and mucus particularly. This is of too little degree, however, to be of use in medicine.


In the urine, combined with glycuronic acid, also in the sweat and feces, and perhaps in the bronchial mucus.


There have been a number of deaths from camphor. The symptoms are those of cerebral stimulation, viz., intellectual and motor activity, great excitement, even to maniacal delirium, and epileptiform convulsions. This stage is followed by collapse, coma, and death. The treatment is whisky and bromides.

Some years ago, while a medical student, I came across a case of death in a child of two years from one teaspoonful of spirit of camphor, i. e., 6 grains (0.4 gm). Recently one of my female patients took a tablespoonful of the spirit of camphor, i. e., 24 grains (1.6 gm.) of camphor, and became wide awake and excited and had real intellectual stimulation, as if she had taken strong coffee. Motor activity was not pronounced, but for several hours there was a sense of loss of power in the legs. The alcohol present, which was as much as in one ounce of whisky, possibly served as an antidote and prevented more marked effects. It may indeed have been the cause of the sensation of diminished power in the legs. Austregesillo reports convulsions in 5 cases from doses of 10 to 22 grains (0.6-1.5 gm.). Barker reports the death of a female child, sixteen months old, after swallowing probably 1/2 ounce of camphorated oil (48 grains of camphor), some of which was vomited. Heard and Brooks report the injection of 50 grains (3.3 gm.) in oil without toxic manifestations.


Locally, it may be employed - (1) As a counter irritant. Camphorated oil is a very weak preparation, but may be used for children. It is rubbed into the skin in pain or inflammation of the chest and throat, and in neuralgic and muscular pains. For adults the camphorated oil may be mixed with an equal quantity of the oil of turpentine. Menthol-camphor and choral-camphor are strong liquids which are employed in toothache, neuralgia, and muscular and joint pains. (2) As a cooling application - the spirit is applied in headache and in itching and erythema of the skin. It acts as an evaporating liniment. (3) As a stimulant and antiseptic to mucous membranes in catarrh of nose and throat. It may be added to oily sprays, or used by inhalation. (4) As a carminative in flatulence or colic (spirit or water). (5) As anti-diarrheic (spirit, or pills of camphor and opium).

Systemically, it may be employed - (1) In colds, to lessen internal congestion and fever. (2) As an antipyretic in fever mixtures (as camphor water). (3) To overcome nervous instability and hysteric conditions. (4) Possibly as an emergency circulatory stimulant in collapse or shock. (5) In pneumonia, Seibert (1913) recommends hypodermatic doses of 1 c.c. of a 30 per cent. camphorated sesame oil for each 10 pounds of body weight. He precedes the dose with 2 per cent. cocaine and repeats it every eight or twelve hours.


For carminative or systemic effects, the water or the spirit, the latter being dropped on a lump of sugar.

For diarrhea the preferred preparations are Squibb's Diarrhea Mixture, Sun Cholera Drops, and Camphor and Opium Pills - camphor, 2 grains (0.13 gm); opium, 1 grain (0.06 gm.).

As a circulatory stimulant it is employed hypodermatically in solution in alcohol, ether, or oil (camphorated oil is a 20 per cent. solution in cottonseed oil). These solutions are irritant to the tissues.