Rhus Toxicodendron.

Botanical name: 

Syn.—Rhus Tox; Poison Oak; Poison Ivy.
P. E.—Fresh leaves.
N. O.—Anacardiaceae.
N. H.—North America.

Properties: Stimulates cutaneous and renal secretions.

Physiological action: Rhus tox. emits its poison in the air around where it grows so that people who are susceptible to its action will become poisoned without coming in contact with it. When the plant is broken or moist it will charge the air around it even more. Handling it is dangerous to some while others can do so with impunity. Worst of all is to inhale the fumes of burning roots, shrubs or leaves. When the poisonous action results, it first causes severe itching and burning which is followed by redness and swelling of the affected parts. This inflammation of the skin may be in patches or spread to various parts of the body, effect usually lasting about two weeks. In severe cases it may spread all over the body, the affected parts swelling sometimes to such an extent as to obliterate the features. Vesicles form which break and will leave a yellow scab. In these cases there is some fever, increased pulse, severe headache, itching and burning, nervous twitching, burning in the throat and mouth, thirst, rheumatic pains, which are aggravated by heat and rest, cough, nausea, vomiting, perhaps chilliness and even delirium. If toxic doses are taken internally symptoms are similar to above; but there is according to the dose taken drowsiness, stupor, flushed face, dilated pupils. Pulse which may have been strong will become small, feeble and rapid; respiration becomes hurried, nausea, vomiting, delirium and even convulsions result. It relieves cerebral engorgement by increasing the tone of the arteries. In small doses it tones the weakened brain, acting as a sedative. Its effect is most pronounced on the terminal nerve filaments, increasing their function. In large doses overstimulation results, followed by relaxation if carried too far.

Indications: Sharp, hard pulse; sharp burning pain, burning pain in frontal region, especially over left orbit; tongue showing small red points on upper surface of tip; cough with burning pain in chest; restlessness, starting and crying out during sleep. Extreme redness of local part with sharp, burning pain. Itching and tingling in the skin. In fact burning pain is a prominent indication.

Use: In fevers, inflammation and any condition where indicated. Its action is on the nerve centers, producing functional activity of the terminal nerve filaments. It relieves cerebral engorgement by giving tone to the arteries. In small doses it acts as a sedative to the irritable and often overworked brain, improving its function and tone. We think of it in erysipelas, eczema, typhoid fever, cerebro-spinal meningitis, cerebral irritation; in scarlet fever, measles, smallpox, gastric and intestinal irritation, especially if accompanied by restlessness; spasms in children the result of cerebral engorgement. In rheumatism of the chronic or subacute form where the white fibrous tissue is involved, therefore pain more severe when at rest, it is of value. In cholera morbus, cholera infantum in which there are pronounced head symptoms it is of value, if associated with other indicated remedies. We find it very useful in many conditions of gastric irritation. In swelling of submaxillary glands when there is induration it has been used with success. Rhus tox. is a valuable remedy when indicated.


The Materia Medica and Clinical Therapeutics, 1905, was written by Fred J. Petersen, M.D.