Botanical name: 

The spores of Lycopodium clavatum, Linné (Nat. Ord. Lycopodiaceae) or Club Moss, a creeping perennial found in most parts of the earth; gathered mostly in Germany, Russia, and Switzerland.

Description.—An odorless and tasteless, very mobile, light-yellow powder, impervious to but floating on cold water, sinking when boiled with water, and burning with a sudden flash when in contact with flame.
Principal Constituents.—Nearly 50 per cent of greenish-yellow fixed oil; sugar, 2 to 3 per cent, and a trace of monomethylamine (CH3NH2)
Preparation.—Specific Medicine Lycopodium. Dose, 1/10 to 30 drops.
Specific Indications.—Extreme sensitiveness to the touch; urine deposits red sandy or phosphatic particles and readily stains the clothing; water-brash; borborygmus.

Action and Therapy.—External. Lycopodium forms a good protective and absorbent dusting powder for irritated and inflamed surfaces, for which purpose it is largely used in excoriations, intertrigo, herpes, erysipelas, dermatitis, eczema, ulcers, etc. Possessing moisture-repellant qualities it is used in preparing pills of hygroscopic chemicals, to facilitate the manipulation of pill masses, and to keep pills from adhering to each other. It is also employed as the pulverulent base of many insufflations.

Internal. According to Scudder, lycopodium is adapted to disorders showing "extreme sensitiveness of the surface; sensitiveness of a part and care to prevent it being touched; slow, painful boils; nodes or swellings; external sensitiveness of the organs of special sense, with pale, livid, or dirty complexion."

Lycopodium is of much value in obscure forms of malarial fever, with afternoon exacerbations, and deep-red, scanty urine, which readily stains the garments. The fever is not active, but very depressing and intractable, and may be accompanied by sore throat, colic, diarrhoea, dysentery, or constipation. Used according to the specific indications, it is a useful gastric sedative, when in addition there is a sense of fullness and tenderness of the stomach. It often proves effective in pyrosis and fermentative indigestion, with borborygmus.

Lycopodium frequently relieves renal disorders with blood in the urine, and is of service in catarrh of the bladder in adults with painful micturition and gritty concretions. It should be given a fair trial in the lithic acid diathesis, when the passage of urine is attended by pain and red, sand-like particles are voided. The small dose, from the fraction of a drop to five drops of the specific medicine, is the most advantageous form of administration.

The Eclectic Materia Medica, Pharmacology and Therapeutics, 1922, was written by Harvey Wickes Felter, M.D.