Arbor Vitae, Thuja Occidentalism one of the Coniferae, a form of cedar, incorrectly called White Cedar. The true white cedar is Cupressus thyoides.

Thuja contains a volatile oil called oil of arbor vita in about 1 per cent in the fresh leaves, and it (the oil) contains dextro-pinene as its active agent. There is considerable resin, some wax, a bitter principle, a yellow astringent body, and aromatic principles in thuja.

Thuja is a terebinthinate and partakes of the characteristics of the terebinthinates generally, which are presented under "Abies," q. v. The terebinthinate thuja most resembles is savin, one of the junipers. See "Sabina." Naturally, therefore, thuja is an irritating stimulant and astringent, an aromatic, diuretic, and (in large doses) an irritating emmenagogue. The oil is toxic and induces violent gastro-enteritis and genito-urinary inflammation.

Therapeutics

In medicinal doses thuja is a very useful terebinthinate. Like all terebinthinates, it is contraindicated in acute inflammatory states, especially of the urinary organs; but in chronic and subacute prostatic troubles, incontinence of urine, spermatorrhea, gonorrhea, vesical atony, etc., thuja is often useful. It is one of the most satisfactory terebinthinates because the dose is small in these indications - 3 to 10 minims of the fl. made from the fresh leaves. It may be given on sugar. Never give the oil internally.

But the local uses of thuja are the more important. It is one of the best of agents to repress fungous granulations and warts, even the so-called venereal warts; and flstulae, papillomatae, bleeding moles, nevi, "soft chancres," fissures, urethral carbuncles, and many other indolent lesions may have the fl. applied full strength if upon the skin, and 1-5 to 1/2 strength (diluted with glycerine) if upon mucous membranes. Of course surgical and other local attention should not be neglected.

A non-alcoholic thuja is prepared. It is an astringent miscible with petrolatum, and is used to a limited extent in the treatment of indolent affections of the mucous membranes, from one part in eight of petrolatum up to full strength.