This section is from the book "Practical Materia Medica And Prescription Writing", by Oscar W. Bethea. Also available from Amazon: Practical Materia Medica and Prescription Writing.
Latin, Cantharis (Gen., Cantharidis)
Eng., Cantharides. Synonym, Spanish Flies. The dried beetles Cantharis vesicatoria.
Eng., Cantharides Cerate. Contains 35 per cent. of the drug.
Eng., Cantharidal Collodion. Represents 60 per cent. of the drug.
Eng., Cantharides Plaster. Cantharides Cerate and Resin Plaster spread on fabric. Each square centimeter of spread plaster contains 0.1 Gm. of Cantharides Cerate.
Eng., Tincture of Cantharides. Represents 10 per cent. of the drug.
1 1/2 minims (0.1 mil).
Rubefacient, vesicant, and also classed as a diuretic and aphrodisiac, though not used as such.
Sometimes used as a counter-irritant as in the treatment of neuralgia, sciatica, or related conditions. Used in hair preparations to stop loss of hair.
Cantharides is seldom prescribed. The Cerate or Collodion is sometimes ordered for external use to produce counter-irritation.
The tincture is employed with other agents in applications to the scalp. Internally it is almost unemployed.
 
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