This section is from the book "A Practitioner's Handbook Of Materia Medica And Therapeutics", by Thos. S. Blair. Also available from Amazon: A Practitioner's handbook of Materia Medica and Therapeutics.
Causticum is a homeopathic potash preparation much esteemed by the "high dilutionists." It is used by them in arthritic and catarrhal affections marked by burning soreness or rawness. If it really has any true field of action it is in throat troubles with a raw, hoarse cough, where its action would be similar to that of capsicum. Possibly the low dilutions are of some little value in this connection. The mother tincture is irritant, and should be well diluted.
Some singers employ the tablet triturate of this agent to strengthen the voice. Its value is problematic.