Materia medica is a traditional term for what is now considered pharmacology in medicine, but, in National Library of Medicine usage (NLM), refers to "materials or substances used in the composition of traditional medical remedies. NLM has broadened the term to include homeopathic preparations, although it prefers to index them as homeopathy.
Homeopathic materia medica
Materia medica, in homeopathy, are references to the list of remedies. as opposed to repertories giving the indication for using remedies. NLM defines nosodes as specific types of homeopathic remedies prepared from causal agents or disease products. 
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