Are Radix Rehmanniae's traditional indications supported by current understanding of its pharmacology? A narrative review

By Nicola Anne Scholes

Abstract

Many reviews have been conducted into the pharmacology of Radix Rehmanniae (RR) but these have either not been extensive or have focussed on elements of RR's traditional pharmacology. The herb is described traditionally by Chinese Medicine as having tonic and cooling properties but this means little to the biomedical mind. 

Objectives: 

This study was designed to assess whether the traditional actions and indications are reflected in the known pharmacology of the herb.

Method: 

A thorough assessment of scientific literature resources from the east and west, from 1995 onwards, was undertaken.

Findings: 

Much work has been done but a large proportion of it is not available in English. The areas of tested pharmacological action of RR or its constituents can be classified into blood disorders, cardiovascular disorders, diabetes, neurological disease, kidney disease, cancer treatment, osteoporosis, anti-inflammatory, anti-oxidant, gene expression, immuno-regulation and meletonin deficiency.

Conclusions: 

This review concluded that there is reasonable evidence supporting RR's traditional indications being reflected in the recognised pharmacology of the herb.  Much evidence suggests RR may be useful in particular catalpol one of its ingredients, in neuro-protection in neurological disease.  Anti-inflammatory and anti-oxidant activity is also shown. Gene expression properties are also thought to give RR anti-tumour properties and protection of certain cells during chemotherapy. The review highlights many areas for future research with possible benefits for patients.