Standardization of Herbal Drugs


Over the last many years, herbal medicine is becoming an increasingly popular form of healthcare worldwide, as people are turning more and more to nature based treatment of physical ailments and diseases. With a remarkable rise in the consumption of plant-based medicines, more and more pharmaceutical companies are investing heavily in herbal formulations.

Herbal medicine is ages old

Hundred of years ago, our medical treatment was dominated by plant-based medicine. The flourishing of Ayurvedic medicines in India, and Kampo medicine in Japan are some examples. With the increase in synthetic drugs, herb based medicine gradually took a back seat. But in recent years, it has made a big comeback, especially in the Western countries, owing to its comparatively lesser side effects.

Why is standardization of herbal drugs important?

With intense research being carried out in the field of herbal medicine by pharmaceutical giants, it is important at there should be an accepted level of standardization in the process.  A key thrust area for herbal formulations and medicinal plants is the high level of quality assurance. While plants are comparatively safe due to their low toxic levels, their complex composition and chemical constituents require detailed understanding, in order to assess their therapeutic properties accurately. Incorrect herbal authentication, microorganism adulteration and residue of chemical pesticides warrants standardization of herbal drugs. This results in the development of effective and safe herbal medicines.

WHO guidelines for standardization of herbal drugs

With the rapid increase of herbal medicines and the phenomenal expansion of the herbal medicine market, the safety and efficacy of herbal medicines, and the quality of medicinal plants has become a major cause of concern amongst pharmaceutical companies, public health authorities and consumers. The World Health Organization has laid down a set of guidelines for the entire herbal standardization process. This begins with the authentication stage, where different aspects of the plant are examined in detail. Things like regional status of the herb, its taxonomical identity, and histological and microscopical analysis are given special attention. All the collected herbs should be free from foreign matter like animal excreta, body parts of dead insects and loose soil. Evaluating the sensory characters, like odour, appearance, taste and feel, is called organoleptic evaluation. After testing the tissues of diagnostic importance in the herbal drug, the extractive and ash values are studied, along with the determination of moisture content. Further tests are carried out to identify any presence of heavy metals like cadmium and lead, which, when absorbed by the body, are harmful in the long run. It is quite normal for plants to molds and bacteria which come in from the surroundings, resulting in microbial contamination. It is important to detect and remove substances like aflatoxins which result in complicated side effects when consumed along with the drug.

Chromatographic and spectroscopic evaluation

On the basis of the existing chromatographic fingerprint, the testers can accurately assess the quality of the drug. The quantitative and qualitative details of the chief active constituents present in the drug c can be ascertained by applying High Performance Thin Layer Chromatography or HPTLC. This method has a comparatively lesser analysis time, and the process of post-chromatograph derivatization can immediately identify compounds that are non UV absorbing.