NIYUG-NIYOGAN, ampalaya, lagundi, and sambong. These are just some of the herbal medicines that our ancestors used as traditional medicines. Now with long folkloric usage, accumulation of anecdotal evidence, and increasing documentation of scientific studies about their effectiveness, medicinal herbs are regaining wide public and scientific interest.
Herbal drugs consist of plant products that may be whole plants (nonwoody plants botanically referred to as “herbs”) or parts of plants (like ulasimang bato herb, bayabas leaf, niyugniyogan seed, and luya rhizome). These may be parts of woody plants (barks of dita and duhat) or miscellaneous plant products such as secretions (gums, fixed and volatile oils), exudates (oleoresins and resins), and juices (of akapulko leaf and sabila). Herbal drugs are often used to treat chronic diseases or to attain or maintain improved health condition.
Herbal medicine, also referred to as traditional medicine, is practiced throughout the world and has developed into a science-based practice (termed phytotherapy) in some European countries. In Germany, herbal medicines have a special status beginning with the Imperial Decree of 1901 that permitted the trade of many botanical drugs outside pharmacies. Through the following years, drug laws were passed requiring a review of all conventional drugs as well as phytomedicines in the market at that time to assure that they met appropriate standards for quality and purity.
Very few, if any, herbal drugs from Philippine priority medicinal plants have been standardized, hence their quality is very variable. Thus, it is difficult to establish specific doses. In many herbs, the therapeutic potency and potential toxicity of the active constituents are rather low. Further, the percentage amount of these active principles in the plant sources is also low, hence precise dosage is often unnecessary. It is this low therapeutic potency, accompanied by reduced side effects, that makes herbs more useful in treating mild or chronic complaints than for rapidly healing acute illnesses. However, the WHO cautions that in some cases, we can not fully rely on the absence of any evidence of risks during long-term use to indicate that a medicine is harmless. In recent years, there has been concern over the long-term hazards of some herbal medicines.
Evidence is accumulating that various effects result from the multiple constituents in herbal medicines acting in combination, in harmony, and possibly in synergy with each other. Whole herbal drugs or their total extracts may continue to be used with confidence, instead of assuming that a single chemical entity is responsible for the effect. Thus, rather than concentrate on isolating or extracting a single chemical or chemicals from herbs to develop drugs, modern research on herbal drugs and botanical dietary supplements must focus on establishing an adequate science base to support definitive clinical trails. Clinical studies of herbal medicines are needed to first, ensure general safety then to determine efficacy, and second, for post-marketing surveillance to ensure that no serious adverse reactions will develop and to confirm long-term efficacy.
