Pharmacognosy is one of the fundamental disciplines of Pharmaceutical Sciences. Like most of the pharmaceutical sciences, it is an applied science and concerns the use of raw materials and substances from natural sources to obtain therapeutic products. The popular use of plants for health care (Phytotherapy) through knowledge from traditional medicine is one of the methods used by pharmacognosy to achieve this end.

The use of natural products as raw materials for new medicines is well established for a long time. These natural products come mainly from microorganisms and plants. Antibiotics, such as erythromycin and tetracyclines, or antitumor drugs doxorubicin and mithramycin were initially extracted from actinomycetes (Fungi). Other known antineoplastic agents, such as vinblastine, etoposide, and taxanes, are secondary metabolites of higher plants. Plant products can be used to obtain isolated structures that can subsequently be modified or used as prototypes for total synthesis or semi-synthesis to obtain drug products that can be approved after successful clinical trials. At Health Canada, such a drug is identified by a DIN (Drug Identification Number).


Sometimes, the isolation of a structure responsible for the effect is impossible as that effect may be due to more than one molecule; in this case, the crude extract or a purified and standardized extract can be used as the final therapeutic product if a promoter can prove by scientific literature that it exists well-documented reviews from clinical data or long traditional uses with success, sufficiently to prove that the product can bring a therapeutic advantage with safety to the user. Such a crude or purified plant product is considered a Natural Health Product and once approved by Health Canada; it is identified by an NPN (Natural Product Number).

In some cases, some herbal products in the form of extracts (contain unisolated molecules whose content varies according to the extraction method) and for this purpose may have the safety profile of a pure drug compound: interaction with other drug products; the effect of such a product can vary according to the state of health of the user. Some compounds present in certain plants, including the group of plant compounds known as alkaloids, may have a high toxicity profile in infinitely small quantities. The reason for this is that plant-based products should be taken with care even as an extract. Please read the indications on the Natural Products label calmly, or consult a qualified health care professional before using any natural product if you have any doubts.