**5. Impact of medicinal plants on the pharmaceutical industries in relation to economic growth**

Medicinal plants have played and are still playing an important role in the pharmaceutical industry. Medicinal plants have contributed immensely to the economic growth of many countries through the sales and production of pharmaceutical products. Paul-Marie [29] reported that the annual global sales of drugs were about 300 billion USD. This includes natural product-derived, semi-synthetic and synthetic drugs. Paul-Marie [29] also reported that the global sale of drugs from natural origin varies but as of 1976 it was estimated to be around 5 billion USD and some years later, it was estimated to be around 20 billion USD. This underscores the contribution of medicinal plants and plant-derived drugs to the economic growth of many countries.
