A pharmaceutical drug (medicine or medication and officially medicinal product) is any chemical substance formulated or compounded as single active ingredient or in combination of other pharmacologically active substance, it may be in a separate but packed in a single unit pack as combination product intended for internal, or external or for use in the medical diagnosis, cure, treatment, or prevention of disease.
2. History:
The development of small molecule therapeutic agents for the treatment and prevention of diseases has played a critical role in the practice of medicine for many years. In fact, the use of natural extracts for medicinal purposes goes back thousands of years; however, it has only been in the past half century or so that searching for new drugs has found itself in the realm of science. In 1900, one-third of all deaths in the U.S. were from three general causes that are rare today because they are preventable and/or treatable: pneumonia, tuberculosis, and diarrhea. By 1940, the chance of dying from these three causes was 1 in 11; by 2000, the odds were down to 1 in 25.
Of the three, only pneumonia remains in the list of top ten causes of death, which is now led by more complex conditions such as cardiovascular disease and cancer. While other factors such as improved sanitation and vaccination certainly played a role in the increase of life expectancy during the twentieth century – from less than 50 years in 1900 to more than 77 years in 2000 – the availability of drugs to control infection, hypertension, hyperlipidemia, and to some extent even cancer, certainly also contributed to the obvious improvement in our collective health and life expectancy during that period.
The history of drug discovery in the pharmaceutical industry and academic labs over the past half-century shows a progression of discovery paradigms that began shortly after “miracle drugs” such as the penicillins became available to the public after World War