Drug or medicine is a substance that does one or more of the following:
Alters physiological state – consciousness, activity level, coordination
Alters incoming sensory experience
Alters mood or emotion
The active ingredients in drugs and medicines can be isolated from a plants and animals or synthesized artificially.
Drugs supposed to assist human body’s natural self-healing capabilities.
Placebos are drugs containing no active ingredient, which “fool” the human body into healing.
D.1.2 Outline the stages involved in the research, development and testing of new pharmaceutical products.
The research and development of new medicines is a long and costly process. It usually takes up to 12 years and costs more than $200 million.
1. First the drug must be isolated or synthetized.
2. The drug is tested on animals. LD50 and ED50 are determined.
3. The drug moves to Clinical Trials
a. Human Pharmacology – testing on small group of healthy volunteers for safety
b. Therapeutic Exploratory – evaluates drug’s efficiency and side effects
c. Confirmatory Stage – large-scale testing of drug
4. A local drug regulatory agency approves a medicine and decides whether it will be
5. OTC (over the counter) or on prescription only.
LD50 is a lethal dose necessary to kill 50 percent of animal population. ED50 is an effective dose, one creating a noticeable effect in 50% of animal population. The ratio between LD50 and ED50 is called the Therapeutic Index.
Therapeutic Index = LD50 / ED50
Therapeutic determines a safety of drug. If the therapeutic index of a drug is 10, a person would have to intake ten times more drug than the effective dose for the effects to be lethal. According to the therapeutic index, the researchers decide whether a dosage must be controlled. If TI is