optional module 4: medicinal chemistry

malaria, dengue fever and the zika virus

from the pancreas of cattle to treat children suffering from diabetes.

synthesised using bacteria or yeast to meet the public deamnd

in a laboratory, using chemical reactions to produce and isolate the acrive medicinal agent

from the bark of willow trees,

now made commercially by reacting acetic anhydride with salicylic acid. The product, acetylsalicylic acid, is then isolated from the other product acetic acid and purified from any other contaminants.

drug discovery pre clinical clinical trials (phase I, II, III) review manufacturing phase IV

a laboratory method that involves using robotics to synthesise thousands of different compounds at a time, usually peptides or small molecules. The compounds can then be tested for effectiveness, and then kept for further testing or modification, or discarded. With this highly automated process, large volumes of molecules can be synthesised and tested in a short period of time, but it is more of a trial-and-error approach, resulting in a large amount of molecules made that have no activity. Although it is difficult for scientists to mimic natural processes, combinatorial chemistry is proving to be making new advancements in drug discovery.

where a placebo is offered to one group of patients while the other group recieves the drug

a pill, lotion or injection that does not contain the active ingredient that the drug has, and is used to see if the drug does have a measurable effect compared to not using the drug.

Ingestion by mouth (e.g. pills or syrups). Injection with a syringe under the skin into fat or muscle tissue or bloodstream. Inhalation by mouth or nose (e.g. as with an inhaler or nebuliser). Absorption through the skin (e.g. medicated lotions or stick-on patches). Absorption in the rectum or vagina (e.g. suppositories). Applied into the ear or eye (e.g. drops of prepared solutions).

the medicine to be absorbed by the digestive tract

metabolism

dosage (grams or millilitres) frequency of administeration tolerance of the drug side effects

A slower, time-released method, such as with oral ingestion or a skin patch, can help to keep the levels of medicine in the body lower and more consistent, and avoid dependency.

50% of the population (LD50) divided by the minimum effective dose for 50% of the population (ED50)

50% of the population (TD50) divided by the minimum effective dose for 50% of the population (ED50)

the range of dosages between the minimum amounts of the drug that produce the desired effect and a medically unacceptable adverse effect

the effective window where the dosage of the drug is most active

the dose of the drug that is enough to kill half of the population

upper limit of the therapeutic window

amount of drug given

dosage, tolerance, addictiona nd side effects

the fraction of the administered dosage that reaches the target part of the human body