what does vaccination involve?
- introducing small amounts of dead or inactive forms of a pathogen into your body to stimulate the white blood cells to produce antibodies.
- if the same live pathogen then re-enters the body, the white blood cells respond quickly to produce the correct anitbodies, preventing infection
herd immunity
-if a large proportion of the population is immune to the pathogen, the spread of the pathogen is reduced
what is an antigen?
- a unique protein on a cells surface
- it induces an immune response in the body
what is an antibody?
-a blood protein produced in response to and countering a specific antigen
what do painkillers do?
-treat the symptoms of disease but do not kill the pathogens that cause it
what antibiotics do?
-antibiotics cure bacterial diseases by killing the bacterial pathogens inside your body
why are antibiotics not the complete answer to the problem of infectious diseases?
- antibiotics do not destroy viruses because viruses reproduce inside cells. It is difficult to develop drugs that can destroy viruses without damaging your body cells
- strains of bacteria that are resistant to antibiotics are evolving
how antibiotics work?
-antibiotics kill the bacteria that cause disease whilst they are inside your body
where were drugs traditionally extracted from?
-plants, for example, digitalis, or from microorganisms, for example, penicillin
who discovered penicillin?
-Alexander Fleming from the Penicillum mould.
a good medicine is:
- effective-must prevent or cure a disease or make you feel better
- safe-must not be too toxic or have unacceptable side effects for patient
- stable-must be able to use medicine under normal conditions and store for sometime
- successfully taken into removed from your body-must reach its target and be cleared from your system once it has done its work
preclinical drug testing in the laboratory uses:
- cells
- tissues
- live animals
drugs that pass animal testing move on to clinical trials
drugs that pass animal testing move on to clinical trials
what do clinical trials use?
- healthy volunteers and patients
- low doses are used to test for safety, followed by higher doses to test for optim does
what is a double blind trial?
- some patients are given a placebo that does not contain the drug and some are given the mew medicine
- neither the doctor nor the patient know who received the real drug or the placebo until the trial is complete
