1.8 + 1.9 Antibiotics and painkillers + Discovery and development of drugs

Heart drug digitalis

Originates from foxgloves

Painkiller aspirin

Originates from willow

antibiotic penicillin

was discovered by Alexander Fleming from the Penicillium mould

Traditional vs modern drugs

Traditionally drugs were extracted from plants and microorganisms.Most new drugs are synthesised by chemists in the pharmaceutical industry. However, the starting point may still be a chemical extracted from a plant.

New drugs

New medical drugs have to be tested and trialled before being used to check that they are safe and effective. They are extensively tested for:
toxicity - side effects?
efficacy - does it work?
dose - correct dosage

Preclinical testing

Is done in a laboratory using computer models, cells, tissues and live animals.

clinical trials

Clinical trials are a long process, need lots of volunteers and have lots of control variables

Stage 1

* Very low doses of the drug
* healthy patients
* test for side effects.

Stage 2

* If the drug is found to be safe
* patients with disease
* check if it works (efficacy)
* check for side effects
* find the optimum dose for the drug.
* In double-blind trials, some patients are given a placebo and neither patient nor the doctor knows who has the drug.

antibiotic resistance

Caused by overuse of antibiotics, failing to complete the fully prescribed course by a doctor and use of antibiotics in farming

Double blind trial

Neither the doctors or patient know if they are receiving a placebo or the actual drug. Eliminate unconscious bias.

why are some patients injected with a placebo

for a control to compare effects with and without the treatment

peer review

All new drugs must be peer reviewed