Vaccination, Antibiotics and painkillers, discovery and development of drugs.

Vaccine definition.

Vaccines are weakened or inactive pathogens which trigger an immune response within the body to aid the body in fighting infections against the real pathogen.

Evaluate how vaccines work to prevent diseases.

• A vaccination basically injects an inactive form of a pathogen into the body. This will activate an immune response and antibody production, which means that memory cells are made. This protects the individual incase the real pathogen enters the blood again.

Name an example of an antibiotic

Penicillin

How do antibiotics work?

They cure bacterial disease by killing infective bacteria inside the body. Bacteria should be treated by specific antibiotics.

What do painkillers do?

Treat the symptoms of disease but does not kill pathogens.

What are the flaws with:

• Antibiotics

• Painkillers

• Drugs to kill viruses

Antibiotics - cannot kill viral pathogens

Painkillers - does not kill the pathogen, only treats it.

Drugs to kill viruses - It is difficult to develop drugs that kill viruses without also damaging the body’s tissues.

Traditionally drugs were extracted from plants and microorganisms.

List some of the drugs we know

• The heart drug - digitalis

• The painkiller — aspirin

• Penicillin

Where did digitalis originate from?

foxgloves

where did aspirin originate from?

willow

where did penicillin originate from?

• discorvered by Alexander Fleming from the Penicillium mould.

1. efficacy meaning

2. What are new drugs extensively tested for?

1. efficacy - the ability to produce a desired or intended result.

2. toxicity, efficacy and dosage.

1. 3 key stages of Clinical drug trials.

2. Explain what happens at each stage briefly.

1. Pre-clinical drug trials

   • Drugs are tested using computer models and human cells grown in the laboratory.

   • This allows the testing for efficacy and possible side effects.

2. Animal trials

   • Drugs that pass the first stage are tested on animals. An amount of the substance is given to the animals and they are carefully monitored for side effects.

3. Human clinical trials

   • Drugs are then tested on humans during clinical trials.

   • First tested on healthy volunteers to check they are safe.

   • Then tested on ill patients. Small doses are used first and the dosage increases until the optimum dosage is identified.

What are double blind trials?

Where patients are given a placebo and neither the researchers nor the patients know if it is the placebo.

Placebo - Doesn’t have any physical effect but is used to see the physiological effects.