B1.3 Drug use / Abuse Flashcards
What are the main differences between viruses and bacteria?
Bacteria are living cells that produce toxins that damage cells in the body
Viruses invade cells and replicate themselves, they cannot be seen with a microscope
How is the body adapted to fight disease?
Skin as a barrier
Cilia and mucus
Blood clots to seal wounds
White blood cells producing antibodies and anti toxins
How to white blood cells prevent illness?
An invading cell will have unrecognised antigens on its surface
The white blood cell produces new antibodies that are able to fit on these antigens and destroy the pathogen
The white blood cell can now remember this antibody and it is readily available if the pathogen tries to infect the person again.
How do vaccines immunise a person against disease?
The body is injected with a small amount of dead or inactive pathogens. These pathogens carry antigens and, despite being harmless, cause the body’s white blood cells to produce antibodies to eliminate them. The production of antibodies creates immunity against that pathogen in the future as white blood cells are able to recognise them quickly.
What are the three main stages of drug testing?
- Drugs are tested on computer models or human cells grown in the lab
- Drugs are then tested on animals
- If they pass, clinical trials begin using healthy volunteers and low (growing) doses
What is a double blind trial?
Some patients are given the drugs and others are given the placebo
Neither the doctors or the patients know who had the placebo or the real drug until the trial is over
What is the placebo effect?
A patient feeling better through the power of suggestion that they should feel better rather than the drug working
The effect of this on the trials can be minimised with double blind trials
What is Thalidomide?
A drug misprescribed to pregnant women because they thought it would ease morning sickness
It caused the stunt in growth of limbs of unborn babies that affected 10,000 babies around the world
What was thalidomide orginially used for?
A sleeping pill
What is thalidomide used for today?
It is now used as a treatment for bone cancer and leprosy
It is heavily regulated and trials of any drug are now strictly monitered
What can cause people to become dependent on a drug?
The drug can change the chemical processes of the body and cause the person to feel withdrawal symptoms if they do not take it
They develop receptors for the drug
Is alcohol a depressant or a stimulant?
Alcohol is a depressant meaning it slows down signals in the nerves and brain
What are the negative side effects of alcohol?
- Unconsciousness / comatose
- Addiction
- Liver / Brain damage
- Weight gain
How many deaths are due to smoking each year?
114,000
What part of the cigarette is addictive?
Nicotine
