Biology B1.3.1 Drugs

A drug is a substance or chemical which alters the way in which the body works.

Medical drugs are developed in stages:

1. An idea for a drug is made in a lab.

2. The drug is tested on cells, tissues and organs

3. It is then tested on animals

4. The drug is tested on healthy volunteers, then sufferers of the target condition.

5. If the drug passes all stages, it is licensed and continually monitored.

Statins are used to lower cholesterol level and are usually taken for a lifetime. They reduce the amount of cholesterol you produce, so your cells take it from your bloodstream. They reduce your level of LDLs and can reduce the risk of heart attack and stroke by a third. However, they can have a negative effect on your kidneys, liver and muscles.

Thalidomide was prescribed as a sleeping pill, but was found to relieve morning sickness during pregnancy. As a result, it was given to pregnant women, but it had not been tested properly and the babies of these people were born with severe limb abnormalities. It lead to more thorough testing of drugs and is now used to treat leprosy.

Alcohol is a depressant. It affects:

• Heart and circulation
• Mental health
• Lungs
• Liver
• Fertility
• Stomach
• Bones
• Intestines
• Pancreas
• Kidneys

It can also cause brain damage, cancer and antisocial behavior.

Nicotine is smoked in cigarettes which contain tar and other chemicals. It affects unborn babies, circulation, the brain, the lungs, skin, fingers and teeth, fertility and the immune system. It can cause emphysema, cancer and heart disease.

Cocaine, Ecstacy and Heroin

• Affect the circulatory system
• Very addictive
• Cause withdrawal symptoms

Cannabis is an illegal drug. Its smoke contains chemicals which can cause mental illness. It affects the brain and has similar effects to nicotine.

Legal drugs have a bigger impact on health than illegal drugs because far more people use them.

Steroids are performance enhancing drugs. They stimulate muscle growth and are illegal. They can cause aggression, liver disorders, acne, hair loss, hypertension, raised cholesterol and tumors.

Experimental - A drug is tried a few times to see what it is like

Recreational - A drug is used regularly but in a 'controlled' way

Dependent - A drug is addictive and your body needs it

Stimulant - Speeds reactions up

Depressant - Slows reactions down