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Uses and Abuses of Drugs


A drug is any substance that affects the way the body and the brain work when it is taken in to the body.

Drugs can be beneficial to the body or harmful to it depending on how we use it. Drugs can be used in many ways. A common example of a drug is caffeine. It is present in tea, coffee, chocolates and some soft drinks.

Medicinal drugs

Medicinal drugs are drugs that are normally prescribed by a doctor. They are used to prevent or cure diseases. They can also be used during surgery and to relieve pain. Antibiotics, painkillers and anesthetics are examples of medicinal drugs.

Antibiotics are chemicals that are widely used to treat many infectious diseases caused by bacteria. Diseases such as pneumonia, tuberculosis and cholera are treated using antibiotics.

In 1928, Sir Alexander Fleming observed that the bacteria he was cultivating on an agar plate could be killed by the mould Penicillium notatum. This led to his discovery of the first antibiotic, Penicillin.

It is important to complete the course of antibiotics prescribed by your doctor even though you feel better. This ensures that all the infection-causing bacteria are killed. If these bacteria are not killed, they may become resistant to the antibiotics. This can cause you to fall ill again.

Antibiotics are not used to treat diseases such as colds and influenza which are caused by viruses. If your doctor prescribes antibiotics when you have a cold or influenza it is to prevent a secondary bacterial Infection.


Painkillers are also known as analgesics. These drugs relieve pain without causing numbness or affecting consciousness. Common examples are paracetamol and aspirin. Aspirin is a stronger painkiller and should only be prescribed by a doctor.


Anesthetics are drugs that cause temporary loss of sensation, making the body unable to feel pain. They are often used in surgeries. Cocaine was the first known anesthetic that caused a loss of sensation in the area where it was injected.

Drug abuse

Drug abuse is the excessive consumption of drugs. This is harmful to the body and has become a very serious problem in many countries. Some common drugs of abuse are heroin, cannabis, methylamphetamine and alcohol.

Drug abusers can become addicted. They become dependent on the drug and feel that they cannot function normally without it.


Heroin is made from the opium poppy plant. Heroin abuse is one of the biggest addiction problems in many countries. It slows down the proper functioning of the nervous and respiratory systems.

Drug abusers who are addicted to heroin display the following signs and symptoms.

  • Tiredness
  • Loss of appetite
  • Very quick addiction to the drug

The effects of heroin intake are as follows:

  • Slowed breathing
  • Weak muscles
  • Dry mouth
  • Dependance on heroin
  • Itching, nausea and vomiting
  • Infection on heart lining and valves

Heroin overdose can be fatal as it can cause failure of the respiratory system. Heroin that is injected into the bloodstream causes collapsed veins, liver disease and respiratory complications.


Cannabis is also known as marijuana. It is obtained from the leaves and flowers of the Indian hemp plant.

Drug users who abuse cannabis display the following signs and symptoms:

  • Dry eyes and mouth
  • Increased hunger
  • Suffer from hallucinations – that is, they may be seeing things that are not there
  • Appear sleepy

Long term health problems that could be caused by cannabis intake are

  • Liver disease
  • Diabetes
  • Depression
  • Anxiety
  • Suicidal thoughts


Methylamphetamine is a colorless and odorless solid which easily dissolves in liquids such as Water and alcohol. During the 1950s, it was used to treat depression and fight fatigue in World War II soldiers. However, scientists soon discovered that methylamphetamine was harmful. Following this discovery, it was no longer used as a medication.

Drug abusers who are addicted to methylamphetamine display the following signs and symptoms:

  • Increased breathing and heart rates
  • Dilated pupils
  • Loss of appetite
  • Heavy sweating
  • Loss of appetite
  • Paranoia/irritability
  • Sleeplessness

Prolonged use of methylamphetamine has been linked to mental illnesses and occasional death from heatstroke, fits and heart attacks.


Another abused substance is alcohol. It is a depressant that slows down brain function. Alcohol is found in many drinks such as beer, wine and brandy. A person addicted to alcohol usually displays the following signs and symptoms:

  • Slurred speech
  • Blurred vision
  • Clumsiness or an inability to walk steadily
  • Withdrawal symptoms when deprived of alcohol

Alcoholics may lose control of their lives as they become dependent on alcohol.