Chapter 16 - The Use and Abuse of Drugs 

Drug

• Drug is an %%externally administered%% substance that alters the metabolism
  • %%Stimulants%%: Drugs which reduce the reaction time. (e.g. nicotine)
  • %%Depressants%%: increase the reaction time.
  • %%Narcotics%%: Addictive drugs

Addiction:

A state if the drug is not taken, the body shows %%physical dependence%% i.e. some signs and symptoms like muscle pain, vomiting and diarrhea called %%withdrawal%% %%symptoms%%.

Antibiotics:

A substance extracted from micro organisms to control %%bacterial infections%%.

1. %%Penicillin%%:

   It is extracted from the fungus called %%penicillium%%. Acts against a wide range of bacterial infections. Many bacterial have become resistant to penicillin today so the new derivatives of penicillin are being used against bacteria.

2. %%Streptomycin%%:

It is obtained from a bacterium called streptomycin.

• Antibiotics work by inferring the enzymes of bacteria involved in protein synthesis.
• They interfere the cell division
• They break down the bacterial cell walls
• Antibiotics %%do not work against viruses%%
• Overdose of antibiotic can have side effects
• If antibiotics are taken less than the recommended dose, bacteria develop %%resistance%% against them.

Types of Drugs:

1. %%HEROIN%%:

   • Strongly %%depressant%%
   • Reduces hunger, so malnutrition can occur
   • Sharing needles can spread infections like aids, hepatitis, etc.
   • It is an expensive drug and user develops tolerance against it.
   • The addict person ignores family and job, so many have limited sources of income, thus they get involved in theft.
   • %%Initially dulls%% the senses and produces %%feelings of well being%%.
   • %%Withdrawal symptoms%% include : watery eyes, stomach upset, muscular pain, vomiting, diarrhea and hallucinations.

2. %%ALCOHOL%%:

   • %%Depressant%% drug
   • Slows down the conduction of %%nerve%% %%impulses%% so increases reaction time.
   • It effects cerebrum causing loss of speech, or a person may become %%unconscious%%.
   • It effects %%medulla%%, it may cause death.
   • Increases acidity in stomach.
   • Can lead to stomach ulcers
   • If an alcoholic is smoker too, it increases chances of %%oral cancer.%%
   • It reduces sperm count, so leads to male sterility.
   • It causes %%vasodilation%% in the skin.
   • It reduces water potential of blood, a person feels thirsty and drinks more water, it can cause kidney failure.
   • It causes %%liver cirrhosis%%
   • For pregnant women, alcohol consumption leads to an %%underweight baby%%
   • %%Withdrawal symptoms%% of alcohol include: Tremors, high pulse rate, sweating, visual hallucinations and restlessness.

3. %%TOBACCO SMOKE%%:

   • %%Carbon Monoxide%%:

     - combines irreversibly with the hemoglobin to make carboxyhemoglobin. It reduces oxygen carrying capacity of blood causing tiredness and breathlessness.

   • %%Irritants%%:

     - stimulate the release of excessive mucus. It blocks the bronchioles and produces a state of difficult breathing called bronchitis.

   • %%Tar%%:

     - deposits on inner lining of alveoli and breaks the elastin surrounding alveoli. This state is called emphysema.

   • %%Nicotine%%:

     (i) stimulant

     (ii) narrows blood vessels

     (iii) makes blood cells sticky

     (iv) increases heart beat

     (v) cardiovascular diseases

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