Definitions [3]
Define:
a. Analgesics
b. Antimicrobials
a. Analgesics: The drugs which relieve pain by acting on the central nervous system without loss of consciousness or disturbance of the nervous system are called analgesics.
b. Antimicrobials:
The drugs used to kill or stop the growth of micro-organisms like fungi, bacteria, and virus are called antimicrobial drugs.
Any chemical substance which, when taken, alters the normal functioning of the body is called a drug.
Psychoactive drugs are chemical substances that act on the central nervous system (CNS) and produce changes in perception, mood, consciousness, cognition, and behaviour.
Key Points
| Type of Drug | Action | Effect on Body | Examples |
|---|---|---|---|
| Hypnotics | Drugs that induce artificial but normal sleep | Cause sleep without major disturbance of consciousness | Phenobarbitone, Diazepam |
| Sedatives | Drugs that produce a calming effect and reduce mental activity | Bring physical and mental relaxation; may suppress consciousness | Cocaine, Opium |
| Narcotics | Drugs that depress the central nervous system and cause sleepiness | Produce stupor, coma, addiction and physical degeneration | Opium, Morphine, Heroin |
| Tranquillisers | Drugs that relieve anxiety and tension without inducing sleep | Maintain consciousness while calming mental state | Diazepam, Lorazepam, Alprazolam |
| Stimulants | Drugs that stimulate the nervous system | Increase excitement, alertness and self-confidence | Amphetamines, Cocaine |
| Hallucinogens | Drugs that cause hallucinations and distortion of perception | Alter personality, sense of time and reality | Cannabis, Mescaline, LSD |
Antimicrobials are drugs that kill or inhibit microorganisms (bacteria, viruses, fungi)
Types of Antimicrobials:
| Type | Where Used | Action | Examples |
|---|---|---|---|
| Antibiotics | Internal use | Selective toxicity (kills microbes, not host); produced by microorganisms | Penicillin, chloramphenicol |
| Antiseptics | Applied to living tissues | Prevent infection (safe for skin) | Dettol, iodine |
| Disinfectants | Applied to non-living surfaces | Kill wide range of microbes | Phenol |
Spectrum of Antibiotics:
| Type | Effective Against |
|---|---|
| Broad spectrum | Many bacteria |
| Narrow spectrum | Specific group |
| Limited spectrum | Single organism |
Cleansing agents are substances used to remove stain, dirt, or clutter from a surface.
Soaps:
- Soaps are sodium or potassium salts of long chain fatty acids
- Obtained by alkaline hydrolysis (saponification) of natural oils and fats with NaOH or KOH
- Reaction: Natural oil/fat + NaOH/KOH → Soap + Glycerol
- Example: Sodium stearate (C₁₇H₃₅COONa)
- Chemically, soaps are triesters of long chain fatty acids and propan-1,2,3-triol (commonly called glycerol or glycerin)
Synthetic Detergents:
Synthetic detergents work in hard water (unlike soaps). Three types:
| Type | Example | Use |
|---|---|---|
| Anionic detergents | (Sodium lauryl sulphate) \[CH_3(CH_2)_{10}CH_2OSO_3^{\oplus}Na^{\oplus}\] | Household detergent, additive in toothpaste |
| Cationic detergents | \[\mathrm{CH_{3}(CH_{2})_{15}-N^{\oplus}(CH_{3})_{3}Br^{\oplus}}\] (Cetyltrimethyl ammonium bromide) | Hair conditioner, germicide |
| Non-ionic detergents |
\[CH_{3}\left(CH_{2}\right)_{16}-COO\left(CH_{2}CH_{2}O\right)_{n}CH_{2}CH_{2}OH\] (an ester) | Liquid dishwash |
 |
liquid detergent |
Concepts [12]
- Chemistry in Everyday Life
- Categories of Drugs
- Drug-target Interaction - Enzymes as Drug Targets
- Drug-target Interaction - Receptors as Drug Targets
- Therapeutic Action of Different Classes of Drugs - Antacids
- Therapeutic Action of Different Classes of Drugs - Antihistamines
- Therapeutic Action of Different Classes of Drugs - Neurologically Active Drugs
- Antimicrobials
- Therapeutic Action of Different Classes of Drugs - Antifertility Drugs
- Chemicals in Food - Artificial Sweetening Agents and Food Preservatives
- Cleansing Agents
- Chemistry in Everyday Life Numericals
