1 / 49

Chapter 35 Drugs

Chapter 35 Drugs. 35.1 Introducing drugs. 35.2 Anti-acids. 35.3 Analgesics. 35.4 Problems with drugs. 35.5 Hazards of cigarette smoking. 35.6 Working towards a smokeless Hong Kong. CONTENTS OF CHAPTER 35. 35.1 INTRODUCING DRUGS MEDICINES AND DRUGS

asis
Télécharger la présentation

Chapter 35 Drugs

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 35 Drugs 35.1Introducing drugs 35.2Anti-acids 35.3Analgesics 35.4Problems with drugs 35.5Hazards of cigarette smoking 35.6Working towards a smokeless Hong Kong CONTENTS OF CHAPTER 35

  2. 35.1 INTRODUCING DRUGS MEDICINES AND DRUGS Medicines are substances used to cure or prevent diseases. Most medicines consist of one or more drugs. A drug is a substance which changes the state or function of the human body. Alcohol, Milk of Magnesia, aspirin and penicillin are common examples. 35.1 INTRODUCING DRUGS

  3. COMMON TYPES OF DRUGS Drugs fall into a number of types. Anti-acids The word anti-acid means ‘opposite to acid’, often abbreviated as antacid. Anti-acids relieve stomach trouble. They act by neutralizing excess acid in the stomach. 35.1 INTRODUCING DRUGS

  4. Figure 35.2 Milk of magnesia is an anti-acid. 35.1 INTRODUCING DRUGS

  5. Analgesics Analgesics are painkillers, that is, they relieve pain. Figure 35.3 Panadol is an analgesic. 35.1 INTRODUCING DRUGS

  6. Antibiotics Antibiotics are used to treat bacterial infections. Figure 35.4 Keflex is an antibiotic. 35.1 INTRODUCING DRUGS

  7. Anti-histamines Anti-histamines are used to treat allergy. They are effective in relieving hay fever and allergic rashes. Figure 35.5 Polaramine is an anti-histamine. 35.1 INTRODUCING DRUGS

  8. Hypnotics Hypnotics cause sleepiness. Figure 35.6 Barbiturates are hypnotics. 35.1 INTRODUCING DRUGS

  9. Tranquillisers Tranquillisers are substances which relieve tension and anxiety. Figure 35.7 Valium is a tranquilliser. 35.1 INTRODUCING DRUGS

  10. A35.1 Penicillin is an effective antibiotic. It has saved many lives from bacterial infections since the 1940s. 35.1 INTRODUCING DRUGS

  11. 35.2 ANTI-ACIDS WHAT ARE ANTI-ACIDS? We can take anti-acids to neutralize the excess acid in the stomach. They usually contain chemicals such as:  magnesium hydroxide  aluminium hydroxide  magnesium carbonate  calcium carbonate  sodium hydrogencarbonate 35.2 ANTI-ACIDS

  12. Figure 35.8 Anti-acid tablets. 35.2 ANTI-ACIDS

  13. A35.2 Dyspepsia (or indigestion): difficulty in digesting food Heartburn: a burning feeling just below the heart, caused by indigestion Acid stomach: too much acid (gastric juice) produced in stomach, causing pain Flatulence: Uneasy feeling caused by gas generated in the alimentary canal 35.2 ANTI-ACIDS

  14. MAGNESIUM HYDROXIDE/ ALUMINIUM HYDROXIDE AS ACTIVE INGREDIENT Magnesium hydroxide is slightly soluble in water, forming an alkaline suspension. It can thus neutralize the hydrochloric acid in stomach: Mg(OH)2(s) + 2HCl(aq)  MgCl2(aq) + 2H2O(l) 35.2 ANTI-ACIDS

  15. Figure 35.9 Magnesium hydroxide is the active ingredient of Philips’ Milk of Magnesia. 35.2 ANTI-ACIDS

  16. Activity 2 Brief guidelines for the project are as follows: A. To find the best buy according to greatest ‘neutralizing power’ per unit dollar B. Comparison of the actions and side-effects on the active ingredients 35.2 ANTI-ACIDS

  17. C. Other comparisons • Size of packet • Packaging • Appearance of tablet (colour, size, shape etc.) • Instructions to users on safe administration of drugs • Availability in local market D. Conclusion Based on comparisons in Parts A, B and C, decide, as objectively as possible, which brand of anti-acid tablets is of the best buy. Give your reasoning. 35.2 ANTI-ACIDS

  18. CARBONATE / HYDROGENCARBONATE AS ACTIVE INGREDIENT Carbonates or hydrogencarbonates neutralize acid in stomach rapidly. MgCO3(s) + 2HCl(aq)  MgCl2(aq) + CO2(g) + H2O(l) NaHCO3(s) + HCl(aq)  NaCl(aq) + CO2(g) + H2O(l) However, the effect is only short-lasting. 35.2 ANTI-ACIDS

  19. Figure 35.10 Magnesium carbonate and sodium hydrogencarbonate are the active ingredients in this brand of anti-acid. 35.2 ANTI-ACIDS

  20. ‘Bismag’ antacid tablets react with dilute hydrochloric acid. 35.2 ANTI-ACIDS

  21. 35.3 ANALGESICS WHAT ARE ANALGESICS? Analgesics (or painkillers) are drugs to relieve pain. The active ingredient in common analgesics is usually one (or sometimes both) of the following compounds: Aspirin Paracetamol (also called acetaminophen) 35.3 ANALGESICS

  22. Figure 35.12 Some brands of analgesics. 35.3 ANALGESICS

  23. (a) (b) (c) Figure 35.13 Common analgesics contain aspirin and/or paracetamol (acetaminophen) as the active ingredient. (a) Aspirin and Cortal contain aspirin. (b) Panadol, Tylenol and Saridon contain paracetamol. (c) Exedrin contains both aspirin and paracetamol. 35.3 ANALGESICS

  24. THE WONDER DRUG — ASPIRIN Aspirin is the drug which is most widely used as a medicine. It relieves pains (e.g. headache, toothache), and can reduce fever (due to infectious diseases and colds) and inflammation. Aspirin is the common name given to acetylsalicylic acid or sodium acetylsalicylate. 35.3 ANALGESICS

  25. Figure 35.17 Beautiful willow trees. Aspirin was first made from willow bark. 35.3 ANALGESICS

  26. Figure 35.18 Formulae of the two forms of aspirin. 35.3 ANALGESICS

  27. Figure 35.19 One brand of soluble aspirin. 35.3 ANALGESICS

  28. 35.4 PROBLEMS WITH DRUGS SIDE EFFECTS OF DRUGS Drugs may have undesirable side effects. Let us look at some examples. Aspirin irritates the stomach. Some cough mixtures contain codeine. These may cause drowsiness and possible addiction. 35.4 PROBLEMS WITH DRUGS

  29. Figure 35.21 This cough mixture contains a little codeine. 35.4 PROBLEMS WITH DRUGS

  30. A35.3 We should take aspirin after meal, together with a lot of water or milk. DRUG ABUSE What is drug abuse? Drug abuse includes the following:  Obtaining and using drugs (which should be prescribed) without a doctor’s prescription.  Taking drugs for no medical reasons. 35.4 PROBLEMS WITH DRUGS

  31. Taking drugs exceeding the recommended dosage.  Taking a hypnotic or tranquilliser continually for a long period of time, without a doctor’s guidance.  Sniffing solvents (e.g. glue, thinner, petrol).  Taking illegal drugs (e.g. cannabis, cocaine, heroin and LSD). (This is particularly dangerous and will surely lead to early death.) 35.4 PROBLEMS WITH DRUGS

  32. Figure 35.22 Some commonly abused drugs in Hong Kong. 35.4 PROBLEMS WITH DRUGS

  33. DRUG DEPENDENCE A person addicted to a drug is either physically or psychologically dependent on the drug, or both. Physical dependence Psychological dependence 35.4 PROBLEMS WITH DRUGS

  34. Activity 4 The following guiding questions may be useful for this discussion: (1) What are drugs? (2) What are the main types of drugs and their uses? (3) What are the side effects of drugs? (4) What is drug abuse? (5) What are the harmful effects of drug abuse? (6) Is drug abuse serious in Hong Kong? 35.4 PROBLEMS WITH DRUGS

  35. HARMS OF DRUG ADDICTION Harm to drug addicts themselves Harm to families of drug addicts Harm to society DRUG ABUSE IN HONG KONG In recent years, there has been a rising trend in the number of young people taking illegal drugs. 35.4 PROBLEMS WITH DRUGS

  36. Figure 35.23 Government posters against drug abuse. 35.4 PROBLEMS WITH DRUGS

  37. 35.5 HAZARDS OF CIGARETTE SMOKING SMOKING CAN KILL You may have seen many times the government health warning: ‘Smoking can kill’. This warning is no exaggeration at all. 35.5 HAZARDS OF CIGARETTE SMOKING

  38. Figure 35.24 Hong Kong Government health warning: ‘Smoking can kill.’ 35.5 HAZARDS OF CIGARETTE SMOKING

  39. Figure 35.25 A government anti-smoking poster. 35.5 HAZARDS OF CIGARETTE SMOKING

  40. TRAPPING CIGARETTE SMOKE We can trap smoke from a lit cigarette using a ‘cigarette smoking machine’. 35.5 HAZARDS OF CIGARETTE SMOKING

  41. Figure 35.26 A ‘cigarette smoking machine’. 35.5 HAZARDS OF CIGARETTE SMOKING

  42. Experiment results show that high-tar cigarettes without filters give out more tar than low-tar cigarettes with filters. Besides, smokers inhale more harmful substances than passive smokers do. HARMFUL SUBSTANCES IN CIGARETTE SMOKE Smoking produces more than 4000 chemicals. The main products are:  Gases (or vapours)  Carbon dioxide Carbon monoxide Polycyclic aromatic hydrocarbons (PAHs) 35.5 HAZARDS OF CIGARETTE SMOKING

  43. Tar  Nicotine  Particulates 35.5 HAZARDS OF CIGARETTE SMOKING

  44. 35.5 HAZARDS OF CIGARETTE SMOKING

  45. A35.4 Tar. A35.5 6 35.5 HAZARDS OF CIGARETTE SMOKING

  46. Activity 6 Discussion could be based on the following points: (1) Why do people smoke? (2) Should smoking be banned completely? Why? (3) Should smoking be restricted (e.g. in public areas)? (4) If smoking is to be restricted, how should this be done? (5) Should cigarette advertising be restricted? Why? (6) Is restriction on cigarette advertising a violation of freedom of speech? 35.5 HAZARDS OF CIGARETTE SMOKING

  47. (7) Should sponsorship for entertainments from cigarette companies be forbidden? (8) Do you think that the health hazard warnings on cigarette smoking mentioned on cigarette packets and advertisements are effective? 35.5 HAZARDS OF CIGARETTE SMOKING

  48. SUMMARY 1. Adrugis a substance which changes the state or function of the human body. 2. Anti-acidsare drugs that can relieve stomach trouble caused by excess acid in the stomach. Milk of magnesia, with magnesium hydroxide as the active ingredient, is a common anti-acid. 3. Aspirinis a common painkiller, with acetylsalicylic acid as the active ingredient.Panadolis another common painkiller, with paracetamol as the active ingredient. 4. Drugs may have adverse side effects. SUMMARY

  49. 5. Drug abuse is very dangerous. 6. There are two types of drug dependence — physical dependence and psychological dependence. 7. Smoking of cigarettes releases many harmful substances, including:  Carbon monoxide  Polycyclic aromatic hydrocarbons  Tar  Nicotine  Particulates SUMMARY

More Related