HL CHEM D: Medicine and Drugs

1. HL CHEM D: Medicine and Drugs BY HEIMAN KWOK 12N03S 13.7.14

2. D.1 pharmaceutical products

3. Background Information • The best way to fight disease is by maximizing the effectiveness of the body’s natural defence system, by supplementing our natural healing process • Prevent Entry > Attack Invaders > Immune System

4. Effect of Medicine and Drugs on the functioning of the body • Alter incoming sensory sensations • Alters mood or emotions • Alters physiological states, including consciousness, activity level or coordination • The Placebo Effect - used as a control substance; shows the power of suggestion, or the body’s natural healing

5. NOTE THAT Medicine and Drugs… • May or may not be from doctors or pharmacies • May or may not have beneficial medical properties • From Plants or Fungi in labs or from GMO • Helpful/ Harmful • Legal/ illegal

6. RECOGNISE Categories of Medicine • Infection Fighters: Antiseptics, Antibiotics, Antivirals • Affecting metabolism: hormones and vitamins • Affecting CNS: stimulants, depressants, analgesics (painkiller), anaesthetics (remove sense of felling)

7. Methods of Administration • Oral: taken by mouth – tablets, capsules, pills, liquids, enteric = coating, so its of slow release • Inhalation: vapour breathed in; rapid, anaesthesia smoking – asthma, nicotine and cocaine • Parenteral/ Injection 1. intramuscular (to the muscle) – vaccines; 2. intravenous (bloodstream) – local anaesthetics; 3. subcutaneous (underneath the skin) – dental injections

8. Methods of Administration • Topical: skin patches and ointments absorbed directly from the skin into the bloodstream – hormone treatments such as nicotine patches and oestrogen • Rectal: inserted into the rectum – can be destroyed by acids treatment of digestive illnesses, haemorrhoids • Eye or Ear Drops: liquids delivered directly to the opening – treatment of infections in the eye or ear

9. Lethal Dose • Lethal Dose = dose of a substance in mg per kg of body mass that kills 50% of the sample • The smaller the LD 50, the more toxic the substance

10. Effective Dose • Effective Dose = dose of a substance in mg per Kg of body mass that work 50% of the sample • The smaller the ED 50, the more effective the substance

11. Therapeutic Window • ^ = ratio of the lethal dose to the Effective dose • Therapeutic Effect – the intended physiological effect • Range of a drug’s concentration in the blood between its therapeutic level and its toxic level so the dosage is safe • The wider the window, the safer the substance

12. Stages in Research, Development and testing of new Pharmaceutical Products • Research • Development – purification, working out how it works • Testing – on animals: work out the (effective dose on 50%), also show side effects • Clinical Trials 3 phases - double blinded randomized placebo test on human patients

13. CASE STUDY: Thalidomide • Sleeping aid to combat morning sickness • One isomer of the racemic mixture was harmful • Caused deformations in the babies of pregnant women • Caused by not testing on pregnant mice or having clinical trials on humans

14. Drug Effect • Main Effect: desired • Side Effect: unintended physiological effects • Eg. Morphine for pain relief, however constipation is side effect; or for diarrhea but pain relief as a side effect • Depends on the purpose sought after

15. Tolerance • Over time and regular use, the user needs increasing dosage of a drug to receive the same physiological effect • The user’s dose gets closer to • For some drugs, tolerance develops to one effect of the drug and not to other effects (side) • If the drug is not taken for a long time > decrease in tolerance > overdose • Dependence or Addiction: user becomes dependent on the drug to feel normal and suffers from withdrawal symptoms if the drugs is not taken; eg. Heroin, alcohol

16. D.2 antacids

17. Excess secretion = Gastric Juice • Gastric glands in the lining of the stomach produce HCl which keep the pH of the stomach at 1-2 • Acid environment kills bacteria and provides optimum environment for digestive enzymes • ^ can cause acid indigestion, heart burn/ acid reflux to the esophagus and stomach ulcers

18. Pepsinogen and Pepsin • Pepsinogen forms pepsin in an acidic environment • Pepsin breaks down proteins into amino acids

19. Antacids • Weak bases (not SB as they will burn the gullet) • A remedy, drug that helps combat excess acid by neutralising HCland toning down the pH • Aluminium Hydroxide () • Magnesium Hydroxide () • Sodium Hydrogencarbonate () • Calcium Carbonate ()

20. Antacid Equations CaCO3 + 2 HCl CaCl2 + H2O + CO2 NaHCO3 + HCl NaCl + H2O + CO2 Al(OH)3 + 3 HCl AlCl3 + 3 H2O Mg(OH)2 + 2 HCl MgCl2 + 2 H2O MgO + 2 HCl MgCl2 + H2O

21. Alginates and anti-foaming agents • Some contain alginates which produce a neutralising layer1) produces a neutralising layer on top of acid 2) prevents acid from rising reflux into the esophagus • Others contain anti-foaming agents (dimethicone/ simethicone) which prevents formation of gases and reduces bloating and flatulence as a result of Carbon Dioxide production

22. Antacids Side Effects • Mg compounds cause constipation • Al: laxative or causes diarrhoea • Carbonates: produce Carbon Dioxide causing bloating and flatulence • Because antacids change the pH of the stomach, they can alter other chemical reactions including the absorption of other drugs. They should never be taken for an extended period without medical supervision.

23. d.3 analgesics - painkillers

24. How is pain perceived? • Where you are injured; prostaglandins are produced

25. Ways Analgesics Prevent Pain • Mild Analgesics eg. Ibuprofen, Paracetamol are considered non-addictive: intercept the transmission of pain at the source; indirectly blocks the enzyme-controlled synthesis of prostaglandins • Strong Analgesics (opioids/ narcotics) eg. morphine may have dependence: temporarily binds to opioid receptors sites in the brain and CNS – hence you don’t sense the pain but its still there • Relative value of these two approaches to pain management

26. Derivatives of Salicylic Acid (eg. Aspirin) in Use • Mild analgesic for minor aches and pains to relieve headaches, sunburn pain and pain of arthritis • Anti-pyretic to reduce fever • Anti-inflammatory agent to prevent swelling from injuries • Anti-platelet to prevent clotting by inhibiting the production of prostaglandins, prevents heart disease

27. Aspirin and Paracetamol (non-steroidal analgesics and anti-inflammatory) • Aspirin • Benzene Ring • Ester • Carboxylic Acid • Paracetamol • Benzene Ring • Hydroxol • Amide • Carbonyl

28. Aspirin vs Paracetamol

29. Codeine, Morphine and Diamorphine (Heroin) • P.631 of Brown and Ford • Potent-ness: Codeine > Morphine > Heroin

30. Use of Morphine and its derivatives (Opiates)

31. d.4 depressants

32. Effect of Depressants • Figure 15.9 P.633 • Supresses the brain and CNS • Changes the communication between brain cells by altering the concentration or activity of the chemicals called neurotransmitters • Cause a DECREASE in brain activity which in turn influences the functioning of the other parts of the body such as the heart and breathing rate • (NOTE: analgesics are also depressants)

33. Effect of Use of alcohol

34. Effect of Abuse of alcohol

35. Detection of ethanol in Breath Breathalyser • The alcohol in the blood is realised into the air with the exhaled breath • The alcohol vapour is oxidised by Potassium Dichromate+6 to +3 which then changes from orange to green • The extent of colour change is then measured using a photocell and converted into a percentage BAC mass in grams of ethanol per 100 ml of blood

36. Detection of ethanol in Breath 2 Infrared Spectroscopy with an intoximeter (more accurate) • Causes vibrational motions depending on the mass of the atoms and the length/ strength of the bonds within the molecule • Compares the intensity of IR radiation through the sample with the intensity through air • Does not distinguish between ethanol an propanone which is often present in the breadth o a diabetic patient

37. Detection of ethanol in Blood and Urine • Gas-liquid Chromatography • Blood or Urine is vapourised and injected into a stream of an inert gas (mobile phase) over the surface of a non-volatile liquid (stationary phase) • Components of the vapour including ethanol gas move at different rates depending on their boiling pints and relative solubility in the two phases • Leaving the column holding the liquid phase after a specific interval of time known as retention time • Area under the peak is compared the a known standard in the mixture such as propan-1-ol

38. Synergistic effects of ethanol with other drugs • With Aspirin – causes increased bleeding of the stomach lining and increased risk of ulcers • With other depressants such as barbiturates such as sleeping pills – can induce heavy sedation, possibly leading to coma • With Tobacco – increases the incidence of cancers esp. liver and intestines • With other drugs – interfere with the metabolism by the liver which may cause greater and prolonged effects of the drug

39. Commonly used depressants and structures

40. d.5 stimulants

41. What are Stimulants? • Acts on the brain and CNS • Changes the communication between brain cells by altering the concentration or activity of the chemicals called neurotransmitters • Cause an INCREASE in brain activity which in turn makes the body more alert • Prevent excessive drowsiness through the day and so allow greater concentration and though processes to be possible

42. What are Stimulants? • Results include increased heart rate, blood pressure, wakefulness, restlessness, agitation and insomnia • Results are temporary and then followed by fatigue, insomnia and depression • Sympathomimetic Drug = simulates sympathetic nervous system/ mimics adrenaline

43. Physiological Effects of Stimulants • Facilitate breathing by causing relaxation of the air passages – treatment of respiratory infections such as sever bronchitis • Reduce appetite – treatment for obesity • Cause palpitations or tremors to occur • In excess – cause extreme restlessness, sleeplessness, fits, delusions and hallucinations

44. Adrenaline (Epinephrine) • Released at times of stress ‘flight or fight response’ • Increases heart rate and blood pressure • Increase blood flow to the brain and muscles • Increase air flow to the lungs • Increase mental awareness • Noradrenaline or norepinephrine are similar

45. Amphetamine • Stimulates and enhances the effects of Noradrenaline and Adrenaline • Increases mental alertness and physical energy • Side Effects: dilation of the pupils of the eyes, decreased appetite, possible blurred vision and dizziness • Highly addictive and toxic – rapid development of tolerance and dependence leads to deterioration of body systems • Serious long term effects: severe depression and reduced resistance to infection

46. Nicotine Consumption

47. The biological consequences of smoking LUNGS • Destroyed Cilia • Cough • Mucus collected in lungs • Infected mucus • Infections – Bronchitis • Lung Cancer (caused by carcinogens in tar), Emphysema (reduces surface area of alveoli, inefficient gases exchange)

48. The biological consequences of smoking CIRCULATORY SYSTEM • High blood pressure (caused by nicotine) – • Increased risk for heart attacks • Increased risk for stokes • Blood becomes sticky (increased clotting) • Red blood cells can’t carry oxygen due to carbon monoxide boning with them hemoglobin • Coronary heart disease

49. Effect of Caffeine

50. d.6 antibacterials