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• Physiological effects of stimulants


  • Increased blood pressure and heart rate
  • Constriction of arteries
  • Dilation of pupils
  • Sweating
  • Reduced appetite
• Amphetamines


  Mimic the effects of adrenaline (epinephrine), the "flight or fight" hormone
• Amphetamine


  A sympathomimetic drug: it mimics the stimulation of the sympathetic system, a structure responsible for subconscious reflexes, by adrenaline
• Structural similarities between adrenaline and amphetamine


  Both have (1) a benzine ring and (2) an amine
• Structural differences between adrenaline and amphetamine


  In adrenaline the amine is primary, while in amphetamine it is secondary. Also, adrenaline contains three alcohol groups, while amphetamine does not.
• Both amphetamine and adrenaline


  Speed up the heart rate and blood pressure
• Short-term effects of amphetamines


  Increase mental energy, reduce appetite and induce a sense of euphoria
• Long-term effects of amphetamines


  Can lead to severe addiction and depression
• Nicotine


  A sympathomimic drug, contained in tobacco leaves
• Short-term effects of nicotine


  • Increased heart rate and blood pressure
  • Reduction in urinen
  • Increased mental alertness and physical energy
  • Constricts blood vessels which puts stress on the heart
• Long-term effects of nicotine


  • Risk of heart disease and coronary thrombosis due to the strain it puts on the heart
  • Risk of peptic ulcers due to excess production of gastric juices
  • Tolerance and addiction
  • Cost to society and family – smokers spend large amount of money on cigarettes
• Caffeine


  Increases frequent urination, concentration and alertness, breathing rate
• Large amounts of caffeine


  Cause anxiety, irritability, sleeplessness (insomnia), addiction and withdrawal symptoms such as nausea
• Historical development of penicillin

  1. Discovery by Alexander Fleming

  2. Isolation and purification by Howard Florey and Ernst Chain

  3. Mass production in the US by growing fungi in large tanks and then by synthetizing the drug
• Penicillin


  Bactericidal, kills bacteria by interfering with the enzymes that bacteria need to form normal cell walls, causing the cell walls to burst and bacteria to disintegrate
• Beta-lactam ring


  A square arrangement of carbon and nitrogen atoms with other atoms attached, common to all penicillins
• Modifying the R-group functional group


  Can make penicillins more resistant to penicillinase, and allow oral administration instead of injection
• Importance of patient compliance and effects of penicillin over prescription


  • Bacteria became resistant to certain kinds of penicillins
  • Harmless and helpful bacteria in the digestive system can be wiped out
  • Bacteria mutate, resulting in "superbugs" resistant to antibiotics, requiring costly development of new antibiotics
• Viruses


  20x smaller than bacteria, not cellular, do not have cytoplasm, do not feed/excrete/grow, use cell material of the invaded cell to reproduce themselves
• Ways antiviral drugs work


  • Prevent viruses from leaving the host cell
  • Block the reverse transcriptase enzyme activity to avoid a conversion of the virus into a form that can enter the host cell
  • Alter the host cell's genetic material, so that viruses cannot use it to multiply
  • Block the enzyme activity within the host cell, so viruses cannot multiply
• Difficulties associated with solving the AIDS problem


  • Antiviral agents are very expensive, making treatment difficult in developing countries
  • Condom use has cultural resistance and high cost
  • Cultural factors like misinformation, ignorance and wishful thinking
  • Illegal activities like drug use and prostitution