Transcript What is a medicine or drug?

OPTION D
MEDICINES
and
DRUGS
D1: Pharmaceutical products
and short overview of the option
Dr. Ilias Liakatas
Outline of this option
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Jan 3, 2010
Pharmaceutical products
Antacids
Analgesics
Depressants
Stimulants
Antibacterials
Antivirals
Drug action (HL)
Drug design (HL)
Mind altering drugs (HL)
Medicines and Drugs
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What is a medicine or drug?
A substance that alters one or more
of the following:
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Incoming sensory sensations
Mood or emotions
Physiological state
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Consciousness
Activity level
Co-ordination
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Categories of medicines
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Infection fighters
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Affecting metabolism
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Hormones
Vitamins
Affecting central nervous system
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Antiseptics
Antibiotics
Antivirals
Stimulants
Depressants
Analgesics
Anaesthetics
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Placebo Effect
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Inert substance but effective
Used as control substance
Power of suggestion
Body’s natural healing
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Research on new products
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Tests on animals
Dose, side effects
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Clinical trial (phase 1)
Safety, dose range
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Clinical trial (phase 2)
Response, investigator bias, statistics
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Clinical trial (phase 3)
Extended evaluation
> 16/3620 medicines into the market in 1970
> Thalidomide: for morning sickness but deformed babies
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Medicines and Drugs
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Administration of drugs
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Oral
convenient, absorbed at small intestines
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Rectal
when not able from mouth or destroyed by acids
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Inhalation
rapid, anaesthesia
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Parenteral / Injection
Subcutaneous (dental, slow)
 Intramuscular (vaccinations, large V)
 Intravenous (fast, practical)
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Medicines and Drugs
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Lethal Dose (LD50)
= the dose of a substance in mg per Kg of body
mass, that kills 50% of sample
The smaller the LD50,
the more toxic the substance
Examples:
aspirin
nicotine
ethanol
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Medicines and Drugs
rat: 200
rabbit: 1000
rat: 50
rat: 9000
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Effective Dose (ED50)
= the dose of a substance in mg per Kg of body
mass, that is effective to 50% of sample
The smaller the ED50,
the more effective the substance
Examples:
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aspirin
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Therapeutic window
= the ratio of LD50 over ED50
The wider the window,
the safer the substance
Examples:
aspirin
therapeutic window = 200/55
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Medicines and Drugs
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Drug effect
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Main effect (desired)
Side effects (unwanted responses)
Drug effects are relative!!
Morphine:
For pain relief, constipation is side effect
For diarrhoea, pain relief is side effect
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Medicines and Drugs
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Tolerance
Over time and with regular use, the user
requires larger dose of the drug to
achieve the effect originally obtained by
smaller dose
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Increase of hazards (larger amounts)
No tolerance to side effects
If drug not taken for long time >
decrease of tolerance >
overdose
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And now a short
presentation of the rest of
the topics of this option...
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Medicines and Drugs
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ANTACIDS
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Why is stomach acidic?
How can we neutralize it?
What are the most common
antacids?
What are the neutralizing reactions?
With what can the antacids be
combined?
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ANALGESICS
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What are soft and strong
analgesics?
How do they prevent pain?
Aspirin versus paracetamol?
Morphine versus heroin/codeine?
Advantages – disadvantages?
Medicines and Drugs
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DEPRESSANTS
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What is their effect?
How is effect dependant on dose?
Tranquilizers
 Sedatives
 Hypnotics
 Anaesthetics
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Ethanol (effects, detection)
Most common depressants?
Medicines and Drugs
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STIMULANTS
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What is their effect?
Adrenaline versus amphetamines
Nicotine
Short-term effects
 Long-term effects
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Caffeine
Effects
 Comparison to nicotine
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Medicines and Drugs
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ANTIBACTERIALS
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The discovery of penicillin
How penicillin works
Modifications of penicillin
Use and overprescription
Broad versus narrow spectrum
antibiotics
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ANTIVIRALS
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Viruses versus bacteria
How do antiviral drugs work?
What is HIV and what AIDS?
Why is it difficult to fight HIV?
(AIDS prevention methods?)
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DRUG ACTION
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Geometrical isomers can have
different pharmacological effects
Examples: CISplatin – Thalidomide
Optical isomers can have different
pharmacological effects
Examples: Thalidomide
How structural features affect the
pharmacological effect
Examples: Penicillin, heroin
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DRUG DESIGN
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Compound library
Combinatorial and parallel
chemistry
Computer aided drug design
Polarity modification
Chirality modification
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MIND ALTERING DRUGS
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Jan 3, 2010
LSD, Mescaline, Psilocybin, THC
Effects similarities, differences
Legalization of cannabis
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