BPS 1101 Study Guide - Midterm Guide: Aspirin Poisoning, Elixir Sulfanilamide, Coal Tar
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Introduction and History
Science vs. Magic
oDraw conclusions based on those facts.
oTest your conclusions in several ways.
oDraw the conclusions you want.
oFind some facts to fit those conclusions.
oAvoid testing or challenging your conclusions.
Life Expectancy (2009)
We see longer life spans and improved quality of life.
Canada had one of the highest standards of living in the world (81.2 years of life).
The world life span is much lower than that of Canada (66.6 years of life), but it is still almost double in
comparison to most of human history.
In some countries, the life span is actually lower than the life expectancy in the stone-age (Swaziland: 31.9 years of
Life Expectancy through History
Life span is an educated guess based on written records and archaeology.
It is important to remember that only “important” people make it into historical records.
oLife expectancy, however, is mostly the “ordinary” people.
Life expectancy was approximately 30-35 years for most of recorded history from about 500,000 to 6,000 years
ago, and was so even in the last 6,000 years.
According to data for the United States, 150 years ago, life expectancy was the same as that of the stone-age.
oMost of the improvements in life span have happened over last 150 years, after 1850 which was around
the time when the scientific approach began to take form.
Improved Quality of Life Today
1900: 44 years.
oMain causes of death (lasted until the 1950s):
2004: 82 years.
oMain causes of death:
Lower respiratory infection.
Life expectancy has doubled in the last 100 years because of the changes in the quality of life.
Causes of death have shifted from infectious disease to “wear and tear”.
Historically, people lived their entire lives in an unhealthy state and they were constantly sick (parasites).
oThese conditions still exists in many developing countries.
Main Reasons for Improved Health
oSewers went from being opened to closed.
oPopulations were not longer being exposed to the dead.
Clean drinking water.
oSafe water supply.
oDrinking water makes Guinea worms (dracucculiasis) in the body migrate to the muscles and exit the
oA major improvement was chlorination since chlorine removes bacteria that leak into the water.
oFood spoilage was common before this, but now there is modern food storage year-round.
Greatest Achievement in Medicine
oVery successful for viral diseases.
oEliminated in 1977.
oOnly exists in labs and biological weapons.
oGene sequence online.
oThose that were vaccinated before 1972 were left with a scar.
oEradicated from North America in 1991.
oThere are currently less than 1,000 cases worldwide in 10 or 11 countries.
oThe major eradication barrier is politics.
Penicillin reduced maternal mortality rates.
North American Drug Market (2009)
Prescription drugs: $300 billion.
Over-the-counter (OTC) drugs: $25 billion.
The USA consumes almost half of the world drugs (49.1%) whereas Canada only consumes 3.8%.
Most Ancient Medications Were Useless
These medications were just “made-up” cures that were accepted because people liked to believe in magic.
They claimed they felt better just by getting treatment.
Only a small number of treatments actually worked and a few of these are still used today.
Most ancient drugs came from plants.
Plants use chemicals to protect themselves and we use these poisonous substances as medicines.
Drugs are Poisons
Drugs: Produce desired (beneficial) biological effect.
Poisons: Produce undesired (harmful) biological effect.
The difference between a drug and a poison is the dose.
oSola dosis facit veneum: Only the dose makes the poison.
The Greek word for both poison and drug is pharmakon.
Normally we assume that low doses produce beneficial effects (drug) and high doses produce harmful effects
(poison), but sometimes low doses produce harmful effects (poison) and higher doses produce beneficial effects
oAsk “how much”?
How Were Drugs Discovered?
Observation and experimentation (rare):
oPeople observed the effect of the drug.
oStrong poisons (common) in a low dose made it into a drug and was easily identified.
oWeak poisons (uncommon) required a large quantity for effect.
Philosophy (very common):
oThis was based on belief.
oA cure would be arrived at by reasoning.
oHealing was often connected with superstition, magic, and religion.
This was and old Egyptian document that describes plants and their medicinal treatments.
He was the father of medicine and promoted experimental methods – testing and observing cures instead of making
oHe tried to reject superstition and religion from healing.
Ox liver for night blindness.
Poppy juice for crying babies.
Animal fat for baldness.
Identification of Opium for Pain
Opium is extracted from poppy seeds (easy to find in nature) and can be used as a narcotic painkiller/sedative.
It is toxic in high doses, but is a drug in low doses.
Identification of Cocaine as a Stimulant
From observation, cocaine was found to be a topical painkiller/stimulant.
It is extracted from cocoa leaves.
In the past, Coca-Cola used to contain cocaine, but now it doesn’t.
Quinine as a Malaria Treatment
Malaria is the second infectious killer in the world.
Quinine is derived from Peruvian bark which was once more valuable than gold.
It is a bitter substance that is mixed with alcohol and gave rise to gin and tonic.
Problems with Observation
The human brain searches for patterns even when they are not there.
Ancients did not use experiments or statistics, but simply relied on their own experiences.
Anecdotal evidence is unreliable because it relies on change.
oThe drug and effect may be coincidental (medication and cure/poison and harm).
oPerceptions are subject to placebo effects.
Once “evidence” is available, it is hard to contradict and many harmful remedies are retained because of this.
Apophenia: Seeing patterns or connections in random or meaningless data even when they are not there.
Pareidolia: Perceiving sounds or images as something else such as human faces and letters.
Only Experimental Evidence is Reliable
You make a measurement properly and accurately.
You must rely on statistical significance by collecting data from a large number of experiments and then looking
for averages and trends.
Problems with Traditional Remedies
There is poor control over dose since plants produce variable amounts of active ingredients.
Preparation of things changes their chemical compositions.
oRaw and cooked foods have different chemical patterns.
There was no standardization and no instructions.
oInformation was passed verbally which could have made it imprecise and resulted in poor reproducibility.
Now things come with standard instructions that increase reliability.
Philosophy to Identify Cures
A cure is arrived at by reasoning which often equates to it being made up.
People would search for “proof” afterwards.
Healing is often connected with superstition, magic, and religion.
Hippocrates Develops Doctrine of Humours
The universe is made up of four elements: earth (dry), air (cold), fire (hot), and water (wet).
He built on these ideas and this dominated medical theory.
The body is made of four humours: blood (cold), phlegm (wet), yellow bile (hot), and black bile (dry).
The four humours are normally in balance, but when there is too much or not enough of one of them, it causes
oThe cure for this is the re-balancing of the humours.
oA diagnostic could be made by using the properties of the humours.
E.g. Fevers are associated with hot and dry therefore, the cure would involve using cold and wet.
Bloodletting and the Doctrine of Humours
You would re-balance the blood humour by taking different volumes of blood (bloodletting).
However, removing blood may not be beneficial since everyone needs it to survive.
The treatment was often worse than the disease and would kill the patient.
oGeorge Washington was killed due to loss of blood from bloodletting.
Sometimes leeches were used to suck out blood or emetics and purges would be used to try and gain a rebalance.
These treatments were often done randomly.