Download `active` drugs include cocaine from the coca plant

CHAPTER 12
NEW DRUGS AND OLD REMEDIES
In the early 19th century, advances in chemistry enabled scientists to
isolate the active principles from a number of plants that had been used
for centuries as part of various medicinal remedies. The chemistry
laboratory began to replace the physic garden as a source of new
medicines, and scientists started to investigate the association between the
chemical structure of drugs and the ways in which they acted. The first
major advance was the isolation of morphine from opium in the first
decade of the 19th century. Morphine was soon introduced into medicine
as a powerful painkiller and remains in use today. Heroin, [move to
opium chapter?] in the later 19th century, was another drug derived from
opium. Other fascinating examples where ‘old remedies’ were found to
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contain ‘active’ drugs include cocaine from the coca plant and the antimalarial quinine from the bark of the South American cinchona tree.
[Quinine has played an important role in the fight against malaria.] A
further key development for the pioneering chemical-pharmaceutical
industries of the late 19th century was the production of synthetic drugs.
Aspirin, launched in 1899 by the German company Bayer, was a
particularly important example of the newly discovered synthetic drugs
based on the older remedies of the bark of the willow tree and the plant
meadowsweet. The contribution of the development of discovering and
isolating the active principles of plants, and the introduction of synthetic
equivalents, for medicine has been profound.
From opium to morphine and heroin
‘Of all the remedies it has pleased almighty God to give man to relieve his suffering,
none is so universal and so efficacious as opium.’ (Thomas Sydenham, 1624-89)
‘Take all the morphine (or other forms of opium if that disagrees) you want, and don’t
be afraid of becoming an opium drunkard. What was opium created for except for
such times as this.’ (William James (1842-1910) advising his sister, Alice, who has
been diagnosed with incurable breast cancer in 1891)
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In the early 19th century, a young German pharmacist, Friedrich Surtürner (17831841), isolated a raw crystalline alkaline substance from opium, which he called
‘morphium’ – later to be known as morphine. Some suggest that Surtürner named his
alkaloid after the name of the Roman god of dreams – Morpheus. It was not only the
first alkaloid to be extracted from opium, but the first ever alkaloid to be isolated from
any plant. For a time, Surtürner’s morphine, which was more concentrated than raw
opium, was not widely used, though Surtürner himself, tried and tested it on
numerous occasions. He discovered its effects, from euphoria to depression, from
nausea to constipation, and, most strikingly, its capacity to dull pain. He even realised
that morphine did not so much suppress pain as to make the sufferer ‘beautifully
indifferent to it.’ In the 1820s Merck of Darmstadt, Germany, pioneered commercial
manufacturing of morphine for an expanding global market. Surtürner was later
awarded a prize for ‘having opened the way to important medical discoveries by his
isolation of morphine and the exposition of its alkaline character.’
With the introduction of the hypodermic syringe (hypodermic is from the Latin, hypo,
‘under’ and the Greek, derma, ‘the skin’) and hollow needle, developed initially by
the French surgeon Charles-Gabriel Pravaz (1791-1853) and, subsequently the
Scottish physician, Alexander Wood (1817-84) in the mid-19th century, a new way of
injecting morphine was offered to those who could afford to purchase the small
syringes. Even doctors taught their patients how to inject themselves and, though
more expensive than raw opium or laudanum, morphine was easily administered and
able to by-pass the gut and avoid some of the unpleasant gastric effects of opium.
Injecting oneself unobtrusively in public was acceptable and rich users were delighted
to receive gold or platinum syringes in vanity cases initialled by famous jewellers.
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Doctors were happy to offer it to patients for any number of painful complaints. The
therapy became so woven into the fabric of daily medical practice that, as one author
of a standard British medical textbook, William Aitken, proclaimed in 1880: ‘The
hypodermic syringe and the morphia solution are now almost as indispensable
accompaniments of the physician as the stethoscope and thermometer.’ The American
Civil War was the first war in which morphine – both tablets and injectable – was
administered on a massive scale to alleviate the pain of wounds.
By the end of the 19th century, between a third and two-thirds of all habitual morphine
users were health professionals who had easy access to the drug. Florence Nightingale
(1820-1910), who was an invalid and in chronic pain for much of her life after
returning from the Crimean War, remarked on the benefit of the ‘curious little newfangled operation of putting opium under the skin’ which gave her pain relief for 24
hours. Morphine was used as a symptom- and pain-relieving substance rather than as
a curative medicine. It was, however, also offered as a ‘cure’ for opium addiction!
While morphine and another opium derivative, codeine (which was isolated by the
French chemist, Pierre Robiquet (1780-1840) in 1832) are still widely used, today, in
various safe forms for medically-prescribed pain control, another derivative of opium
– heroin – has had a much more disturbing effect on society. In the later 19th century,
with the growing concern about the habit-forming nature of opium and morphine, the
search was on to find an equally effective but non-addictive alternative analgaesic.
The answer, or so it seemed at the time, was a morphine derivative, diacetylmorphine,
which was originally synthesised in 1874 but ‘re-discovered’ and synthesised by Felix
Hoffmann (1868-1946) on August 21, 1897.. Hoffmann worked for the German
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Bayer Company in Wuppertal-Elberfeld Originally founded which by the 1880s had
expanded to support two key scientific departments – pharmacology and
pharmaceuticals. Hoffman was in the former,whose aim it was to come up with ideas
for new drugs. The head of the latter was Heinrich Dreser (1860-1924) and it was his
role to test all new products.
Dreser initially tested diacetylmorphine on frogs and rabbits, then on himself and then
on a few local workers. After a limited number of so-called human ‘trials’, the
potential of the drug seemed boundless. It was decided to call it ‘heroin’ because all
who tried it felt positively ‘heroisch’ (heroic, strong). The head of reasearch, Carl
Duisberg (1861-1935), was caught up in the excitement. Bayer registered the name
heroin in June 1898 and launched it in September 1898. It was quickly recommended
and marketed as ‘completely non-habit forming’ and ‘a safe family drug.’ It was said
to be ten times more effective as a cough medicine than codeine and, at a time when
tuberculosis (TB), whooping cough, and pneumonia were leading causes of death,
even routine coughs and colds could turn out to be serious chronic and painful
infections. Its most popular form was the pastille. ‘Heroin cough lozenges’ were sold
by the million. Heroin was also, initially, advertised as a ‘cure’ for morphine and
opium addiction.
The true habit-forming nature of heroin, however, increasingly became apparent and
by the early 20th century, serious concerns were being voiced over the addictive
nature of this so-called ‘safe’ opioid and cough remedy. People started taking heroin
not just as a medicine but also in search of thrills. In 1913 there was a rash of bad
publicity when heroin-related admissions mushroomed in hospitals across the east
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coast of America. Reluctantly, Bayer decided to stop making the drug and within five
years it had been declared an illegal substance in much of the world. Opium,
morphine and heroin control has become a central issue in national and international
policy-making over the 20th and 21st centuries.
Morphine still plays a significant role in medicine, especially as an analgaesic in
palliative care. [ADD CAPTION ON PALLIATIVE CARE: In 1967, the world’s first
modern purpose-built hospice - St. Christophers Hospice - was opened in south-east
London by Cecily Saunders (1918-2005), a pioneer of holistic care for the terminally
ill. [(See BOX x)] [Add more here from BOX]. Since then, many hospices and
community and home-based palliative care programmes for adults and children have
been founded across the globe. Physical pain relief, using analgaesics, for the patient
is critical but so, too, is emotional and social support, as well as the need to attend to
the immediate family. In the developed world, palliative care is well-established and
is increasingly now extended to help not just the terminally ill (‘end-of-life’ care) but
also all those at various stages of chronic illness to overcome the symptoms and pain
of suffering..
In the poorer countries of the world, there is still a vital gap in this area of medicine.
The availability of orally administered morphine and staff trained in palliative care
are limited, even though these services can be made available at very low cost. The
WHO estimate that 5 billion people live in countries with low or no access to opioid
analgaesics. Each year, ?millions of patients suffer without adequate pain relief,
including 5.5 million patients with terminal cancer. Health professionals are often
faced with the terrible dilemma of having to choose between saving lives and easing
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the suffering of the dying. A number of countries, including Uganda, Botswana,
Ethiopia, Tanzania and Zimbabwe, have recently embarked on home-based and
community health initiatives to fulfil/l this need – especially where infectious
diseases, such as HIV/AIDS and multidrug-resistant TB, along with noncommunicable chronic diseases, like cancer, are posing a double-burden on public
health. It requires the commitment of community health workers to establish a
framework for putting into place and practice local palliative care teams and facilities.
The Worldwide Palliative Care Alliance (WPCA), founded in 2009 to address these
issues, is a global action network whose vision is a world with universal access to
hospice and palliative care.] However, the illegal use of opiates, notably of heroin,
remains a huge global concern with the majority of raw opium now coming from
Afghanistan.
From the coca plant to Cocaine
‘Sherlock Holmes took his bottle from the corner of the mantelpiece, and his hypodermic syringe from its neat
morocco case. With his long white, nervous fingers he adjusted the delicate needle, and rolled back his left
shirt-cuff. For some little time his eyes rested thoughtfully upon the sinewy forearm and wrist all dotted and
scarred with innumerable puncture-marks. Finally he thrust the sharp point home, pressed down the tiny
piston, and sank back into the velvet-lined arm-chair with a long sigh of satisfaction … “Which is it to-day,” I
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[Dr. Watson] asked, “morphine or cocaine?” … “It is cocaine,” he said, “… Would you care to try it?”’
(opening lines of The Sign of Four, 1890, by Arthur Conan Doyle) [check punctuation]
Cocaine, an alkaloid of the coca plant from South America, was isolated in 1860, and
was another drug introduced for a wide variety of medical purposes, including as a
nerve tonic, stimulant, painkiller, anaesthetic and an antidepressant.
The dried leaves of the coca (Erythroxylum coca) bush/plant/ had been chewed, consumed
and smoked by indigenous peoples in Peru, South America, for centuries as part of
religious ceremonies, as a recreational drug, an aphrodisiac, a stimulant, or to ward off
fatigue, cold and hunger. Coca was known to the Europeans with the opening up of the
New World but, unlike tobacco, was not introduced into European society [why not? – too
long to explain!]. By the mid 19th century, botanists began to investigate its medicinal
properties. In 1860, the German chemist, Albert Niemann (1834-61), extracted cocaine, the
main alkaloid contained within the coca leaf, and by the 1880s there was a ‘craze’ for
cocaine. Like heroin, it could be injected into the bloodstream.
The Austrian neurologist and psychoanalyst, Sigmund Freud initially recommended
cocaine as an aid for the treatment of both morphine and alcohol addictions. Cocaine
also proved beneficial for pain control in surgery and dentistry. Hebegan a research
project on cocaine which included self-experimentation, while his friend, Carl Koller,
demonstrated the effectiveness of it in 1884 as a local anaesthetic for eye surgery.
Cocaine was soon taken up by other ophthalmologists. American surgeon William
Stewart Halsted (1852-1922), experimented with cocaine to determine whether it
could be used for spinal (nerve-block) anaesthesia andBecame addicted in the course
of his experiments.
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A synthetic version of cocaine – procaine (‘Novocain’) - was introduced in the early
20th century as a local anaesthetic in dentistry. Today, however, free-base and crack
cocaine have become amongst the most abused of all illicit drugs.
From willow bark to aspirin [– over five thousand years in the making]
In the same fortnight in 1897 that the German drug company, Bayer, produced heroin
they also came up with the formula for one of the most successful painkillers of all
times – acetylsalicylic acid (ASA) or aspirin. Ironically, however, during that same
fortnight, while Heinrich Dreser of Bayer persuaded his team to go ahead with the
production of diacetylmorphine (heroin), he was very reluctant to pursue ASA. ASA
was shelved by Bayer for eighteen months until it finally went into production in
January 1899 as ‘aspirin’. Little is known about the individual roles in asprin’s
development, but what is known for certain is thatthe idea for aspirin was based on
two old medicinal plant remedies – one being the bark of the willow and the other
meadowsweet.
Indeed, the use of these plants as medicines may date back over 5000 years. There are
records from the Sumerian civilization (c. 3000 BC), ancient Egypt, the Greek and
Roman Empires, the pre-Columbian Americas and early modern herbalists describing,
in particular, the therapeutic value of the bark and leaves of the willow tree.
Hippocrates recommended a brew made from willow leaves to treat labour pains.
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Celsus described the benefits of ‘boiled vinegar extracts of willow leaves for the relief
of pain.’
Others continued to experiment with the symptom-relieving properties of the bark of
the white willow tree In 1838, Raffaele Piria (1814-65), an Italian chemist,
successfully prepared ‘salicylic acid’ from the bark’s active ingredient, ‘salicin’. Over
the second half of the 19th century, various forms of salicylate medicines, including
salicin, salicylic acid, and sodium salicylate became widely used by doctors for the
treatment of pain, fever and inflammation. However, their side effects, particularly
gastric irritation, were considerable.
The Bayer pharmacology teamwanted to find a substitute for salicylic acid which did
not irritate the stomach so much. By adding the acetyl group to the salicylic acid (to
become acetylsalicylic acid or ASA), Hoffmann succeeded in creating ASA in a
chemically pure and stable form and making a compound that neutralised the
chemical element of salicylic acid responsible for its acidity. In fact, Hoffmann was
not the first to make ASA. The German chemist, Charles Frédéric Gerhardt (1816-56)
had actually come up with a formula and published his results in 1853, but did not
pursue it. Whether the Bayer team had read his paper we may never know. And, if
Dreser had had his way, the world might have waited another fifty years for aspirin to
see the light of day!
When Dreser was given ASA for testing, he rejected it on the grounds that it would
‘enfeeble the heart’. Indignant and determined, Eichengrün tested it on himself and
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then decided to do his own ‘discrete’ trials. He sent ASA to their Berlin ‘rep’ who
distributed it to a number of Berlin doctors and dentists. The reports of its efficacy
and benefits were glowing. When the reports reached Dreser, he, once again, showed
no interest and scribbled in the margin: ‘This is the usual Berlin boasting. The product
has no value.’
Fortunately, Duisberg, head of research at Bayer, stepped in and ordered a second full
set of trials. After conducting further ‘rigorous’ evaluations (including trying it out on
goldfish)even Dreser recognised its potential and, initially, took much of the credit
(though the discovery of aspirin was later attributed by Bayer to Hoffmann)Bayer
Aspirin was launched in July 1899, its safety advertised by saying that the drug ‘does
not affect the heart’. It was also packaged with heroin! (GOOD>see image[00091585]
QUOTE: ] … one of the most amazing creations in medical history, a drug so
astonishingly versatile that it can relieve your headache, ease your aching limbs,
lower your temperature ... over 25,000 scientific papers have been written about
aspirin [and]… an estimated one trillion little white pills … have been consumed
since it first came into being ... a wonder drug ... something with few equivalents in
the annals of medical science, and one of the most endurably successful commercial
products of all time. ... it’s a product of a roller-coaster ride through time, of
accidental discoveries and intuitive reasoning, of astounding scientific ingenuity,
personal ambition and intense corporate rivalry …’ (Diarmuid Jeffreys, Aspirin: The
Remarkable Story of a Wonder Drug (2005) pp.1-2)]
)]. By the end of 1899, aspirin was being used all over Europe and the USA and it
quickly proved infinitely safer than the habit-forming narcotic equivalents of
morphine, heroin and cocaine.
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In his 2005 book, Aspirin: the Remarkable Story of a Wonder Drug, Diarmuid
Jeffreys traces the subsequent history of aspirin:
‘Its rise to fame would be a complex interwoven process of patent battles and patent
medicines, of medical ethics and advertising, counterfeits, industrial rivalry, secret
agents and competing national interests.’
And so it was! Yet, in spite of its complex and chequered history (during both World
Wars, for example, when supplies of Bayer Aspirin from Germany were cut off the
Allies had to search for alternatives, including Aspro (Australia)and any number of
rival brands and non-aspirin analgesics on the market, aspirin has been a
pharmacological triumph. It is estimated that over one trillion aspirin pills have been
consumed since it was first launched and it is the best known and most widely used
medicine in the world. Indeed, it has also been used out of this world – as every Space
Shuttle carried a small supply!
The mechanism of action by which aspirin works as an analgesic and anti-pyretic was
not, however, understood until the 1970s – the discovery of which three scientists
(John Vane (1927-2004), Sune Bergstrom (1916-2004) and Bengt Samuelsson
(b.1934)) shared the Nobel Prize in Physiology or Medicine in 1982. The benefits of
low doses of aspirin to reduce blood clots and the risk of stroke, heart disease and
death following a heart attack have also only been recognised by medical science in
the past few decades while recent clinical studies have even suggested that aspirin
might protect against certain types of cancer. (See p. x). Polypills, which contain a
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combination of aspirin and other drugs, are now being tried and tested for heart
conditions.
For a painkiller that was almost shelved over a hundred years ago in favour of heroin,
aspirin has had a remarkable impact on medicine. It is deservedly called a ‘wonder
drug’. The full potential of these cheap little white pills may, yet, to be realised. When
the Reverend Edward Stone ‘discovered’ the therapeutic value of willow bark and
wrote in 1763:
‘I have no other motives for publishing this valuable specific, than that it may have a
fair and full trial in all its variety of circumstances and situations, and that the world
may reap the benefits accruing from it…’
Stone could hardly have predicted the effect that some ‘secret’ trials might have on
the subsequent history of aspirin. But then he might well have preferred to name it
‘Asalixin’ after his weeping willow tree!
From the bark of the cinchona tree to quinine
‘But to discourse particularly as to the Cortex’s [Peruvian Bark’s] manner of
operation, I do suppose that the Cortex doth contain in some of its constituent
principles those active parts, which are as destructive to the seminium febrile as
Alkalies are to acids …’ (Charles Goodall (1642-1712), The Virtues of the Cortex,
1680) [check quote]
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Another remarkable story of developing ‘new’ drugs from ‘old’ remedies relates to
the isolation of quinine from the bark of the cinchona tree. Quinine – a drug used to
prevent or treat malaria - was first isolated from the bark of the South American
cinchona tree in 1820 by the French chemists Pierre Pelletier (1788-1842) and Joseph
Caventou (1795-1877). For at least two centuries prior to the production of quinine as
a pure chemical compound, Europeans in South America had already discovered the
healing powers of the bark of the cinchona tree. This tree thrived on the slopes of the
high Andes. There are many stories and myths about the discovery of the indigenous
South American tree in the early 17th century but it was Jesuit missionaries in South
America who were the first Europeans to come upon a treatment for malaria long
before anyone had any understanding of the cause of this disease (. The Jesuits played
a major role in sending the bark from South America to the major ports of
EuropeCardinal Juan de Lugo in Rome, is credited with analysing and promoting the
bark and spreading its fame throughout Europe. Amongst its many different names
one that was used widely was Jesuits’ Powder. Soon large and regular shipments of
cinchona were being sent from Peru and, under supervision of the Jesuits, it was
traded by merchants across land and sea.
The bark was introduced into England in the 1650s, where leader Oliver Cromwell
(1599-1658) called it the ‘Devil’s Powder’ because of its association with the
Catholic Church. He refused to use it despite suffering badly from malaria, which he
probably contracted in the English Fens. . The role of popularising the bark in
England has invariably been attributed to the London physicians, Thomas Sydenham
(1624-89) and Richard Morton (1637-98). However, much to the annoyance of the
elite physicians, it was a ‘quack’ called Robert Talbor (1642-81) who made his fame
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and fortune using a ‘secret remedy’ based on the bark to cure European royals and
nobility. [ADD more on this story? – see my original chapter on Quinine]. In the last
decade of the 17th century the bark was even introduced to China. During the K’ang
His reign (1622-1722), the emperor was suffering from a severe illness – probably
malaria – and was successfully treated by two French Jesuits with the bark.
This precious commodity was heralded by some during the following century as a
‘Herculean antidote’ to the ‘poisonous’ fevers of the marshes and swamps of both
temperate and tropical regions. European botanical explorers trekked across
impenetrable terrain, risking limbs and lives, to reach the forests of the eastern slopes
of the Andes in order to send seeds or saplings of the bark to Europe – often ending in
dismal failure. Malaria, in the 18th century, proved an ever-increasing and intractable
burden for many localities of the world. It was an especially major problem for
missionaries, explorers, colonists, and the military in many parts of the tropical and
sub-tropical world, where a severe form of malaria (now known as falciparum
malaria) threatened. As Europeans began to settle the coasts, penetrate the interiors,
and colonise the lands of Africa and Asia, they were frequently struck down with
tropical diseases, especially malaria. West Africa was a region often typified as
‘White Man’s Grave’. For example, almost half of the British soldiers stationed in
Sierra Leone between 1817 and 1836 died of disease, mostly malaria. [IMAGE:
50153005 TRANSLATION OF CAPTION: Taking the daily dose of quinine by
British Soldiers.]
Cinchona was not able fulfil its early promises in combating malaria on a wide scale.
The bark was often in short supply; it was frequently adulterated; and it was used
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indiscriminately on a range of fevers. With the isolation of the alkaloid, quinine), in
1820 and its discovery as an effective antimalarial agent in the cinchona bark, this
added chemical knowledge led to hope that this new drug would combat malaria.
Further expeditions and botanical explorations into the South American interiors were
undertaken by Clements Markham, Hugh Weddell, Charles Ledger, Richard Spruce,
Karl Hasskarl and others – this time not just to find the cinchona trees producing the
bark but to identify those species with the highest quinine content with the further
expectation of establishing plantations of cinchona in the notoriously malarial
European colonies of Asia and Africa. The need to cultivate and produce the ‘best’
cinchona species with the highest content of quinine remained an obsessive and
tortuous task.
One particularly important species was the Cinchona calisaya, a Bolivian species.
This was the one that was found to have the highest quinine content, but it was also
one of the rarest species. The search for this species led to one of the most tragic
episodes in the history of quinine. Charles Ledger (1818-1905), a British merchant,
and his faithful servant, Manuel Incra Mamani (d. c. 1871), a Bolivian cascarillero
(who made a living stripping the bark from the cinchona trees for export to Europe,
played a major role in this story. In the 1840s, Mamani led Ledger to the most
magnificent group of calisayas. The time was not right, however, to crop the seeds,
and it would be another twenty or so years before Mamani was able to produce the
seeds in their best condition. In April 1865, Mamani walked some thousand miles to
deliver the precious seeds to Charles Ledger who was then in Peru. Charles Ledger
dried the seeds and sent half to his brother, George Ledger [(?xxx)], in London. To
the Ledger brothers’ utmost surprise, the British government rejected their ‘prize’
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offer of this rare and valuable species and, eventually, all George was able to do was
to sell one pound of the seeds to the Dutch government for planting in Java (? then
part of the Dutch East Indies) for a mere 100 guilders (£20 or equivalent to about xxx
now). The rest were sold to an Anglo-Indian, Mr Money, for £50.
Although this species is now known as Cinchona ledgeriana, both Mamani and
Charles Ledger had sad ends. [Good image of Mamani] Mamani, in an attempt to
collect more seeds to smuggle across the Bolivian border, thus threatening Bolivia’s
valuable monopoly, was arrested and thrown into prison. He refused to betray Charles
Ledger and, having been beaten and half-starved was eventually released. His son,
Santiago, tried to help Mamani recover but it was too late and Mamani died a broken
man. Charles Ledger received little reward for his part in this exploit and died a
pauper in Australia in 1905.
Ironically, it was the Dutch government who, while paying only a hundred guilders for
the seeds, ended up making one of the best investments in European history. Within a
short time the Dutch plantations of Java were producing 97% of the world’s supply of
quinine and soon had a virtual monopoly. Although the British in India established
cinchona plantations, these were of a lower quinine content than those in Java and by
the early 20th century, India was receiving most of its quinine from Java. [ADD MORE
AS CAPTION ON ROLE OF QUININE see below]
The global supplies of quinine were, however, cut off from the Allies when Germany
captured the quinine reserves in Holland and the Japanese occupied Java during the
Second World War in 1942, seizing the Dutch plantations along with over 90% of the
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world’s supply of quinine. New antimalarials were desperately needed and one of the
most successful outcomes of scientists’ endeavours to replace quinine was the
development of the synthetic drug, chloroquine, which was used widely after the
Second World War. In spite of a global initiative to eradicate malaria in the late 1950s
and 1960s (primarily using chloroquine as well as the insecticide DDT), malaria has
remained one of the leading causes of death, especially in sub-Saharan Africa. The most
recent antimalarial to come onto the market is derived from an ancient Chinese herb –
Artemisia annua – which was ‘re-discovered’ by the Chinese in the early 1970s and is
another fascinating story (INCLUDE SHORT VERSION OF BOX X). [ ADD>
Tragically, resistance to many of the antimalarial drugs has become a major problem in
the recent past – see also BOX on artemisia …ADD here … The search for ‘old’ and
‘new’ effective and affordable drugs to prevent or cure malaria is just one of a number
of strategies that are still desperately needed to control this debilitating and, often, fatal
disease.]
The examples of morphine, heroin, cocaine, aspirin and quinine were some of the
most important advances for medicine in the 19th century. Many drugs still in use
today are originally derived from plants, although most are now synthesized in
laboratories for commercial distribution. Modern treatments derived from plants
include the anti-leukaemia drug vincristine, found in the Madagascar periwinkle, and
the breast cancer agent taxol, first extracted from ancient Yew trees of Japan and the
Pacific Northwest. Effective remedies extracted from complex plants continue to
challenge scientists to explore other miracle cures lurking in the bushes. [Check link
to next Chapter … eg BOX 2].
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1. ‘The Peruvian bark, of which the Jesuites powder is made, is an Excellent
thing against all sorts of Agues’ (William Salmon, Synopsis medicinae, 1671)
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