Tag Archives: laudanum

The opium fields of England

A surprising picture appeared in the Guardian newspaper towards the end of June. It showed fields, near Blandford, Dorset in South West England, painted lilac with the flowers of the opium poppy. This controversial crop, associated in many people’s minds with war-torn countries like Afghanistan, is now being grown commercially in England to produce the medically-important pain killer morphine. But just how did opium poppies come to be grown across swathes of rural England?

Opium and the opium poppy

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Papaver somniferum as described in a 19th century German book (from Wikipedia, click on the picture for more details)


The opium poppy, or Papaver somniferum as it is more correctly called, is an imposing plant with fleshy grey-green leaves, showy pastel coloured flowers and impressive pepper pot seed heads. Standing up to a metre tall, the opium poppy brings architectural interest to the garden but it has a darker side. Within the seed head is a milky liquid containing a mixture of narcotic chemicals including morphine and codeine. If the unripe seed head is pierced, this latex seeps out and, left to dry, this is opium, prized for its extraordinary psychoactive powers.

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The unripe seed capsule of an opium poppy pierced to release the opium (from Wikipedia)


Humans have used opium for many thousands of years and the earliest written reference to the drug comes from the Middle East around 4000BC. The ancient Egyptian, Greek and Roman civilisations were also well acquainted with the properties of the drug using it enthusiastically. Although growth of Papaver somniferum is typically associated with warmer climates, the opium poppy has a history of cultivation in the UK. In the 18th and 19th centuries, many houses in the East Anglian Fens grew a stand of white opium poppies so that the dried seed capsules could be used to brew a tea containing small amounts of morphine. This infusion helped counter the aches and pains suffered by people living harsh lives in what was then, a remote, unhealthy part of the country. Use was not confined to the Fens as  the Dorset-writerThomas Hardy, in The Trumpet Major, refers to poppy heads and pain relief.

By the 19th century, imported opium was freely available in the UK and was used extensively at all levels of society. Opium was supplied in many forms including laudanum, a tincture of opium in wine, popularised by the Dorset-born physician Thomas Sydenham. The drug was taken to relieve pain, to induce sleep and to treat cough and diarrhoea. Its euphoriant properties were also prized and recreational use occurred with some problems of dependence. Encouraged by the drug’s popularity, attempts were made in the late 18th and early 19th centuries to grow opium poppies commercially in the UK but these were abandoned in favour of imported Turkish opium.

From opium to morphine

Morphine was isolated from opium in the 19th century and the powerful pain killing and euphoriant properties of the pure drug were quickly recognised. These come at a price as, compared to opium, morphine has potentially dangerous side effects and is highly addictive. By the 20th century, all non-medical use was banned but, to the present day, morphine is widely prescribed to relieve moderate and severe pain especially after major surgery. Diamorphine (heroin) is also used for pain relief in the UK but we hear more about its illicit use, the problems of addiction and the associated criminal activity. All morphine used clinically is still obtained from the opium poppy, extracted either from crude opium or from the dried seed heads.

The 21st century opium fields of England

Poppy heads by Jane V Adams
Opium poppies growing near Bere Regis in Dorset, UK showing the seed heads (by Jane V Adams)


By the end of the 20th century, the morphine used for medical purposes in the UK was extracted from opium poppies grown in Tasmania and Spain. It was tacitly assumed that the climate in the UK was unsuitable for their commercial cultivation. In 1999, however, John Manners, a seed merchant from Oxfordshire questioned this doctrine. He had seen striking pictures of purple opium poppies growing commercially in Poland, and decided to have a go at growing the plants in the UK. He set up some small trial plots and grew the poppies successfully in the southern part of the country. But did they produce morphine when grown in the UK? With the help of the Scottish pharmaceutical company, Macfarlan Smith (now a division of Johnson-Matthey), he showed that indeed they did. A full field trial the following year in Oxfordshire was also a success and, by 2002, 100 hectares of opium poppies were being grown commercially in the UK, each hectare yielding about 15 kg of morphine. More farmers were persuaded to grow the crop and nowadays, early summer sees about 2500 hectares of farmland blooming with the unselfconscious lilac flowers, mostly in the counties of Dorset, Hampshire, Lincolnshire and Oxfordshire.

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Opium poppies growing in Lincolnshire, UK (from Wikipedia)


Although they were initially uneasy about growing opium poppies, farmers now find it to be a lucrative break crop to prepare the land for growing cereals or oil seed rape the following season. Farmers contracted to Macfarlan Smith must prepare the seed bed and sow poppy seed supplied by the company which also advises on agronomy and pest control while the opium poppies are growing. The UK climate seems to suit the poppies well and after flowering they are left to dry before the seed capsule and about 5 cm of stem are harvested. The harvest is taken to a central processing facility where the poppy seeds in the capsule are separated leaving “poppy straw”. Poppy seeds contain little or no morphine and are sold for various culinary uses such as bread making. Poppy straw is processed in Macfarlan Smith’s Edinburgh factory where the morphine is isolated by solvent extraction and purification. About half of the UK requirement of medical morphine (~60 tons/year) is now made from poppies grown in the UK, including those grown in Dorset. So when you come across these beautiful lilac-painted fields next summer, think morphine, think pain relief, and think poppy extracts ending up in medicine cabinets in hospitals and pharmacies.

I should like to thank Marilyn Peddle (www.marilynjanephotography.co.uk) for generously providing the featured image which is of opium poppies growing in North Dorset
and Jane Adams (https://urbanextension.wordpress.com/) for generously providing the photograph of opium poppies growing near Dorchester.

This is a slightly  modified version of an article that appeared in the September edition of the Marshwood Vale Magazine.

Poppy head tea, laudanum and heroin: now we can “see” where they act

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In the 19th century many houses in the Fenlands of East Anglia in the UK reserved a corner of their garden for a patch of white poppies.  The plants were harvested and dried to make “poppy head tea”, a beverage containing small amounts of morphine leached from the poppies.  The tea was consumed to counter the aches, chills, agues and fevers experienced in this bleak part of the UK.  The compounds present in the poppy heads may be obtained in a more concentrated form by piercing the unripe seed head.  A milky liquid seeps out and this is dried to produce “opium” which contains up to 10 % morphine.   Opium was consumed liberally in the 19th century in the form of laudanum.  This was a concoction of opium and alcohol, and was taken for relief of pain and to reduce cough.  Laudanum contains about 1% morphine and cases of addiction were common but the preparation offered the only source of pain relief for many.  Nowadays the highly addictive morphine derivative, heroin, is considered one of the most harmful drugs available. 

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There is an urgent need to find out more about how these drugs act and new research, published in Nature last week, shows for the first time a picture of the site of action of morphine.  This is a step change in our understanding of how these drugs work and a major advance in pharmacology.

The effects of opium have been known for centuries; some of the earliest reports date back to the ancient Greeks.  Morphine is the principal “opiate” in opium and quite how the drug worked was unclear until the 1970s when morphine was shown to bind to specific sites in the brain.  It seemed odd at the time that the brain should have binding sites for a plant-derived chemical but this conundrum was soon solved when natural opiates (enkephalins and endorphins) were discovered.  The sites where morphine bound opportunistically were in fact sites where the natural opiates acted to modulate brain function. 

These sites in our brains where morphine and the natural opiates bind and affect brain function came to be called opiate receptors.  Surprisingly, the principle whereby opiates are detected by their receptors is similar to that also shown for many other signals that humans are able to detect.  Other examples are smells, tastes, vision and the myriad chemicals (neurotransmitters) in the brain and hormones in other parts of the body that influence our behaviour.  The surprising conclusion of years of work in many labs has been that signal detection in all of these examples is based on a common principle.  In each case, there is a signal and a detector protein, termed a receptor, with the ability to recognise that specific signal and react to it.  The receptor collaborates with a transducer termed a G protein (named for its ability to bind a molecule abbreviated as GTP).  The receptor and G protein together sit in the membrane of a cell providing a signalling machine.  The signal molecule from the outside of the cell attaches to the receptor and activates the G protein sending a chemical stimulus to the inside of the cell and altering its activity.

Not only do we find this common principle of signal/receptor/G protein for many signalling systems but the receptors are also the sites of action of a third or more of currently prescribed drugs including many best sellers.  For example, drugs used to treat high blood pressure, asthma, schizophrenia and Parkinson’s disease act via these kinds of receptors.   Some illegal drugs such as cannabis and, of course, morphine also target this class of receptor.   If you are still not convinced of the importance of these receptors then bear in mind that if you are drinking coffee or tea while reading this, the caffeine in these drinks is also acting via one of these receptors.

In the new work, two labs in California (Brian Kobilka at Stanford and Ray Stevens at the Scripps Institute in La Jolla), have determined the structure of opiate receptors in three dimensions using x-ray crystallography.  Many labs had spent years trying to analyse the structures of this class of receptor until about five years ago a technical breakthrough made it possible to make crystals of the proteins.  The structures of several of these receptors have now been reported (see a previous post) and the new work describes the structures of two opiate receptors.     The images contained in these new studies show the structures of the receptor together with a drug sitting in its binding site.

Just having the structure of these opiate receptors is an important milestone in the field but they also open the way to rational drug design.  It should now become possible to design new drugs based on their ability to fit in to the binding site of these receptors.  The hope is that drugs will emerge that retain the pain killing ability of opiates but lack the addictive potential.

There is another fascinating aspect of one of the new opiate receptor structures:  the receptors were found in closely linked pairs.    There has been much circumstantial evidence that these kinds of receptors functioned as pairs, rather like identical twins, but this is some of the first hard evidence of this.

Se a related post: Shedding new light on how adrenaline works