Steve Ainsworth examines the medicinal potential of a mind-altering substance with a long history

There’s the Golden Triangle of south-east Asia and the Swat Valley in Afghanistan. And the mountains of Peru are equally famed for their output of agricultural products the possession of which in the UK is likely to invite more than casual interest from the local constabulary.

Indeed, anyone in Britain who sets up their own little farm to cultivate unusual crops is likely to find Mr Plod knocking on their front door at 6am – and nothing left of the door but matchwood by 6.01am.

But if you have a licence ...

Down in Wiltshire, or possibly Dorset, top-secret cannabis farms are rumoured to be springing up like ... well, like weeds.

Hello Mary Jane! In southern England, glasshouses bursting with marijuana plants are enjoying the full protection of the law, and providing the raw ingredients for Sativex, manufactured by GW Pharmaceuticals.

These days it’s a multi-million pound international business. GW was co-founded in 1998 by Dr Geoffrey Guy and Dr Brian Whittle, two well-known entrepreneurs in the UK biotech sector. Based at the rather ominously named Porton Down Science Park in Wiltshire, the company has cornered the market in developing a portfolio of cannabinoid medicines.

It is of course not new. Pharmacists have long tried to make use of cannabis as a medicine, and it was once included in dozens of proprietary products sold over- the-counter in the nineteenth century and in the early years of the 20th century. Amongst a plethora of ‘asthma cigarettes’, for example – once available from all good pharmacists – the French company Grimault & Sons was particularly notable for marketing its cannabis cigarettes.

First record

In 2,700 BC the first written record of cannabis use appeared in the pharmacopoeia of Shen Nung, one of the fathers of Chinese medicine.Two millenia later, the Persian prophet Zoroaster gave ‘hemp’ first place in the sacred text, the Zend-Avesta, which lists over 10,000 medicinal plants. It was, however, the Romans who bequeathed the word cannabis to the world – it’s simply Latin for hemp.

In Britain, Queen Elizabeth I decreed in 1563 that land owners with 60 acres or more must grow hemp or face a £5 fine. The Virgin Queen, however, had in mind the usefulness of hemp for manufacturing rope, rather than roll-ups, for the Royal Navy. Cannabis was, however, seemingly forgotten by pharmacists in the British Empire until 1841, when Dr W B O’Shaunghnessy, a Scotsman working in India, introduced, or perhaps reintroduced, cannabis to western medicine. In the following half century, hundreds of medical papers would be written on the medical benefits of ‘Indian Hemp’.

The Smith Brothers of Edinburgh began marketing a highly active extract of Cannabis indica in 1857. It was used as a basis for innumerable tinctures.One of Queen Victoria’s personal physicians, Sir Russell Reynolds, favoured prescribing cannabis for menstrual cramps. In 1890, he wrote in The Lancet that Cannabis indica, “when pure and administered carefully, is one of the most valuable medicines we possess”.

Five years later, in 1895, the Indian Hemp Drug Commission concluded that cannabis “has some medical uses, no addictive properties and a number of positive emotional and social benefits”. But not everyone agreed. The possibility of putting controls on the use of cannabis was raised at the first International Opium Conference held at the Hague in 1912.

One of Queen Victoria’s personal physicians favoured prescribing cannabis for menstrual cramps

A revised International Opium Convention was signed at Geneva on February 19, 1925. Implemented worldwide in 1928, as well as controlling the trade in opium, the treaty also banned the exportation of Indian hemp to countries that had prohibited its use, and required importing countries to issue certificates approving importation and stating that the shipment was required “exclusively for medical or scientific purposes”. It also required parties to “exercise an effective control of such a nature as to prevent the illicit international traffic in Indian hemp and especially in the resin”.

In Britain, the Dangerous Drugs Act became law in 1925, and cannabis was made illegal.

Attitudes, however, can change. In 1968, a Home Office select committee, chaired by Baroness Wootton, looked at the ‘cannabis question’. Its report concluded that cannabis was no more harmful than tobacco or alcohol, and recommended that the penalties for all marijuana offences be reduced.

Ban

Yet the 1971 Misuse of Drugs Act listed cannabis as a Class B drug, and even banned its medical use despite the recommendation of the Wootton Report that “preparations of cannabis and its derivatives should continue to be available on prescription for purposes of medical treatment and research”.

Times move on and, in 1993, Hempcore become the first British company to obtain a licence to grow cannabis as the Home Office lifted restrictions on industrial hemp cultivation. Almost at the same time, however, the then Home Secretary, Michael Howard, increased the maximum fine for possession from £500 to £2,500.

Meanwhile it’s often said that where the USA leads Britain soon follows. Today, across large swathes of the USA and Canada, cannabis is available on prescription. Perhaps it won’t be too long before Britain’s high street pharmacies are buying in stock from those secret sites in southern England!