New Scientist – August 17, 2019

17 August 2019 | New Scientist | 21

As of 1 November last year,

doctors in the UK have been able

to prescribe medical cannabis. But

now they also face advice not to.

Draft guidance released last

week by the National Institute for

Health and Care Excellence states

that cannabis products shouldn’t

be offered to people with chronic

pain or muscle spasticity, unless

as part of a trial. It also says there

isn’t enough evidence that these

products work in severe epilepsy.

The guidelines, which are open

to comments, will come as a

disappointment to individuals who

are already struggling to get a

prescription for medical cannabis

products. The UK produces more

legal cannabis than any other

country, but medical cannabis

is still hard to come by. Some

National Health Service trusts

won’t pay for cannabis

prescriptions, so some people may

obtain them from private clinics.

The US landscape is even

messier. At the federal level,

cannabis that contains less than

0.3 per cent of the psychoactive

component tetrahydrocannabinol

(THC) is legal. Plants with higher

levels are not.

Still, whether or not you can

legally buy cannabis varies

from state to state. Some have

legalised medical cannabis;

others have approved the drug

for recreational use. Again, the

list of conditions that can be used

as a legitimate reason to buy

medical cannabis varies by state.

“When states passed laws,

those laws weren’t based on

evidence – they were passed

for political reasons,” says Ziva

Cooper at the UCLA Cannabis

Research Initiative in Los Angeles.

Medicinal cannabis

considered an alcoholic beverage.

“We don’t actually know what’s

in many of the products that are

being sold,” says Sumnall, as there

is no specific body checking CBD

products. “Because the CBD

market is not regulated properly,

we don’t really have any control

over quality or content,” he says.

Several factors can influence

how much CBD is in a product

extracted from a cannabis plant.

Levels can vary between batches

from the same grower. There are

only a couple of firms worldwide

that supply standardised products

certified for medical use.

Worse, CBD products could also

contain potentially harmful heavy

metals and pesticides. Cannabis

plants are especially good at

sucking these up from soil. Tests

of 240 CBD products in the US

suggested that 70 per cent were

contaminated with heavy metals,

as well as pesticides and toxic

mould, according to a report from

media outlet CBS Austin in May.

Other media investigations have

made similar findings, although

the retailers dispute the results.

Another worry is that those

who are unwell might be getting

medical advice and treatment

from people who aren’t qualified

to give it. “The vernacular term

in the US is the ‘budtender’,”

says Gidal. “Who knows what

educational background they have

and they are making important

medical decisions for you about

the dose and what preparation

you ought to be taking.”

I was tempted to try CBD to

see what all the fuss is about. But

with 10 CBD gummies costing £20,

the price alone was enough to put

me off. Given that I can’t be sure

what is in the products – let alone

their effects on my body and

brain – I have decided I would

rather not put my health in the

hands of the budtender. ❚

or whether taking it in the form

of a pill, spray or tea makes any

difference.

On top of that, it isn’t clear

how much CBD is in a product.

When the UK Centre for Medicinal

Cannabis, which represents the

industry, sent 30 shop-bought

CBD products for lab testing,

it found that one item – a

30 millilitre bottle selling

for £90 – contained no CBD

whatsoever. Almost half the

products had measurable levels of

THC, making them illegal. And one

had enough ethanol to be legally

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licensed for use in the UK.
As the drug has only been
around for two years, the long-
term effects are unknown, says
Barry Gidal at the University of
Wisconsin. “So far, nothing has
cropped up, but it’s a new drug,”
he says. “We’re going to have to
watch it for a while and be vigilant.”
From the drug trial, CBD
appears to be safe and isn’t
addictive, but the UK’s National
Health Service lists drowsiness,
diarrhoea, rashes and an increased
risk of infections as potential
side effects.
There is also a lack of evidence
on appropriate dosage, although
salespeople are often willing to
offer advice on how much of each
product to use.
“It’s all made-up stuff,” says
Gidal. No one knows how much
CBD will affect any one individual,

▲ Water bears

A giant leap for tiny

animals. It has been

revealed that tardigrades

may be loose on the moon

after a spacecraft carrying

them crashed in April.

▲ Bees

Who ya gonna call? Swarm

catchers! Apiarists are

having to step in to find

homes for Berlin-based

bees when hobbyists fail

to create a perfect hive.

▲ Solar

It’s a sun roof, just not as

you know it. Hyundai has

unveiled a car with solar

panels on its roof that will

help charge its batteries.

▼ Troublemakers

A Scottish football team

has a hooligan problem.

Due to food theft and

pitch invasions, gulls

are no longer welcome

at the club.

▼ CCTV

I’ll have two pints and a

privacy impact statement

please. Face recognition

tech will soon be deciding

whose turn it is to get

served in a London pub.

Working

hypothesis

Sorting the week’s

supernovae from

the absolute zeros

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70 %

of CBD products tested were

contaminated with heavy metals