杏吧原创

A QUICK, daily rub with a stinging nettle can bring a warm tingle of relief
to aching joints, according to a British study on patients with osteoarthritis
of the thumb. The research gives credence to folk remedies for the treatment of
arthritis.

鈥淚t doesn鈥檛 hurt as much as you think,鈥� says Colin Randall, head of a project
at the Plymouth Postgraduate Medical School in Devon investigating the
phenomenon, 鈥渂ut it did have a significant effect.鈥� Randall, a retired family
doctor, decided to investigate after reading anecdotal reports about nettle
treatment. 鈥淚t was used by soldiers in Roman times, and recommended by John
Wesley, the 18th-century Methodist preacher,鈥� he says.

Randall and his colleagues recruited 27 patients with osteoarthritis of the
base of the thumb. All were on modern medications such as analgesics, and none
had ever tried nettles for pain relief.

鈥淲e got them to treat the painful area with the nettles for 30 seconds once a
day for a week,鈥� says Randall. Half the volunteers rubbed their thumbs with
leaves of a genuine stinging nettle (Urtica dioica), and half with
leaves from a white dead-nettle (Laminum album) which look identical
but don鈥檛 sting and are not considered helpful. The patients were not told to
expect beneficial effects with either.

Five weeks later, the 鈥渢reatments鈥� were swapped over, so each patient ended
up trying both nettles. The volunteers assessed their pain relief on a standard
scale from 鈥渘o pain鈥� to 鈥渨orst pain ever鈥�, and Randall established that the
stinging nettles had a statistically positive effect compared with the control
nettles. Relief was greatest when the sting caused a weal. 鈥淭hey tended to get a
very marked pricking for about 30 minutes after treatment, followed by a warm
tingling for around 24 hours,鈥� he says. After that, some experienced prolonged
anaesthesia where the nettle had been rubbed, so the subsequent treatments
sometimes didn鈥檛 hurt at all.

Seventeen of the patients were so pleased with the treatment that they
planned to use it again. Fourteen preferred it to their pre-existing
treatment.

Randall would like to investigate the effect further. He and his team
speculate that compounds in stinging nettles such as histamine or the
neurotransmitters serotonin and acetylcholine might relieve discomfort by
affecting pain receptors.

Apart from the rash normally caused by stinging nettles, the team found no
adverse effects. But Randall advises would-be users to treat them with care.
鈥淧eople who look at natural remedies think they鈥檙e ultrasafe, but this is not
necessarily true at all,鈥� he says.