Rubbing a dock leaf on a nettle sting works
In folk medicine, there is a widely held belief that following a nettle sting, a dock leaf rubbed on the affected part brings instant relief and a lasting cure. Some people even have rhymes to repeat while rubbing. Is the traditional folk cure an old wives tale or has it a basis in fact?
First, the stingy substances in nettles are mainly formic acid, as in an ant sting, and histamines, together with some other less important chemicals. Being an acid, it follows that the cure for treating a nettle sting has to be an alkaline substance to neutralise the acid. So, do dock leaves contain an alkaline substance or some natural, fast-acting antihistamine?
The answer is no; dock leaves do not contain any known alkaline substance or antihistamine. In fact, if anything, dock leaves are themselves slightly acid.
The answer appears to lie in the rubbing. Rubbing vigorously removes the offending nettle hairs and disperses the acid in the skin thereby lessening the pain of the nettle sting. Vigorous rubbing also bruises the dock leaf releasing moist sap giving both a soothing and a lubricating effect and an added cooling effect as the liquid evaporates.
And then there is the placebo effect. We all learned as children that rubbing a dock leaf on a nettle sting relieved the burning sensation. Everybody said it did, so it had to be true, so we went along with the centuries-old belief. And because we believed, it worked.
We now know that any soft, juicy leaf will do the trick. A dock leaf is, of course, a very good choice of juicy lea and it happens to work very well.
Docks are a small group of nine species. The two small members, Sheep’s Sorrel and Common Sorrel, both have spear-shaped leaves and a sour, acid taste. The other seven members of the group are larger.
Some plant names are self-explanatory: Curled Dock has curled, wavy leaves and Clustered Dock has clustered flowers. No prizes for guessing the explanations for the names Wood Dock and Broad-leaved Dock.
All of the aforementioned are either very frequent or abundant and can be troublesome weeds in pastures. The remaining trio are all rare or local. The Water Dock is most common around the River Shannon. The Fiddle Dock is a rare casual, and the Golden Dock with its lovely golden leaves is very rare. It is found in wet places near lakes and ponds and its population tends to fluctuate from year to year.