Question & Answer

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Anecdotally, several “treatments” are recommended for the relief of nettle stings. These include rubbing dock leaves (Rumex obtusifolius), sage (Salvia officinalis), peppermint (Mentha x piperita), mud, or even toothpaste on the site of the sting.
These treatments are based on the belief that nettle stings are caused only by a biochemical reaction, resulting in a painful, inflamed skin rash.
The evidence suggests that nettle stings are a combination of a biochemical reaction (from an acid touching the skin) and the mechanical action of tiny hair-like spikes called “trichomes” piercing human skin, therefore treatment may be more complex than previously thought.
It was believed that dock leaves have an alkaline pH, which could neutralise the acid in nettle stings, however we now know that the sap from dock leaves is also acidic.
It may be that dock leaves were historically used to treat nettle stings based on:
- their availability (they usually grow near nettles)
- when dock leaves are rubbed on to a nettle sting they might cause a placebo-based distraction from the pain of the sting (i.e. the person believes the intervention will help and this belief provides a beneficial effect).

Faulty logic “Old is better!” – Just because a treatment has been used for a long time or by many people, it does not mean that it helps or that it is safe.
Trust alone “It worked for me!” – If someone got better after using a treatment it does not necessarily mean that the treatment made them better. There are many other things to consider, even though they are rarely mentioned in casual conversations.
Just because using a treatment is associated with people getting better or worse, that doesn’t mean that the treatment made them better or worse.

Lead Researcher: Dr Sandra Galvin, HRB-Trials Methodology Research Network, NUI Galway.
Reviewed by: Elaine Finucane, HRB-Trials Methodology Research Network, School of nursing and Midwifery, NUI Galway.
Evidence Advisor: Prof Susan Smith, Royal College of Surgeons in Ireland and General Practitioner in Inchicore Family Doctors, Dublin.
Evidence Advisor: Casey Donaghey, PPI Ignite, NUI Galway.
Journalist Advisor: Dr Claire O’Connell, Contributor, The Irish Times.