One of the most useful actions of black horehound is in treating nausea, particularly arising from motion or travel sickness and from inner ear problems, where ginger might be considered. It is also a good match with ginger or mint.
The pungency and bitter flavour of black horehound indicate its benefits for digestion. It appears to increase the flow of bile and has a protective action on the liver. In southern Italy it was traditionally used in cases of malaria to treat the swollen spleen and liver that accompany the disease.
Black horehound’s antispasmodic effect works well for menstrual cramps, and for normalising menstruation generally. It is helpful for treating irregular periods, and lack of menstruation as well as heavy periods [see box].
Like white horehound, black horehound is excellent for coughs. It is an expectorant, helping clear mucus out of the lungs, and as an antispasmodic is useful for dry, tickly coughs and asthma. In the past it was used to treat bronchitis as well as consumption (tuberculosis of the lungs).
We have found that it calms nervous over-activity, releasing muscle tension and anxiety. It can be helpful in cases of insomnia if the leaf tea is taken before retiring to bed.
Black horehound also has tonic properties, and makes a reputable remedy for tiredness and debility, low energy and general weakness, especially if accompanied by a loss of appetite. Hool also used it as a diuretic in treating oedema, and for internal gravel.
An ancient use, going back two thousand years to Dioscorides, was to bruise the leaves with salt to dress and heal dog bites (but this is not where ‘hound’ came from!). He also advocated mixing the leaves with honey for cleansing infected wounds and ulcers.