Plantain

These green, weedy plants are native to Europe and Asia, but now grow practically anywhere in the world where there is sufficient water. Plantain should not be confused with the banana-like vegetable of the same name. The leaves of plantain are primarily used as medicine. The seeds of plantain can also be used medicinally, having mild laxative effects similar to the seeds of psyllium, a close relative of plantain.

Plantain has long been considered by herbalists to be a useful remedy for cough, wounds, inflamed skin or dermatitis, and insect bites.¹ Bruised or crushed leaves have been applied topically to treat insect bites and stings, eczema, and small wounds or cuts. It was considered by herbalists to be a gentle, soothing expectorant, and additionally to have a mild astringent effect said to help remedy hemorrhoids or bladder infections with mild amounts of blood in the urine.²

The major constituents in plantain are mucilage, iridoid glycosides (particularly aucubin), and tannins. Together these constituents are thought to give plantain mild anti-inflammatory, antimicrobial, antihemorrhagic, and expectorant actions.^{3, 4} Plantain is approved by the German Commission E for internal use to ease coughs and mucous membrane irritation associated with upper respiratory tract infections as well as topical use for skin inflammations.⁵ Two Bulgarian clinical trials have suggested that plantain may be effective in the treatment of chronic bronchitis.^{6, 7} Insufficient details were provided in these reports to determine the quality of the trials or their findings. Although plantain was thought to possess diuretic properties, one double-blind trial failed to show any diuretic effect for this plant.⁸ A preliminary trial found that topical use of a plantain ointment (10% ground plantain in a base of petroleum jelly) was helpful as part of the treatment of people with impetigo and ecthyma, two inflammatory skin disorders.⁹ Insufficient details were provided in this report, however, to determine the quality of the study or its findings.

The German Commission E recommends using 1/4–1/2 teaspoon (1–3 grams) of the leaf daily in the form of tea made by steeping the herb in 1 cup (250 ml) of hot water for 10–15 minutes (making three cups (750 ml ) per day).¹⁰ The fresh leaves can be applied directly three or four times per day to minor injuries, dermatitis, and insect stings.¹¹ Syrups or tinctures, approximately 1/2 teaspoon (2–3 ml) three times per day, can also be used, particularly to treat a cough.¹² Finally, 1/2–1 1/4 teaspoons (2–6 grams) of the fresh plant can be juiced and taken in three evenly divided oral administrations throughout the day.¹³

Plantain is not associated with any common side effects and is thought to be safe for children.¹⁴ There is no information available about its use by pregnant or nursing women, though topical application appears to be safe. Adulteration of plantain with digitalis leading to dangerous side effects has been reported in Switzerland and the United States.¹⁵ Although rare, it points to the need for consumers to purchase herbs from companies that carefully test their herbal products for adulteration.