Common
Evening Primrose (O. biennis) is the species most studied, especially as
a source of essential fatty acids. Most
or all of the species, however appear to have more or less the same medicinal
properties, though they are bound to vary somewhat between species in their
relative concentrations of various bioactive chemicals.
The
bark, leaves and root of the second year flowering plant are astringent,
sedative, relaxant and antispasmodic. They
are high in mucilage, making them useful in treating coughs and in soothing skin
irritations and eruptions. Additionally,
they are diuretic and may have sedative and pain relieving properties.
The
seeds (of O. biennis at least) are a source of easily assimilable
essential fatty acids (EFA’s), of which the body needs a constant supply. Many people have conditions that limit their ability to
metabolize and assimilate these EFA’s, a shortage of which then leads to all
sorts of subtle and not-so-subtle health problems. Supplements of Evening Primrose seeds or the oil extract have
been shown to be effective for treating heart disease, asthma, psoriasis,
premenstrual syndrome and a host of other problems (Terry Willard has an
excellent section on EFA’s and Evening Primrose in his Textbook of Advanced
Herbology).
O.
biennis seed
oil is also an excellent source of the pain relieving compound phenylalanine.
Dosage for the oil is 400-500 mg daily.
