Can be mistaken for : the garden variety called
Large-flowered Selfheal (Prunella grandiflora) but that has larger flowers and can easily be distinguished from Selfheal by the noticeable gap between the uppermost leaf-pair and the base of the flower-head (Selfheal has no gap between the base of the flower-head and the top-most leaf pair). Thus, none of the above specimens are
Large-flowered Selfheal, despite some of them having quite long flowering heads; the topmost leaf-pair is always just under the flowerhead (and the flowers are not large). The corolla, at maybe 20-30mm across and extending well beyond the radius encompassing the calyxes, is larger than that of the 10-15mm of Selfheal. Large-flowered Selfheal is introduced and naturalised, but only occurs as a short term relic. It inhabits banks or grassy places.
Hybridizes with :
Cut-leaved Selfheal (Prunella luciniata) to produce Prunella intermedia which differs in having toothed leaves and creamy-white flowers. At the very least, the uppermost leaf-pairs of
Cut-leaved Selfheal are deeply divided to about the mid-rib, the corolla is, at 15-17mm across, slightly larger than the 10-15mm of Selfheal and the flowers are creamy-white or white (only rarely pale-blue).
Some similarities to : Wild Thyme (when flower heads viewed hastily from above) but wild thyme has flowers that are much more mauve than the dark-blue of Selfheal.
Beware of several garden varieties, but these generally have larger flowers up to about twice the size.
It grows in grassy places such as lawns and woods, but also on the lower slopes of mountains.
Selfheal has been shown to have a variety of pharmacological effects including anti-inflammatory, anti-allergic, anti-oxidative, anti-microbial, anti-mutagenic and cytotoxic and has long been employed in traditional medicine.
Prunellin is a possibly unique, water-soluble anionic polysaccharide found in Selfheal with a molecular weight of over 10 kilo Daltons, and therefore it is not possible to show the chemical structure on these pages. It obtains its name from Selfheal (Prunella vulgaris) and exhibits anti-viral properties and also prevents the replication of HIV-1.
Selfheal also contains Rosemarinic Acid, a polyphenolic ester of Caffeic Acid and 3,4-diHydroxyphenol lactic acid. It inhibits several biological pathways including Interleukin 2, Leukotriene B4 biosynthesis, and some protein kinases. It is also an anti-oxidant, anti-viral, anti-bacterial, and anti-inflammatory, substances found not only in Selfheal, but in many other members of the Dead-Nettle [Mint] Family including Rosemary, Oregano, Sage, |
Thyme and Peppermint and others besides.