Digitalis

Digitalis (pron.: /ˌdɪdʒɨˈteɪlɨs/[2] or /ˌdɪdʒɨˈtælɨs/[3]) is a genus of about 20 species of herbaceous perennials, shrubs, and biennials commonly called foxgloves. This genus was traditionally placed in the figwort family Scrophulariaceae, but recent phylogenetic research has placed it in the much enlarged family Plantaginaceae.[1] This genus is native to western and southwestern Europe,[4] western and central Asia, Australasia and northwestern Africa. The scientific name means “finger-like” and refers to the ease with which a flower of Digitalis purpurea can be fitted over a human fingertip. The flowers are produced on a tall spike, are tubular, and vary in colour with species, from purple to pink, white, and yellow. The best-known species is the common foxglove, Digitalis purpurea. This biennial plant is often grown as an ornamental plant due to its vivid flowers which range in colour from various purple tints through various shades of light gray, and to purely white. The flowers can also possess various marks and spottings.
The first year of growth of the common foxglove produces only the stem with its long, basal leaves. During the second year of the plant’s life, a long, leafy stem from 50 to 255 centimeters tall grows atop the roots of healthy plants.
The larvae of the insect the “foxglove pug” consume the flowers of the common foxglove for food. Other species of Lepidoptera eat the leaves, including lesser yellow underwing.
The term digitalis is also used for drug preparations that contain cardiac glycosides, particularly one called digoxin, extracted from various plants of this genus.
digitalis

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Anti-Histamines

AntihistaminesA histamine antagonist (commonly called an antihistamine) is a pharmaceutical drug that inhibits the action of histamine by blocking it from attaching to histamine receptors; or it may inhibit the enzymatic activity of histidine decarboxylase, catalyzing the transformation of histidine into histamine (atypical antihistaminics).
Antihistamines are commonly used for the relief of allergies caused by intolerance of proteins.[1]

Clinical effects

Histamines produce increased vascular permeability, causing fluid to escape from capillaries into tissues, which leads to the classic symptoms of an allergic reaction — a runny nose and watery eyes. Histamine also promotes angiogenesis.
Antihistamines suppress the histamine-induced wheal response (swelling) and flare response (vasodilation) by blocking the binding of histamine to its receptors on nerves, vascular smooth muscle, glandular cells, endothelium, and mast cells. They exert a competitive antagonism to histamines.
Itching and sneezing are suppressed by antihistamine blocking of H1-receptors on nasal sensory nerves.[2] Antihistamines have also been used with great success in the treatment of Brown Recluse (genus Loxosceles) spider bites as well as other insect bites that cause necrosis[3].