History
Though it is a native of Himalayas, it was probably unknown to ancient Hindu physicians. But, it has found mention in later Sanskrit writing . The plant was well known to Greeks, Persians and Arabians. There were three kinds, white, black and red mentioned in Hyoscyamus of which white was the preferred variety. It was used as a household drug. Dioscorides has mentioned about drug in his literature. It is written about even in 'The
Arabian Nights' and in Anglo-Saxon work on medicine. Eastern writers refered to it as intoxicating, narcotic and an anodyne. It was applied to relieve pain related to inflammatory swellings. There was no mental excitement or sensory illusion associated with it except an overpowering tendency to sleep which come on and lasted for 11 hours when taken internally. The records show discrepancies arising from use of Hyoscyamine, the principal alkaloid of the plant, these were attributed to the use of impure or inert samples of the alkaloid.
Habitat
It is a high altitude plant found in Europe, west and north Asia. In India it is found from 5,000 to 12,000 ft. high in western Himalayas from Kashmir to Garhwal.
Morphology Description (Habit)
It is an erect, annual or biennial, hairy and viscid herb with bad odour. Stem robust and grows up to few meters in high. Radical leaves are smaller, sessile, ovate, pinnatifid and passing in to bracts. Flowers appear from August- September, lower ones are in the forks of the branches, upper solitary in the axis of the leaf like bract, forming insided spikes roller back at the top before flowering, which ultimately forming elongated and straight. Calyx is urn shaped, shortly 5 lobed, limb funnel shaped and in fruit it is elongated. Corolla funnel shaped lobes 5, short, slightly unequal, purple in base, limb lurid green, purple veined and darker in the centre. Stamens are protruding out. Ovary 2 celled. Capsule globose. Seeds are compressed, many and scrobuculate.
Principal Constituents
Hyoscyamine and hyoscine are the principal alkaloids other than cuscohygrine, apohyoscine and belladonnine. Total alkaloid percentage is 0.16% in roots, 0.045-0,08 in leaves and up to 0.1 % in flowering tops, but higher in tetraploid plants. In leaves the % depends on the altitude and the age of the leaf. Mature leaves are richer in hyoscyamine than hyoscine; tender leaves are relatively richer in hyoscine. In roots the alkaloid concentration is higher during the end of the vegetative period. The leaves yeild hyoscypikin in addition to hyoscyamine. Besides alkaloids, it contains volatile base similar to those present in belladonna leaf, a bitter glycoside hyoscypicrin, choline, mucilage and albumin. It is rich in potassium salts. On destructive distillation, the leaves yield a poisonous empyreumatic oil1. Traces of tropine and scopoline are also present. Atropine occurs only in the roots of biennial plants at the end of the vegetative period2.
Pharmacology
The therapeutic value of Hyoscyamus is comparable to that of belladonna, which also contains hyoscyamine. The action of Hyoscyamus however, is modified by the presence of a comparatively larger quantity of hyoscine, which produces a central narcotic effect3. If the scopolamine is administered i.p., protected guinea pig against bronchospasm produced by inhalation of histamine spray. It had antihistaminic activity equal to that of atropine but was almost inactive even at high dise against oedema of rat paw injected with kaolin suspension4. Scopolamine HBr had antihistaminic effects in guinea pig5.
Toxicity
The plant, especially the seeds, in large doses, produces poisonous effects similar to those of Datura poisoning, such as dryness of the tongue and mouth, giddiness and delirium. The plant if eaten by livestock affects the yields of milk and butter6.
Indications
Hyoscyamus has anodyne, narcotic and mydriatic properties. It is principally employed as a sedative in nervous affections and irritable conditions, such as asthma and whooping cough, and is substituted for opium in cases where the later is inadmissible. It is also used to counteract the griping action of purgatives and to relieve spasms in the urinary tract. In Veterinary practice, it is used as a urinary sedative. Hyoscyamus leaves have been employed externally to relieve pain, but their utility for this purpose is not well established. It has pungent, astringent, diuretic, alterative, antiperiodic and purgative properties. Plant is used in piles, skin eruptions, opthalmia, dysentry eye and liver complaints, rheumatism, scabies, bronchial affections and in leprosy. Leaves useful in gonorrhoea. Roots in cancer, stomach troubles and bladder stones. Seeds are useful in renal dropsy, bronchial affections and in leprosy. Branches and roots useful as tooth brushes. The seeds posses anodyne and narcotic properties but they have been rarely used in medicine. They are employed mainly for the extraction of alkaloids. Mixed with wine, they are applied to gouty enlargements and swellings. Powdered seeds and smoke from burning seeds are applied to relieve toothache. A suppository prepared from seeds is used in painful affections of the uterus. The seeds are also employed in poultices for eye troubles.
References
- Thorpe, VI, 203 ; Hocking, loc. cit. ; U.S.D., 1955, 674.
- Thorpe, VI, 203; Henry, 66; Hocking, loc. cit.; U.S.D., 1955, 675; Chem. Abstr, 1932, 26, 3621.
- U.S.D., 1955, 675; Allport, 34.
- Congr. Int. Therap., 6th, Strasbourg 1959, 443; Chem. Abst. 1962, 56, 12258f.
- Therapie 1960, 15, 326; Chem Abst. 1962, 57, 9176g.
- Modi, 641.
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