Belladonna Alkaloids: Alkaloids obtained from various plants, especially the deadly nightshade (Atropa belladonna), variety acuminata; atropine, hyoscyamine and scopolamine are classical, specific antimuscarinic agents with many pharmacologic actions; used mainly as antispasmodics.Atropa belladonna: A plant species of the genus ATROPA, family SOLANACEAE that contains ATROPINE; SCOPOLAMINE; BELLADONNA ALKALOIDS and other SOLANACEOUS ALKALOIDS. Some species in this genus are called deadly nightshade which is also a common name for SOLANUM.Solanaceous Alkaloids: Alkaloids, mainly tropanes, elaborated by plants of the family Solanaceae, including Atropa, Hyoscyamus, Mandragora, Nicotiana, Solanum, etc. Some act as cholinergic antagonists; most are very toxic; many are used medicinally.Atropa: A plant genus of the family SOLANACEAE which contain SOLANACEOUS ALKALOIDS including ATROPINE which is named after this genus.Alkaloids: Organic nitrogenous bases. Many alkaloids of medical importance occur in the animal and vegetable kingdoms, and some have been synthesized. (Grant & Hackh's Chemical Dictionary, 5th ed)Materia Medica: Materials or substances used in the composition of traditional medical remedies. The use of this term in MeSH was formerly restricted to historical articles or those concerned with traditional medicine, but it can also refer to homeopathic remedies. Nosodes are specific types of homeopathic remedies prepared from causal agents or disease products.Delphinium: A plant genus of the family RANUNCULACEAE. Members contain ACONITINE and other diterpenoid alkaloids.Hyoscyamus: A plant genus of the family SOLANACEAE which contains TROPANES.Scopolamine Hydrobromide: An alkaloid from SOLANACEAE, especially DATURA and SCOPOLIA. Scopolamine and its quaternary derivatives act as antimuscarinics like ATROPINE, but may have more central nervous system effects. Among the many uses are as an anesthetic premedication, in URINARY INCONTINENCE, in MOTION SICKNESS, as an antispasmodic, and as a mydriatic and cycloplegic.Ergot Alkaloids: Alkaloids originally isolated from the ergot fungus Claviceps purpurea (Hypocreaceae). They include compounds that are structurally related to ergoline (ERGOLINES) and ergotamine (ERGOTAMINES). Many of the ergot alkaloids act as alpha-adrenergic antagonists.Indole Alkaloids: Group of alkaloids containing a benzylpyrrole group (derived from TRYPTOPHAN)Pyrrolizidine Alkaloids: A group of ALKALOIDS, characterized by a nitrogen-containing necine, occurring mainly in plants of the BORAGINACEAE; COMPOSITAE; and LEGUMINOSAE plant families. They can be activated in the liver by hydrolysis of the ester and desaturation of the necine base to reactive electrophilic pyrrolic CYTOTOXINS.Vinca Alkaloids: A group of indole-indoline dimers which are ALKALOIDS obtained from the VINCA genus of plants. They inhibit polymerization of TUBULIN into MICROTUBULES thus blocking spindle formation and arresting cells in METAPHASE. They are some of the most useful ANTINEOPLASTIC AGENTS.Atropine: An alkaloid, originally from Atropa belladonna, but found in other plants, mainly SOLANACEAE. Hyoscyamine is the 3(S)-endo isomer of atropine.Cinchona Alkaloids: Alkaloids extracted from various species of Cinchona.