Laxative drugs aloes

The related sennosides, glycosides A, B, C and D, occur in amounts of 1.5-3% in the leaves of Egyptian senna shrubs that are cultivated primarily in India. Senna leaves were previously used by Arab physicians as a laxative drug and digestive stimulant. Heterobianthrones sennosides A (meso-derivative, 9-169) and B (trans-derivative, 9-170) are bianthrone glycosides derived from aloe-emodin and rhein, homobianthrones sennosides C meso-derivative) and D (tra s-derivative) are derived only from rhein. 

The family, characteristic of Arabia and South Africa with some species in other parts of Africa and Madagascar, has been separated from the Liliaceac. Species have been introduced elsewhere. Several have been used as a source of laxative anthraquinones and as a component of cosmetic preparations. Aloe is one of the oldest drugs. 

The Food and Drug Administration (FDA) has mled that the stimulant laxatives aloe (including aloe extract and aloe flower extract) and cascara sagrada (including casanthranol, cascara fluidextract aromatic, cascara sagrada bark, cascara sagrada extract, and cascara sagrada fluid extract) in over-the-counter formulations are not safe and effective or are misbranded (9). 

The active purgative ingredient in the aloe is called barbaloin. The barbaloin is a prodrug and once in the colon is it converted to the active substance, aloe-emo-din an throne [22, 23]. The conversion to active drug is facilitated by the colonic flora. The laxative action results from the inhibition of colonic Na-K-ATPase with the resultant increase in the water content of the colon. 

Aloe is approved by the U.S. Food and Drug Administration as a laxative. ... 

Concomitant use of aloe latex is cautioned with antiarrhyth-mic drugs and botanicals containing cardiac glycosides, as long-term use of aloe latex as a laxative can cause potassium loss, leading to increased toxicity of these drugs and botanicals (Brinker 2001 De Smet 1993). 

Use of stimulant laxatives, such as aloe latex, may reduce the gastrointestinal transit time and thus reduce the absorption of orally administered drugs (Brinker 2001 De Smet 1993). 

Anthraquinone glycosides have long been used medicinally as cathartics and laxatives. Plant-derived drugs of this type include aloes Aloe species), cascara sagrada (Rhamnus purshiams), frangula (Rhamnus frangula), rhubarb (Rheum officinale), rumex or yellow dock (Rumex crispus) and senna (Cassia spp.). Many of the commercial preparations (patent medicines) based on these plants are readily available. 

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