Laxative drugs senna

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 two most important diphenylmethanes are phenolphthalein and bisacodyl. Senna and cascara are the sources of anthraquinone laxatives. However, although still available in some countries phenolphthalein is now removed from most markets because of concerns over carcinogenicity. As recent as 2006 the United States Food and Drug Administration (FDA) has categorized castor oil as generally recognized as safe and effective (GRASE) for over-the-counter use as a laxative. On the other hand, in 2002 cascara was banned by the FDA. 

Incompatibilities of metoclopramide depend on drug concentration, pH, and temperature. It is incompatible with cephalosporins, chloramphenicol, sodium bicarbonate, doxorubicin, cisplatin, and cyclophosphamide. Caution should be exercised with simultaneous administration of metoclopramide with lithium, sym-pathomimetics, antidepressants, bromocriptine, and carbamazepine. Omperazole interacts with tolbutamide, clarithromycin, and phenytoin. Coadministration of rantidine and cisapride increases the plasma concentration of rantidine. Abuse of senna laxative has been reported and may cause hepatitis.176-178... 

Apart from basic information such as name of drug, its purpose (laxative) and the dose and frequency it should be taken, it is important to impress on Mrs CR the necessity to not increase the dose beyond that prescribed unless recommended by her GP or hospital doctor. Unless she was to develop diarrhoea (which is possible while on chemotherapy treatment), she should be counselled to continue taking senna while on morphine treatment. 

Several studies have been conducted in order to establish and better understand the mode of action of anthranoid laxatives. For example, Lemli [14] presented a review of the study of the mode of action of sennosides, Fig. (1) the active constituents of the senna drug. An interaction between rhein-anthrone, the active metabolite of sennosides, and the immune cells of the colon is suggested as a base for laxative activity. Several studies aimed to... 

Use of stimulant laxatives, such as senna or sickle-pod senna, may reduce the gastrointestinal transit time and thus reduce the absorption of orally administered drugs (Brinker 2001 De Smet 1993). 

Concomitant use of senna or sickle-pod senna is cautioned with antiarrhythmic drugs, thiazide diuretics, corticosteroids, licorice, and botanicals containing cardiac glycosides, as long-term use of senna or sickle-pod senna as a laxative can cause or exacerbate potassium loss (Brinker 2001 De Smet 1993 ESCOP 2003). 

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. 

Smith WA, Taintor AR, Kos L, Drolet B. Senna-containing laxative inducing blistering dermatitis in toddlers. Arch Dermatol 2012 148 402-4. Ishikawa A, Sugiura K, Sato A, Muro Y, Akiyama M. Drug eruption due to sodium picosulfate. Eur J Dermatol 2012 22 410-1. 

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