Peristalsis, colonic

Increases colonic peristalsis and enhances fluid and electrolyte secretion into the bowel... 

Phenolphthalein, like anthraquinones and other irritant phenolic compounds, is a stimulant laxative Colonic peristalsis is increased by stimulation of sensory nerve endings in the mucosa of the intestine. Phenolphthalein also enhances entrance of water and salts into the bowel... 

There are two different mechanisms behind ordinary causes of constipation, functional and outlet obstructions. Functional constipation is caused by the slower movement of the colon, peristalsis, which comes with old age, often in combination with less physical activity and less intake of fibre containing food. Outlet obstruction is a result of incapacity to empty the rectum from faeces often due to too large masses of stool blocking the anus. It can also be caused by anal stricture from haemorrhoids or scar tissue caused by fissures. 

Osmotic effect retains fluid in the colon, lowering the pH and increasing colonic peristalsis... 

Among newly developed colon-specific drug delivery systems, pressure-controlled delivery capsules (PCDCs) [161] can be mentioned. Their mechanism of action is based on the relatively strong peristaltic waves taking place in the colon and leading to an increased luminal pressure. They consist of a capsular-shaped suppositories coated with a water-insoluble polymer (ethyl cellulose). Once taken orally, PCDCs behave like an ethyl cellulose balloon, because the suppository base liquefies at body temperature. In the upper GI tract, PCDCs are not directly subjected to the luminal pressures since sufficient fluid is present in the stomach and small intestine. The reabsorption of water in the colon provokes an increase of the luminal content viscosity. As a result, increased intestinal pressures directly affect the system via colonic peristalsis. Consequently, PCDCs mpture and drug release in the colon take place. 

Hyperosmotic Lactulose Glycerin Glycerin suppository/ lactulose enema 0.25-1 Lactulose oral 24-48 Osmotic effect retains fluid in the colon and increases colonic peristalsis. Use when not responsive to stool softeners or stimulants. Titrate to number of stools per day. 

Concurrent colonization by Gram-negative bacilli occurs in some patients with failure of the gastric acid barrier, suggesting additional deficiencies of host defense abnormal oral flora, malnutrition, general illness, or diseases or medication interfering with intestinal peristalsis and clearance. This type of microflora is also seen in 10-30% of patients on acid inhibitors, for which mucosal injury and functional changes related to peptic ulcer and reflux disease may be responsible. 

When intestinal peristalsis and clearance are intact, the bacteria are rapidly transported aborally, and in the mid jejunum bacterial counts are in general low (normal) despite dense gastric colonization. Considerable evidence indicates that bacteria recovered from small bowel under such conditions are transient rather than resident. 

Roily and Liebermeister [95] showed that bacteria introduced into the small bowel disappeared rapidly, without bile, pancreatic, and intestinal juices having antibacterial properties alone or mixed. Later studies, of which those by Dack and Petran [96], Dixon [99] and Dixon and Paulley [100] are of particular importance, provided considerable further evidence that intestinal peristalsis is the main line of defense against bacterial colonization of the small bowel. This was also concluded by Donaldson [101-103] when he reviewed host defense mechanisms in 1964. At that time, however, the insights into small bowel motility were confined to the reflex-mediated peristaltic behavior. 

Pharmacological suppression of intestinal peristalsis in experimental animals leads to bacterial colonization of... 

Recently, an approach mimicking the GI tract and feasible for pharmaceutical dissolution studies has been published [47], Coming from the area of nutritional research, this approach reflects some promising aspects, such as relevant luminal pH values, peristalsis, luminal bacterial colonization, and relevant fluid volumes. However, permeation is only reflected by diffusion through hollow fiber membranes and thus is not in the scope of this chapter. Nevertheless, it will be interesting to see whether it will be possible to expand such a perfect in vitro device toward a more realistic intestinal epithelium. 

Fiuid and eiectroiyte baiance The use of this drug does not preclude the administration of appropriate fluid and electrolyte therapy. Dehydration, particularly in children, may further influence the variability of response and may predispose to delayed difenoxin intoxication. Drug-induced inhibition of peristalsis may result in fluid retention in the colon, and this may further aggravate dehydration and electrolyte imbalance. 

Colic. Pertaining to the colon acute abdominal pain characteristically, intermittent visceral pain with fluctuations corresponding to smooth muscle peristalsis. Conjunctivitis. Inflammation of the delicate membrane that lines the eyelids and covers the exposed surface of the sclera (conjunctiva), generally consisting of conjunctival hyperemia associated with a discharge. 

Mechanism of Action A GI stimulant that has a direct effect on colonic smooth musculature by stimulating the intramural nerve plexus. Therapeutic Effect Promotes fluid and ion accumulation in the colon, increasing peristalsis and producing a laxative effect. 

Mechanism of Action A lactose derivative that retains ammonia in colon and decreases serum ammonia concentration, producing osmotic effect. Therapeutic Effect Promotes increased peristalsis and bowel evacuation, which expels ammonia from the colon. 

It is stimulant laxative, when administered orally or as a rectal suppository it produces increased peristalsis by direct action on the mucosa of the colon, usually resulting in a soft, formed stool. 

It is an anthraquinone laxative. It is not active as such but after oral intake when it reaches colon the bacteria liberate anthrones, which is the active form. Active form acts on myenteric plexus to increase peristalsis. It also inhibits salt and water absorption in colon. 

Bulk-forming laxatives are indigestible, hydrophilic colloids that absorb water, forming a bulky, emollient gel that distends the colon and promotes peristalsis. Common preparations include natural plant products (psyllium, methylcellulose) and synthetic fibers (polycarbophil). Bacterial digestion of plant fibers within the colon may lead to increased bloating and flatus. 

Alee Vera (Aloe barbadensis) Uses Topically for bums, skin irritation, sunburn, wounds internally used for constipation, amenorrhea, asthma, colds Actions Multiple chemical components aloinosides inhibit H20 electrolyte reabsorption irritates colon which T peristalsis propulsion wound healing d/t i production of thromboxane A2, inhibiting bradykinin, histamine Available forms Apply gel topically 3-5/d PRN caps 100-200 mg PO hs Contra Do not use if PRG, lactating, or children <12 y Notes/SE Abd cramping, D, edema, hematuria, hypokalemia, muscle weakness, dermatitis Interactions w/ internal use T K+ loss W/ BB, corticosteroids, diuretics, licorice T effects OF antiarrhythmics, corticosteroids, digoxin, diuretics, hyperglycemias, jimsonweed EMS Assess for dehydration, electrolyte imbalance (hypokalemia), abd distress w/ internal use stimulates uterine contractions may cause spontaneous abortion... 

Black pepper oil can be used to help in the treatment of pain relief, rheumatism, chills, flu, colds, exhaustion, muscular aches, physical and emotional coldness, fevers, as a nerve tonic and to increase circulation. Furthermore, it increases the flow of saliva, stimulates appetite, encourages peristalsis, tones the colon muscles and is a general digestive tonic (Pruthi, 1993). 

Castor oil is broken down in the small intestine to ricinoleic acid, which is very irritating to the gut and promptly increases peristalsis. Cascara, senna, and aloe contain emodin which stimulates colonic activity. Onset of activity is delayed 6 to 8 hr because emodin is excreted into the colon after these agents are absorbed. Emodin may pass into breast milk. Phenolphthalein and bisacodyl are also potent stimulants of the colon. Adverse effects include abdominal cramps and the potential for atonic colon with prolonged use. 

In the colon, semifluid material entering from the small bowel is thickened by absorption of water and salts (from about 1000 ml to 150 ml per day). If, owing to the action of an irritant purgative, the colon empties prematurely, an enteral loss of NaCl, KC1 and water will be incurred. In order to forestall depletion of NaCl and water, the body responds with an increased release of aldosterone (p.168), which stimulates their reabsorption in the kidney. However, the action of aldosterone is associated with increased renal excretion of KC1. The enteral and renal K losses add up to K+ depletion of the body, evidenced by a fall in serum K concentration (hypokalemia). This condition is accompanied by a reduction in intestinal peristalsis (bowel atonia). The affected individual infers constipation and again partakes of the purgative, and the vicious circle is closed. 

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