Intestinal Bypass

JP Kampmann, H Klein, B Lumholtz, JEM Hansen. Ampicillin and propylthiouracil pharmacokinetics in intestinal bypass patients followed up to a year after operation. Clin Pharmacokinet 9 168-176, 1984. 

A two-hundred-pound teenager quit school because no desk would hold her. A three-hundred-pound chef who could no longer stand on his feet was fired. A three-hundred-fifty-pound truck driver broke furniture in his friends houses. All these people are now living healthier, happier, and thinner lives, thanks to the remarkable intestinal bypass surgery first developed in 1967. 

Copper deficiency is extremely rare, and there is no evidence that copper ever need be added to a normal diet. Even in chnical states associated with hypocupremia (sprue, celiac disease, and nephrotic syndrome), effects of copper deficiency usually are not demonstrable. Anemia due to copper deficiency has been described in individuals who have undergone intestinal bypass surgery, in those who are receiving parenteral nutrition, in malnourished infants, and in patients ingesting excessive amounts of zinc. While an inherited disorder affecting copper transport (Menkes disease) is associated with reduced activity of several copper-dependent enzymes, this disease is not associated with hematological abnormalities. 

Since intestinal mucosa, especially in ileum, appears to synthesize cholesterol at a high rate even in man and since this synthesis is increased by the absence of bile acids (223), it is to be expected that in patients with intestinal bypass mucosal cholesterol production is markedly increased in the bypassed portion of the gut and should contribute to serum cholesterol. Ileal or more extensive intestinal resections, on the other hand, prevent this increase in synthesis and should reduce serum cholesterol more effectively than the sole bypass does. However, animal experiments indicate that in monkeys prevention of dietary-induced hypercholesterolemia is less effective by ileal resection... 

Rubino F, Forgione A, Cummings D et al. (2006) The mechanism of diabetes control after intestinal bypass surgery reveals a role of the proximal intestine in the pathophysiology of type 2 diabetes. Ann Surg 244 742-749... 

Clinical stresses which interfere with vitamin metabohsm, can result in calcium deficiency leading to osteomalacia and osteoporosis (secondary vitamin D deficiency). These stresses include intestinal malabsorption (lack of bile salts) stomach bypass surgery obstmctive jaundice alcoholism Hver or kidney failure decreasing hydroxylation of vitamin to active forms inborn error of metabohsm and use of anticonverdiants that may lead to increased requirement. 

The e. posure route partly determines the distribution of the chemical in die body. Like tlie chemical benzene, a single chemical may follow multiple routes of e. posure. The liver, like the skin, acts as a filter. The liver is the primary dcto.xification site. To.xicants that arc absorbed into the lungs, skin, mouth, and esophagus may temporarily bypass the liver however, toxicants absorbed tluougli the stomach and intestines follow the blood s direct path to tlie liver. 

Parenteral Fluids. During the past ten years interest has been renewed in the total alimentation of the infant by vein (2). The motivation for this is the fact that neonates may suffer from some congenital malformation of the intestinal tract which would require surgical resection. If this is done, then one needs some outside way for alimentation, bypassing the intestine, until the intestine is able to heal and recover its normal function. This may take many weeks. A second source of motivation is the small premature infant weighing less than a kilogram, whose immature central nervous system and gastrointestinal tract make it difficult to establish nutrition by oral intake soon after birth. These also require total intravenous nutrition for a substantial period of time. 

Enteric-coated tablets or capsules of garlic are better absorbed since an active ingredient, allicin, is acid labile. The tablets or capsules bypass the stomach and release their contents in the alkaline medium of the small intestine [4],... 

At present, despite the advantages offered by the buccal delivery route, such as the bypass of intestinal and hepatic first-pass metabolism for systemic delivery, very few pharmaceutical products employ this route of administration. The reasons that contribute to this situation include (1) high costs associated with development, (2) lack of standardized tests to identify drug candidates suitability for this route, (3) the limited understanding of the impact of metabolism and/or transporters found in the oral cavity mucosa on buccal delivery, and (4) the relatively small number of reports describing the usefulness and safety of excipients/permeation enhancers in humans [82, 83], Therefore, the... 

II. Nutritargeting as a Way of Bypassing Absorption Barriers A. Digestion and intestinal absorption of fat-soluble 202... 

Cholesterol metabolism. Hydrogenated oil, administered orally to hamsters at a dose of 20% of diet for 4 weeks, induced hypercholesterolemia. Oil feeding had no effect on cholesterol synthesis but markedly inhibited cholesterol esterification in both the liver and the intestine. The diet-induced hypercholesterolemia was strongly correlated with an increase in acyl-CoA/cholesterol acyltransferase activity. The hypercholesterolemia increased aortic uptake of cholesterol and hence acyl-CoA/cholesterol acyltransferase activity " Coconut fat, administered orally to rabbits with partial ileal bypass, produced a significant increase of serum total cholesterol and phospholipids concentrations. The effect on semm lipids of the type of fat was similar in control and partial ileal bypass rabbits A Coconut—a main source of energy for two... 

For patients who are treated chronically with parenteral iron, it is important to monitor iron storage levels to avoid the serious toxicity associated with iron overload. Unlike oral iron therapy, which is subject to the regulatory mechanism provided by the intestinal uptake system, parenteral administration, which bypasses this regulatory system, can deliver more iron than can be safely stored. Iron stores can be estimated on the basis of serum concentrations of ferritin and the transferrin saturation, which is the ratio of the total serum iron concentration to the total iron-binding capacity ( ). 

Injecting Psilocybe mushroom juice intravenously is not common but it is reported. Most psilocybin users are seeking a natural experience and use of needles is not considered natural. Intravenous injection is the fastest means of getting psilocybin to the brain. In less than 16 seconds, the psilocybin is mixed with the blood, taken to the lungs, returned to the heart, and delivered to the brain. As the natural barriers and buffers of the stomach, small intestine, and liver are bypassed, the chances of overdose and adverse side effects such as coma, convulsions, and kidney failure, are greatly increased. It is even more rare for users to inject psilocybin powder, as this drug is difficult to obtain on the street. Supposed psilocybin powder bought on the street is almost always LSD, PCP, or both. 

Archeological evidence of psilocybin liquid via enemas dates back to A.D. 1 and some tribes still practice this method today. In ancient times, a hollow bone or tube was inserted deep into the rectum. Then an animal bladder filled with the psilocybin liquid was attached to the end of the tube. The liquid was then squirted deep into the rectum and lower intestine. Because so many natural barriers are bypassed by this method, the user is at great risk for overdose, serious side effects, or death. 

A piece of the intestine is attached to the pouch, causing food to literally bypass (skip) the rest of the stomach and other parts of the digestive system. This reduces the amount of calories and nutrients the body absorbs. 

Bypassing intestinal transmembrane transporters mainly by a paracellular absorption would avoid or limit exposure of the substrate to these efflux pumps. Improved paracellular uptake can be achieved by using fatty acids, calcium chelators such as EDTA, papain, bromelain, surfactants, chitosans, polyacrylic acid or thiolated polymers. 

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