Effect of drugs on nutrient absorption
Simultaneous treatment with medicines and food can lead to malabsorption of essential nutrients, water- and fat-soluble vitamins, fat, Macro- and trace, electrolytes, etc.. Machinery violations of this process varied, but a manifestation of them can be direct, and indirectly, namely:
- damage mucosal epithelium of the small intestine with subsequent morphological changes therein;
- the effect on the nervous, endocrine and cardiac system (changes in the secretion, Education sosudov, the rate of blood circulation, Motor function of intestines, and cell membrane permeability of the vascular wall etc..);
- inhibition of digestive enzymes in the oral mucosa and gastrointestinal tract;
- chemical and physical (adsorption) drug interactions with food components;
- influence on the development of saprophytic flora, producing some vitamins and other physiologically active.
Malabsorption, and nutrient absorption is directly proportional to the dose and duration of medication. Hence the importance of respect for the individual takes medication regime, avoiding excess and single-dose course, compulsory treatment interruption. A classic example of malabsorption of nutrients in the body is a malabsorption, t. it is. malabsorption of fat in the intestines, carbohydrates, protein, vitamins, and drugs.
This disorder is most common during prolonged chemotherapy. Dysbacteriosis, caused by antibiotics, alter the intestinal microflora with increased growth Bacteroides, clostridia, pathogenic fungi, which decrease the activity of enzymes mucosa, involved in the absorption of food and drug substances.
Malabsorption of nutrients in the digestive tract under the influence of drugs | ||
The drugs | Called effect | Mechanisms of malabsorption |
| Aluminum hydroxide | Inhibition of food intake of phosphates, resulting in osteomalacia, dementia and anorexia. Inhibition of absorption of vitamin A, gland | Changes in physical and chemical properties of drugs and functions of the digestive tract. The formation of an insoluble complex with iron antacid |
| Biguanidы (synthetic oral hypoglycemic agents) | Glucose malabsorption, a-ксилозы, vitamin B12, amino acids and fats | Increased tissue effects of insulin, change in the rate of oxidative phosphorylation in the mitochondria |
| Calcium carbonate | Celiac disease | |
| Contraceptives | Violation of the absorption and assimilation of folic acid | |
| Mannitol | Glucose malabsorption; celiac disease | |
| Neomycin sulfate | Reducing the intake of carotene, fat, amino acids, gland, vitamin B12, α-glucose and xylose, cholesterol, Vitamin K, monosaxaridov | The direct toxic effects on the intestinal mucosa with the advent of clavate thickening of the villi, lymphocytic infiltration and plasmocytic, stretching microvilli. The amino groups of neomycin can bind and precipitate anions of fatty acids and bile |
| PAS | Celiac disease (11-17 g / day.), hypocholesterolemia, malabsorption of vitamin B12, folic acid, a-ксилозы, gland | Having the structural similarity between PAS and folic acid leads to a competitive inhibition mechanism of penetration of vitamin B12 through the intestinal epithelium into the blood |
| Anticonvulsants, barbiturates, neuroleptics | Malabsorption and utilization of folic acid, vitamin B12, a-ксилозы | |
| Cardiac glycosides | The decrease glucose absorption | Violation of transport through the intestinal wall |
| Laxatives | Reducing the intake of all nutrients, moderate steatorrhea (Fat Loss 9-15 g / day.), Loss of calcium ions, Potassium, inhibition of glucose uptake | Increased motor and secretory function of the intestines, incomplete digestion,accelerating the onset of bowel movements |
| Sulfonamides | Decreasing the synthesis of folic acid and vitamin K | Oppression saprophytic intestinal flora |
| Triamterene | Malabsorption of folate | |
| Chloramphenicol | Reduction of protein synthesis and amino acid transport inhibition | |
| Cholestyramine | Malabsorption of vitamin B12, a-ксилозы, carotene, electrolytes, gland, sugar, Vitamin K, bleeding, osteomalacia | Education nonabsorbable complex with bile acids, which are necessary for the metabolism of many nutrients |
| Xolinomimetiki | Diarrhea | Hyperperistalsis, body toning and strengthening intestinal secretion in the gastrointestinal tract |
| Cytostatics (folic acid antagonists) | Malabsorption of vitamin B12, a-ксилозы, carotene; celiac disease | The development of edema and infiltration villi cell round, inhibition of intrinsic factor (gastromukoproteina) |
Group laxatives (anthracene derivatives, Castor oil, izafenin, saline laxatives and others.) It reduces the absorption of nutrients by increasing motor and secretory functions of the intestine, incomplete digestion of food and accelerating defecation, violates the water-salt metabolism in the body. For the same reason, long-term use of diuretics contraindicated, that, Besides, may cause such lesions, how alkalosis, hypokalemia, protein malnutrition.
Mannitol, calcium carbonate and other drugs can deduce fat from the body by binding with fatty acids. Mannitol violates the absorption of glucose, water, salts, triamterene - folic acid. Nicotinic agents restrict the absorption of nutrients from food.
Antibiotics can disrupt the function of the digestive tract, change the frequency of stools, increase the amount of undigested food and thus influence the absorption of substances. So, Chloramphenicol inhibits the intestinal cells in the synthesis of proteins, necessary for foodstuffs, impairs their assimilation; neomycin reduces the absorption of carotene, amino acids, fat, gland, fat-soluble vitamins, B vitamins12 and K, glucose and D-xylose, electrolytes.
Anticonvulsant and anticancer drugs, barbiturates and neuroleptics, As folic acid antagonists, violate its absorption and utilization, and long-term use of vitamin D exchange violate; reduce the absorption of vitamin B12 and D-xylose, and chlorpromazine - violates the transport of amino acids. Anticholinergic agents, containing atropine, monosaccharides enhance absorption by increasing the time of contact with the mucosa of carbohydrates, due to a decrease in tone and motor function of the stomach and intestines.
Carbamazepine blocks the absorption of biotin (Vitamin H), which plays an important role in the growth and assimilation of fats, carbohydrates and proteins. Lack of this vitamin in the body leads to dangerous complications, including neurological disorders, and sometimes to death. Add levels of biotin in the body can be, eating liver, boiled eggs, greens.
