Aminoglycosides absorption

ABSORPTION, DISTRIBUTION, DOSING, AND ELIMINATION OF THE AMINOGLYCOSIDES ABSORPTION... 

Hypomagnesemia is usually associated with disorders of the intestinal tract or kidneys. Drugs (e.g., aminoglycosides, amphotericin B, cyclosporine, diuretics, digitalis, cisplatin) or conditions that interfere with intestinal absorption or increase renal excretion of magnesium can cause hypomagnesemia. 

Absorption of antimicrobial agents, influencing factors, 15 Acidophilin, food preservative, 94,95t Agglutination application, 150 description, 149-150 American foulbrood control oxytetracycline, 36-45 sulfathiazole, 36,37f Amikacin, use in food animals, 19 Aminoglycoside detection, by... 

WARNING Systemic absorption of oral route may cause neuro/oto/nephrotox may result resp paralysis possible w/ any route of administration Uses Hepatic coma, bowel prq) Action Aminoglycoside, poorly absorbed PO -1- GI bacterial flora Dose Adults. 3-12 g/24- h PO in 3-4 doses Peds. 50-1 (X) mg/kg/24 h PO in 3-4 doses Caution [C, /-] Renal failure, neuromuscular disorders, hearing impair Contra Intestinal obst Disp Tabs, PO soln SE Hearing loss w/ long-term use rash, NA EMS Use neuromuscular blockers w/ caution, reduced dose may be necessary t bleeding risk w/ concurrent anticoagulant use OD May cause neuromuscular block and kidney failure calcium salts can be used to revise neuromuscular block... 

The pharmacokinetic behavior of the aminoglycosides is characterized by poor oral absorption. 

Kanamycin is an aminoglycoside complex produced by Streptomyces ka-namyceticus. It is comprised of three components, kanamycin A being the major component and kanamycins B and C minor congeners. Kanamycin is active against many pathogenic bacteria and has been used parenterally for treatment of bovine respiratory disease, mastitis, and other infectious conditions. A popular combination used in horses and cattle with respiratory disease is kanamycin and penicillin G. It is also used orally for treatment of bacterial enteritis because limited absorption occurs after oral administration. 

Administration The highly polar, polycationic structure of the aminoglycosides prevents adequate absorption after oral administration. Therefore, all aminoglycosides (except neomycin [nee oh MYE sin]) must be given parenterally to achieve adequate serum levels. [Note The severe nephrotoxicity associated with neomycin precludes parenteral administration, and its current use is limited to topical application or oral treatment in hepatic coma to reduce the intestinal bacterial population.]... 

Alendronate absorption is reduced by antacids, calcium salts and iron. Concurrent use with aminoglycosides may lead to hypocalcaemia. Patients should be told to take alendronate 30 minutes before food and other medication. 

METHOTREXATE -ORAL NEOMYCIN 1 plasma concentrations following oral methotrexate Oral aminoglycosides 1 absorption of oral methotrexate by 30-50% Separate doses of each drug by at least 2-4 hours... 

A similar situation arises in the case of the aminoglycoside antibiotics framycetin sulphate, kanamycin sulphate and acid sulphate, gentamicin sulphate, and tobramycin. Their infra-red spectra are dominated by hydroxyl and amino absorptions of the amino sugar and, except for tobramycin, by sulphate absorptions. The proton spectra however contain sufficient differences to distinguish them. 

Pharmacokinetics. Aminoglycosides are water-soluble and do not readily cross cell membranes. Poor absorption from the intestine necessitates their administration i.v. or i.m. for systemic use and they distribute mainly to the extracellular fluid transfer into the cerebrospinal fluid is poor even when the meninges are inflamed. Their t) is 2-5 h. 

Bums. Infection may be reduced by application of silver sulphadiazine cream. Substantial absorption can occur from any raw surface and use of aminoglycoside, e.g. neomycin, preparations can cause ototoxicity. 

Unowsky, J. Behl, C.R. Beskid, G. Sattler, J. Halpem, J. Cleeland, R. Effect of medium chain glycerides on enteral and rectal absorption of beta-lactam and aminoglycoside antibiotics. Chemotherapy 1988, 34, 272-276. 

The results of an in vitro study on immortalized mouse distal convoluted tubule cells have suggested that aminoglycosides act through an extracellular polyvalent cation-sensing receptor and that they inhibit hormone-stimulated magnesium absorption in the distal convoluted tubule (80). 

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