Pediatrics absorption

Ziegler EE, Edwards BB, Jensen RE et al. 1978. Absorption and retention of lead by infants. Pediatr Res 12 29-34. 

MORAis M B, FESTE A, MILLER R G, LiFSCHiTZ c H (1996) Effect of resistant and digestible starch on intestinal absorption of calcium, iron, and zinc in infant pigs. Pediatr Res. 39 872-6. 

The majority of the information discussed to this point and most of the literature concerned with drug absorption involve studies performed in young, healthy (usually male) adults. In contrast, there is considerably less information concerning absorption in subjects at either end of the age spectrum (i.e., pediatric and geriatric populations). For a variety of reasons, one would expect the absorption process in the latter... 

G Levy, MH MacGillivray, JA Procknal. Riboflavin absorption in children with thyroid disorders. Pediatrics 50 896-900, 1972. 

WJ Jusko, N Khanna, G Levy, L Stern, SJ Yaffe. Riboflavin absorption and excretion in the neonate. Pediatrics 45 945-949, 1970. 

Drug absorption is highly variable in neonates and infants [21,22]. Older children appear to have absorption patterns similar to adults unless chronic illness or surgical procedures alter absorption. Differences in bile excretion, bowel length, and surface area probably contribute to the reduced bioavailability of cyclosporine seen in pediatric liver transplant patients [22a]. Impaired absorption has also been observed in severely malnourished children [22b]. A rapid GI transit time may contribute to the malabsorption of carbamazepine tablets, which has been reported in a child [23]. Selection of a more readily available bioavailable dosage form, such as chewable tablets or liquids, should be promoted for pediatric patients. 

Rectal Administration. The administration of drugs by a solid rectal dosage form (i.e., suppositories) results in a wide variability in the rate and extent of absorption in children [79]. This fact, coupled with the inflexibility of a fixed dose, makes this a route that should not be promoted for pediatric patients. At least one death involving a 7-month-old infant can be directly attributed to the use of solid rectal dosage form of a therapeutic dose of morphine [80]. 

M. Nowak, B. Brundhofer, and M. Gibaldi, Rectal absorption from aspirin suppositories in children and adults, Pediatrics, 54, 23 (1974). 

Chamey E, Sayre J, Coulter M. 1980. Increased lead absorption in inner city children Where does the lead come from Pediatrics 65 226-231. 

Landrigan PJ, Baker EL Jr, Feldman RG, et al. 1976. Increased lead absorption with anemia and slowed nerve conduction in children near a lead smelter. J Pediatr 89 904-910. 

Finally, drug absorption and excretion have not been evaluated in pediatric or geriatric populations. However, here again the tolerability of rifaximin in childhood and in the elderly has found to be extremely good [33]. 

Continued researeh into the development of sensitive and specific biomarkers of exposure and effect for 3,3 -dichlorobenzidine, and the validation of these biomarkers in occupationally exposed individuals would be valuable. Since at this point there are no validated biomarkers of exposure and effect in adults, it makes sense to focus efforts on occupationally exposed adults rather than children who are unlikely to be exposed. There are no data on interactions of 3,3 -dichlorobenzidine with other chemicals in children or adults. There are no pediatric-specific methods to reduce peak absorption for 3,3 -dichlorobenzidine... 

Ashkenazi AE, Berman SE. 1961. Experimental kerosene poisoning in rats Use of C labelled hendecane as indicator of absorption. Pediatrics 28 642-649. 

Mann MD, Pirie DJ, Wolfsdorf J. 1977. Kerosene absorption in primates. J Pediatr 91(3) 495-498. 

Wolfe BM, Brodeur AE, Shields JB. 1970. The role of gastrointestinal absorption of kerosene in producing pneumonitis in dogs. J Pediatr 76(6) 867-873. 

Studies indicate that isopropyl alcohol may be substantially better absorbed by the dermal route than had previously been believed, although significant toxicity by this route would require prolonged exposure. Delayed dermal absorption rather than inhalation may account for a number of pediatric poisonings that have occurred after repeated or prolonged sponged bathing with isopropyl alcohol to reduce fever. In several cases symptoms have included respiratory distress, stupor, and coma. Recovery was complete within 36 hours. Hypersensitivity characterized by delayed eczematous reactions have occasionally been observed after dermal contact with isopropyl alcohol. ... 

Amprenavir may be taken with or without food however, a high-fat meal decreases the absorption of amprenavir and should be avoided. Advise adult and pediatric patients not to take supplemental vitamin E since the vitamin E content of amprenavir capsules and oral solution exceeds the Reference Daily Intake (adults, 30 units pediatrics, approximately 10 units). 

Developmental differences in drug absorption between neonates, infants and older children are summarized in Table 1. It must be recognized that the data contained therein reflect developmental differences which might be expected in healthy pediatric patients. Certain conditions and disease states might modify the function and/or structure of the absorptive surface area(s). GI motility and/or systemic blood flow can further impact upon either the rate or extent of absorption for drugs administered by ex-travascular routes in pediatric patients. 

Even if a medication is available in multiple formulations and dosage forms, the prescriber must consider the absorption and distribution differences between adult and pediatric patients. Blood supply at injection or infusion site, available blood supply for unit muscle mass, and skeletal muscle mass relative to body mass vary with patient age and size, causing drug absorption to vary, as well. A rapid intravenous bolus in a pediatric patient might result in acute toxicity a slow intravenous infusion, often required in neonates, can cause erratic, unreliable drug delivery in an older child. In addition, the volume of fluid tolerated for intravenous delivery varies significantly with the age and size of the patient. The blood supply and blood flow to and from the injection site are of prime importance since a gradual decrease in blood supply per unit muscle mass is seen with maturation. In addition, the skeletal muscle mass relative to... 

Bove KE, Daugherty CC, Tyson W, Mierau G, Heubi JE, Balistreri WF, Setchell KDR (2000) Bile acids synthetic defect and liver disease. Pediatr Dev Pathol 3 1-16 Hopfer U (2002) Digestion and absorption of basic nutritional constituents. In Devlin T (ed) Textbook of Biochemistry with Clinical Correlations. Wiley- Liss, New York, pp 1110-1113 Clark ML and Harries JT (1975) In McColl I, Sladen GE (eds) Intestinal Absorption in Man. Academic Press, New York, p. 195... 

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