Besonderheiten der topischen Behandlung im Kindesalter

Abstract

Although the barrier function and thickness of the stratum corneum is fully developed in newborns, the infant shows numerous differences in cutaneous and systemic metabolism of topically applied substances in comparison to adults. This discrepancy between children and adults has been explained by the greater systemic availability due to the greater surface area to weight ratio in children. Several topically applied drugs such as hexachlorophene, phenol, salicylic acid and boric acid in high concentration or on large areas have caused toxic reactions and fatalities in infants. Therapeutic approaches to childhood dermatoses differ from these used in adults. These age-dependent differences concerning the topical application of glucocorticosteroids, urea and dyes are described for the treatment of atopic eczema. The development of innovative topical drugs may extend therapeutic options especially in children as shown by a new topical anesthetic cream improving the treatment of mollusca contagiosa, a common childhood problem. Finally, certain physiological differences should be considered in newborn and infant skin care.

Percutaneous Absorption of Salicylic Acid in Man after Topical Administration of Three Different Formulations

“…Our data and the data from the literature suggest that specific patient and age groups – e.g. the skin surface area per body weight ratio is 2.4 times higher in neonates (620 cm 2 /kg) than in adults (260 cm 2 /kg) [31]–, the area treated (in our study 600 cm 2 ), the vehicle and repeated application to diseased skin are risk factors for topical intoxication. The sudden, disproportionate increase in salicylate plasma concentrations into the toxic range from constantly high (borderline) levels, due to its inherent pharmacokinetic properties (see above), represents a major risk to develop a systemic intoxication.…”

Special features of topical and systemic dermatologic therapy in children

“…As the direct site of drug application, the skin is especially important. The epidermal perme‐ability barrier of the stratum corneum, which plays a central role in determining per‐cutaneous absorption, is comparable in the full‐term neonate (versus premature new‐borns) to that of an adult [2, 3, 4]. Anything that disrupts this barrier, such as excessive washing, burn/scald injuries, or bandage removal leads to increased absorp‐tion of topically applied agents.…”

“…A number of factors can lead to elevated blood levels of medication in children, which are associated with an increased risk of toxicity [2, 4, 9].…”

“…The treated area should remain uncovered for an hour after applica‐tion. For occlusion therapy using bandages or a dressing, attention should be paid to the amount applied related to surface area and the size of the child in order to avoid systemic side effects and early tachyphylaxis [5, 12]. Topical combination therapy can significantly alter absorption.…”

Therapieoptionen der Psoriasis im Kindes‐ und Jugendalter

“…In der Auswahl der geeigneten Therapieformen bei kindlicher Psoriasis sollten drei grundsätzliche Überlegungen berücksichtigt werden: (i) Die Unterschiede in der Hautstruktur und ‐eigenschaften wie z. B. der Permeabilität kindlicher und erwachsener Haut [4], die sich ebenfalls in unterschiedlicher pharmakokinetischer Dynamik widerspiegeln und deren Komplexität sicherlich eigene Abhandlungen über dieses Thema erforderlich machen [58]. Auch die Resorptionsrate unterscheidet sich aufgrund der unterschiedlichen Gewicht‐Oberflächen‐Ratio; so macht die Haut bei Neugeborenen etwa 13 % des Körpergewichts aus, beim Erwachsenen jedoch nur noch 3 % [11].…”