Tretinoin pharmacokinetics

Pharmacokinetics The transdermal absorption of tretinoin from various topical formulations ranged from 1 % to 31 % of applied dose, depending on whether it was applied to healthy skin or dermatitic skin. 

In vitro and in vivo pharmacokinetic studies with tretinoin cream and gel indicated that less than 0.3% of the topically applied dose is bioavailable. Circulating plasma levels of tretinoin are only slightly elevated above those found in healthy normal controls. Estimates of in vivo bioavailability ot Retin-A M/cro following single and multiple daily applications, for a period of 28 days with the 0.1 % gel, were... 

Side effects associated with use of topical tretinoin ointment include transient hyperemia, irritation, or burning. Ocular pharmacokinetic studies in rabbits show low levels of drug in the aqueous humor after topical application of [ H]-tretinoin, with major tissue uptake in the surface epithelium and the iris. Because retinoic acid has poor stability in the presence of light and oxygen and is insoluble in water, its formulations and clinical use are limited. Although it is capable of reversing squamous metaplasia and keratinization, these ocular surface changes are seen only in severe, not mild to moderate, cases of dry eye. 

Achkar, C.C. Bentel, J.M. Boylan, J.F. Scher, H.I. Gudas, L.J. Miller, W.H., Jr. Differences in the pharmacokinetic properties of orally administered all-trems-retinoic acid and 9-cis-retinoic acid in the plasma of nude mice. Drug Metab.Dispos., 1994, 22, 451—458 [gradient LOD 0.5 ng/mL extracted metabolites, isotretinoin, tretinoin, vitamin A]... 

Eckhoff, C. Chari, S. Kromka, M. Staudner, H. Juhasz, L. Rudiger, H. Agnish, N. Teratogenicity and transplacental pharmacokinetics of 13-cis-retinoic acid in rabbits. Toxicol.Appl.Pharmacol., 1994, 125, 34-41 [plasma acitretin (IS) SPE column temp 35 tissue extracted metabolites, isotretinoin, tretinoin]... 

Guiso, G. Rambaldi, A. Dimitrova, B. Biondi, A. Caccia, S. Determination of orally administered all-trans-retinoic acid in human plasma by high-performemce liquid chromatography. J.Chromatogr.B, 1994, 656, 239—244 [all-trans-retinyl acetate (IS) extracted metabolites, isotretinoin, tretinoin LOD 10 ng/mL pharmacokinetics non-interfering allopurinol, amikacin, aracytin, ceftazidime, ciprofloxacin, doxorubicin, fluconazole, prednisone]... 

Shelley, R. Price, J.C. Jun, H.W. Cadwallader, D.E. Capomacchia, A.C. Improved and rapid high-performance liquid chromatographic assay for 13-cis-retinoic acid or all-trans-retinoic acid. J.Pharm.Sci., 1982, 71, 262-264 [rat serum extracted isotretinoin, retinol acetate, tretinoin, vitamin A pharmacokinetics LOQ 100 ng mL]... 

Fluconazole inhibits the cytochrome P450 isoenzymes CYP3A4 and CYP2C9, which are amongst those involved in the oxidative metabolism of tretinoin, and it was suggested that this resulted in increased plasma levels of tretinoin. Another study has also shown that fluconazole may inhibit the ADPH-dependent cytochrome P450-mediated metabolism of tretinoin. Ketoconazole may similarly affect the pharmacokinetics of tretinoin. ... 

Vane, F.M. Stoltenborg, J.K. Bugge, C.J. Determination of 13-cis-retinoic add and its major metabolite, 4-oxo-13-cis-retinoic acid, in human blood by reversed-phase high-performance liquid chromatography. J.Chromatogr, 1982, 227, 471-484 [gradient whole blood extracted metabolites, isotretinoin, tretinoin, vitamin A LOQ 10 ng/mL pharmacokinetics]... 

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