ISSN:
1432-1041
Keywords:
Timolol
;
β-adrenoceptor antagonist
;
transdermal
;
percutaneous absorption
;
skin
;
pharmacokinetics
;
bioavailability
;
adverse effects
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Medicine
Notes:
Summary The pharmacokinetic profiles of transdermal timolol 6 and 24 mg (as 5 and 20% w/v patches) was studied in four healthy young volunteers. To assess its bioavailability, the pharmacokinetics of an IV infusion of timolol maleate 5 mg was also determined in the same subjects. When the 20% (w/v) timolol patch was applied, the mean bioavailability was 74.4%. Plasma timolol concentrations were below the detection limit when a 5% patch was applied to the same skin area in all four subjects, except for one in whom the bioavailability was 23.6%. Weak erythema developed at the application site in all of the volunteers after application of the 20% (w/v) patch. However, erythema did not develop in any volunteer when the 5% patch was applied. The β-blocking effect was determined by exercise testing. Similar plasma levels generated similar changes in exercise-induced heart rate after the transdermal and intravenous administration of timolol.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00315551
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