Investigations on the pharmacokinetics of alpha-lipoic acid in healthy volunteers.
OBJECTIVE
The aim of the present study was to examine the pharmacokinetics of racemic alpha-lipoic acid in twelve healthy volunteers following single oral administration of 200 and 600 mg (Thioctacid 200 film tablets).


METHODS
Each film tablet contained 200 mg of alpha-lipoic acid. In addition, an injection solution containing 200 mg of alpha-lipoic acid was administered. Plasma concentrations of alpha-lipoic acid were determined using a validated reversed-phase HPLC method with electrochemical detection having a lower limit of quantitation of 1 ng/ml. The areas under curve (AUC) were 46.82 +/- 21.46 and 157.97 +/- 35.05 microg x min/ml for the oral and intravenous administration of 200 mg, respectively.


RESULTS
The AUC following oral administration of 600 mg was 157.83 +/- 35.82 microg x min/ml. The difference in mean t(1/2) for the two oral doses and the i.v. dose (in the range of 25.3-32.7 min) was not statistically significant.


CONCLUSIONS
The lack of a significant difference between values for apparent total plasma clearance for the 200 and 600 mg doses indicates non-saturable kinetics of alpha-lipoic acid in healthy volunteers in this dose range. The absolute bioavailability after the 200 mg dose was 29.1 +/- 10.3%.
Teichert
J
J
Institute of Clinical Pharmacology, University of Leipzig, Germany.
Kern
J
J
Tritschler
H J
HJ
Ulrich
H
H
Preiss
R
R
D000284:Administration, Oral; D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage / Q000493:pharmacokinetics*; D019540:Area Under Curve; D001682:Biological Availability; D002851:Chromatography, High Pressure Liquid; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D008063:Thioctic Acid / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*
D000975:Antioxidants; D008063:Thioctic Acid