Plasma concentrations of the two enantiomers of tertatolol were determined by gc/ms. Deuterium labelling of one of the tertatolol enantiomers was used for chiral discrimination. 2. No isotope effects were observed following simultaneous oral administration of tertatolol and [2H9]tertatolol. 3. After intravenous administration of the pseudoracemate or of each enantiomer separately, (+)-tertatolol showed a lower total clearance and volume of distribution, compared to the (-) enantiomer. 4. After oral administration of the pseudoracemate or of each enantiomer separately, no substantial difference in bioavailability were observed between the enantiomers.
