text: The plasma concentration of levobupivacaine is influenced by both the dosage and the method of administration. Additionally, absorption depends on the vascularity of the tissue. Maximum plasma concentration of 1.2 µg/mL is reached approximately 30 minutes post epidural injection. 
  Levobupivacaine undergoes biotransformation in the liver by the cytochrome P450 enzyme, specifically CYP1A2 and CYP3A isoforms as part of phase one biotransformation, thereby producing inactive metabolites. The major metabolite produced is 3-hydroxy-levobupivacaine and the minor one is desbutyl-levobupivacaine. Subsequently, levobupivacaine metabolites are further converted into glucuronic acid and sulphate ester conjugates as a part of phase two. Metabolic inversion of levobupivacaine is not observed. The extensive metabolism of levobupivacaine by the liver ensures that no unchanged drug is excreted via urine. As a result, in patients with renal dysfunction, only the inactive metabolites accumulate instead of the drug itself. 
  Research tracing radiolabelled levobupivacaine showed that 71% was recovered in urine and 24% was recovered in faecesl After the intravenous administration of 40 mg of levobupivacaine, the half-life was approximately 80 minutes and the rate of clearance was 651 ± 221.5 mL/min.