A pharmaceutically-acceptable aqueous solution which is isobaric or hyperbaric, and isotonic, with respect to cerebrospinal fluid (CSF), comprises a 1-alkyl-N-(2,6-dimethylphenyl)-2-piperidinecarboxamide anesthetic agent such as bupivacaine or levobupivacaine and a saccharide. If the amount of the anesthetic agent is no more than 0.75% w/v, a salt or another additional non-saccharide is present. Accordingly, the amount of the saccharide can be kept below that which would provide isotonicity in the absence of the additional non-saccharide.
