Non-Narcotic Additives in Subarachnoid Block

Primary Recommendation: Clonidine

The American Society of Anesthesiologists recommends clonidine as the primary non-narcotic additive for subarachnoid block, with preservative-free formulations at doses of 1-2 micrograms/kg providing prolonged analgesia and enhanced block duration 1, 2, 3
Clonidine is the most evidence-based non-narcotic additive for spinal anesthesia, though guidelines primarily address epidural and peripheral nerve blocks rather than subarachnoid blocks specifically 1, 2, 3

Preservative-free clonidine at a dose of 1-2 micrograms/kg is recommended for pediatric guidelines for neuraxial blocks 1, 2, 3

Preservative-free formulations are mandatory for neuraxial administration, as recommended by the American Society of Anesthesiologists 1, 2, 3

For routine subarachnoid blocks requiring prolonged analgesia, use clonidine 1-2 micrograms/kg (or 30-75 micrograms in adults) as first-line additive, and ensure preservative-free formulation is used 1, 2, 3