The present invention relates to an acetaminophen injectable aqueous solution for use in the treatment or in the prevention of pain by spinal administration, wherein said acetaminophen injectable solution is supersaturated, substantially free of preservatives, and/or additives and/or co-solvents, and comprises a solvent which is degassed or substantially oxygen or air free. The invention addresses a need for prolonging the analgesic effect of formulations delivered by spinal administration. In certain embodiments, the acetaminophen injectable aqueous solution is administered simultaneously, separately or sequentially with a local anaesthetic by spinal administration.
