Spinal sensory and motor blockade by intrathecal doxylamine and triprolidine in rats.

Doxylamine or triprolidine produces a dose-dependent effect of spinal motor and sensory block. Triprolidine with a better nociception-selective action over motor block has a better potency than mepivacaine or doxylamine. Doxylamine and triprolidine produce longer durations than mepivacaine.