Glycerin 5.6g; per 5.5mL. <6yrs: use Pedia-Lax Liquid Glycerin Supps. ≥6yrs: 1 supp rectally daily. Results usually within 15–60min; reevaluate if ineffective.

The pharmacokinetics of promethazine administered in oral syrup and rectal suppositories were highly variable, but, in general, the suppositories produced a lower C max and later t max than the syrup.