This study clarified the effect of pharmacist‐led interventions to decrease the cost and inappropriate prescribing of parenteral paracetamol (PP). The prescribing pattern of PP was assessed at baseline and after pharmacist‐led interventions (educational and protocol interventions) in a teaching hospital in Tehran, Iran. Comparison of appropriate dosage form between baseline and postintervention assessments indicated a significant difference (55.6% vs 77.6%, respectively; p < 0.001). Educational intervention significantly improved the appropriate duration of PP administration from baseline to postintervention (29% vs 41.7%, respectively; p = 0.006), but had no significant effect on the appropriateness of dosing. The mean monthly number of vials used decreased considerably following the educational and protocol interventions (25% (p = 0.002) and 59% (p < 0.001) reductions, respectively). Thus, incorporating educational and protocol interventions could promote the appropriate prescription and rational use of PP and aid in reducing its financial burden.