In the treatment of adult violent patients when ketamine is unavailable, which combination of IM medications is used?

• A. Haldol: 10 mg IM and Benadryl: 25 mg IM
• B. Ketamine: 4 mg/kg IM
• C. Haldol: 5 mg IM and Benadryl: 50 mg IM
• D. Haldol: 5 mg IV and Benadryl: 50 mg IV

Answer: (C)

The main idea is using a rapid IM chemical restraint that combines an antipsychotic with an antihistamine to quickly calm an violently agitated adult when ketamine isn’t available. Haloperidol blocks dopamine receptors to reduce extreme agitation, while diphenhydramine helps prevent extrapyramidal side effects from haloperidol and adds some sedative effect. The combination of haloperidol 5 mg IM with diphenhydramine 50 mg IM provides rapid relief with a safer side-effect profile for this specific scenario, and it stays within the IM route guidelines for emergency restraint. Higher doses of haloperidol or using an IV route aren’t aligned with this practice, and ketamine isn’t an option here, which is why the IM haloperidol plus diphenhydramine pairing is the preferred choice.