Following Ketamine administration, which antiemetic option and dose is appropriate?

Following Ketamine administration, which antiemetic option and dose is appropriate?

• A. Phenergan 12.5 mg
• B. Phenergan 25 mg
• C. Zofran 4 mg
• D. Benadryl 50 mg

Answer: (A)

Ketamine can trigger nausea and vomiting, and the antiemetic chosen should be effective without adding unnecessary sedation or other risks during recovery. A low dose of promethazine provides reliable antiemetic action and adds a modest sedative effect that can help smooth ketamine recovery, without the higher sedation and anticholinergic burden seen with a larger dose. The 12.5 mg dose hits that balance well. Increasing to 25 mg raises the risk of prolonged sedation, slowed recovery, and other anticholinergic effects, which is less desirable in this setting. Ondansetron is effective, but in many protocols the combination of efficacy and safety with ketamine favors promethazine at a low dose. Diphenhydramine at 50 mg adds sedation and anticholinergic effects with less robust antiemetic protection in this context, making it less preferable. So, promethazine 12.5 mg is the best choice.

Ketamine can trigger nausea and vomiting, and the antiemetic chosen should be effective without adding unnecessary sedation or other risks during recovery. A low dose of promethazine provides reliable antiemetic action and adds a modest sedative effect that can help smooth ketamine recovery, without the higher sedation and anticholinergic burden seen with a larger dose. The 12.5 mg dose hits that balance well. Increasing to 25 mg raises the risk of prolonged sedation, slowed recovery, and other anticholinergic effects, which is less desirable in this setting. Ondansetron is effective, but in many protocols the combination of efficacy and safety with ketamine favors promethazine at a low dose. Diphenhydramine at 50 mg adds sedation and anticholinergic effects with less robust antiemetic protection in this context, making it less preferable. So, promethazine 12.5 mg is the best choice.