Vomiting/Nausea in the ED? Consider Haloperidol, Study Suggests

SAN FRANCISCO – Haloperidol may be a better option than the old standby ondansetron to treat certain patients with vomiting and nausea in the emergency department (ED), according to a small double-blind, randomized study presented here.

At 90 minutes, median abdominal pain Visual Analogue Scale (VAS) score fell from 5 to 0 in the patients who received haloperidol compared with a VAS score drop from 6 to 3.5 in the ondansetron group (P=0.0006), reported Jessica McCoy, MD, of Western Michigan University Homer Stryker School of Medicine in Kalamazoo.

Also at 90 minutes, median nausea VAS score fell from 7 to 0.5 in the haloperidol group versus 6 to 3.5 in the ondansetron group (P=0.0178), data presented at the American College of Emergency Physicians annual meeting showed.

“[Haloperidol] is definitely a drug that’s going to help young patients with benign abdomens who come in with vomiting and generalized abdominal pain,” she told MedPage Today.

Of 384 patients with nausea and pain evaluated for inclusion in the study, 312 were excluded due to screening criteria and 48 (ages 18-55) completed the study. A total of 22 were randomized to receive 2.5 mg of intravenous haloperidol (half the usual dose) and 26 to receive 4 mg of IV ondansetron.

Exclusion criteria included abnormal blood pressure, fever over 100.4ºF, acute trauma, QT >450 ms on cardiac monitor, altered mental status, chest pain, allergy to haloperidol or ondansetron, Parkinson’s disease, pregnancy or lactation, use of any antiemetic in the previous 8 hours, and nausea or vomiting associated with vertigo.

McCoy said that while there has been concern that haloperidol prolongs the QT interval, the researchers found no sign of a difference between the drugs. Among the 29 cannabis users in the study, haloperidol was not found to be superior at 90 minutes post-treatment, she said.

Halving the dose of haloperidol seemed to prevent common side effects of anxiety, sedation, and restlessness, McCoy added.

Adverse effects, which resolved by the time of discharge from the ED, included three cases of anxiety/restlessness and one case of tongue swelling in the haloperidol group and single cases of restlessness, sleepiness, and irritated throat in the ondansetron group.

McCoy noted that it is very common for ED patients to report nausea and vomiting. Together, the problems are one of the top five complaints in the ED, and a diagnosis may be elusive if it’s nothing that urgently needs treatment, she explained. “There’s this whole list of things it could be that make you feel lousy for a little bit but get better on their own.”

The rise of chronic cannabis use, meanwhile, has produced more cases of nausea and vomiting, she said.

ED physicians often turn to ondansetron, a drug developed to prevent nausea in chemotherapy patients, McCoy said. However, ondansetron “doesn’t work great. And it really wasn’t developed for people who were actively vomiting.”

McCoy said the new study follows up on her previous research showing that haloperidol had benefit as a treatment for severe benign headache.

She noted that the new study is small and was halted at the interim analysis due to the pandemic. At that time, ED waits had extended to 6 or 7 hours, she said, and some patients with nausea and vomiting gave up and went home.

McCoy noted that the ED physicians at her institution continue to turn to alternatives to ondansetron such as haloperidol in appropriate cases, especially in patients with anxiety. Haloperidol, however, is not appropriate, she cautioned, for more complex cases such as patients with rigid abdomens, possible dissections, or who have a need for surgery.

Like ondansetron, haloperidol is inexpensive, she added. “I hope [the new research] spurs more interest in studying this drug and its pain-relieving properties.”