Vomiting/nausea in the emergency room? 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, the median visual analog pain (VAS) score for abdominal pain in the patients receiving haloperidol fell from 5 to 0, compared with a fall in the VAS score from 6 to 3.5 in the ondansetron group (P=0.0006), reported Jessica McCoy, MD, of Western Michigan University’s Homer Stryker School of Medicine in Kalamazoo.

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

“[Haloperidol] is definitely a drug that will help young patients with benign abdomens who come in with vomiting and generalized abdominal pain,” she said MedPage today.

Of 384 patients with nausea and pain who were evaluated for inclusion in the study, 312 were excluded based on 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 ondansetron intravenously.

Exclusion criteria included abnormal blood pressure, fever greater than 100.4 °F, 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 an antiemetic in the Past 8 hours and nausea or vomiting associated with dizziness.

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

Haloperidol dose halving seemed to prevent the common side effects of anxiety, sedation and agitation, McCoy added.

Adverse reactions that had resolved by the time of discharge from the ED included three cases of anxiety/agitation and one case of tongue swelling in the haloperidol group, and isolated cases of agitation, drowsiness, and sore throat in the ondansetron group.

McCoy noted that ED patients report nausea and vomiting very frequently. Collectively, the problems are one of the top five most common complaints in the emergency department, and a diagnosis can be elusive when nothing needs urgent attention, she explained. “There’s this whole list of things that could make you feel a little bad but get better on their own.”

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

ED doctors 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 designed for people who are actively vomiting.”

McCoy said the new study follows on from her previous research showing haloperidol to be beneficial in the treatment of severe benign headaches.

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

McCoy noted that her facility’s ED physicians continue to consider alternatives to ondansetron, such as haloperidol, in appropriate cases, particularly in patients with anxiety. However, haloperidol is not suitable, she warned, for more complex cases such as patients with a rigid abdomen, possible dissections or patients who need surgery.

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