Randomized Controlled Double-blind Trial Comparing Haloperidol Combined With Conventional Therapy to Conventional Therapy Alone in Patients With Symptomatic Gastroparesis

Objective: Gastroparesis is a debilitating condition that causes nausea, vomiting, and abdominal pain. Management includes analgesics and antiemetics, but symptoms are often refractory. Haloperidol has been utilized in the palliative care setting for similar symptoms. The study objective was to determine whether haloperidol as an adjunct to conventional therapy would improve symptoms in gastroparesis patients presenting to the emergency department (ED).

Study design and methods: This was a randomized, double-blind, placebo-controlled trial of adult ED patients with acute exacerbation of previously diagnosed gastroparesis. The treatment group received 5 mg of haloperidol plus conventional therapy (determined by the treating physician). The control group received a placebo plus conventional therapy. The severity of each subject's abdominal pain and nausea were assessed before intervention and every 15 minutes thereafter for 1 hour using a 10-point scale for pain and a 5-point scale for nausea. Primary outcomes were decreased pain and nausea 1 hour after treatment.

Results: Of the 33 study patients, 15 were randomized to receive haloperidol. Before treatment, the mean intensity of pain was 8.5 in the haloperidol group and 8.28 in the placebo group; mean pretreatment nausea scores were 4.53 and 4.11, respectively. One hour after therapy, the mean pain and nausea scores in the haloperidol group were 3.13 and 1.83 compared to 7.17 and 3.39 in the placebo group. The reduction in mean pain intensity therapy was 5.37 in the haloperidol group (p ≤ 0.001) compared to 1.11 in the placebo group (p = 0.11). The reduction in mean nausea score was 2.70 in the haloperidol group (p ≤ 0.001) and 0.72 in the placebo group (p = 0.05). Therefore, the reductions in symptom scores were statistically significant in the haloperidol group but not in the placebo group. No adverse events were reported.

Conclusions: Haloperidol as an adjunctive therapy is superior to placebo for acute gastroparesis symptoms.