Is Thorazine (chlorpromazine) effective for treating hiccups?

Chlorpromazine for Hiccups

Chlorpromazine is effective for treating persistent and intractable hiccups and remains the only FDA-approved medication specifically indicated for this condition, though baclofen and gabapentin may be preferred as first-line agents due to superior safety profiles. 1, 2

Treatment Algorithm

First-Line Pharmacotherapy

• Start with baclofen 5-10 mg three times daily or gabapentin 300 mg three times daily as initial therapy for persistent hiccups (>48 hours), as these agents demonstrate efficacy in randomized controlled trials with fewer adverse effects than chlorpromazine during long-term use. 1, 2
• Baclofen and gabapentin are particularly advantageous in rehabilitation settings and elderly patients where sedation and extrapyramidal symptoms must be minimized. 3

Second-Line Options

• Reserve chlorpromazine 25-50 mg orally three to four times daily for cases where baclofen or gabapentin fail or when rapid symptom control is essential. 4, 5
• Metoclopramide 10-20 mg orally or IV every 4-6 hours represents another evidence-based alternative supported by randomized controlled trial data. 1, 2

Chlorpromazine-Specific Dosing

• For acute treatment: 25-50 mg orally or 12.5-25 mg IV/IM every 3-4 hours until hiccups resolve, then taper to maintenance dosing. 4, 5
• The optimal therapeutic range is 12.5-400 mg/day, though modern practice favors lower doses (25-50 mg) to minimize adverse effects. 5

Critical Safety Considerations with Chlorpromazine

Cardiovascular Monitoring

• Monitor QTc interval before initiating therapy and avoid combining with other QT-prolonging medications, as chlorpromazine significantly increases arrhythmia risk. 5, 6
• Check for orthostatic hypotension and sinus tachycardia, particularly in elderly patients who have heightened fall risk. 5

Neurological Adverse Effects

• Extrapyramidal symptoms occur more frequently with chlorpromazine than atypical antipsychotics, including dystonic reactions, akathisia, and pseudo-parkinsonism. 5
• These side effects are particularly problematic in rehabilitation patients where motor function is critical to recovery. 3

Special Population Adjustments

• Start with 12.5-25 mg in elderly and debilitated patients due to increased sensitivity to anticholinergic effects, sedation, and extrapyramidal symptoms. 5
• Elderly patients require closer monitoring for falls secondary to orthostatic hypotension and excessive sedation. 5

When Chlorpromazine Is Most Appropriate

• Use chlorpromazine when rapid symptom control is needed and the patient can tolerate potential sedation and cardiovascular effects. 1
• Consider chlorpromazine for breakthrough hiccups in palliative care settings where other agents have failed, using 12.5 mg IV every 4-12 hours or 25 mg rectally every 4-12 hours. 5
• Chlorpromazine may be preferred when hiccups are associated with terminal restlessness requiring concurrent sedation. 5

Common Pitfalls to Avoid

• Do not use chlorpromazine as automatic first-line therapy despite FDA approval—the evidence base for baclofen and gabapentin suggests better risk-benefit profiles for most patients. 1, 2, 3
• Avoid chlorpromazine in rehabilitation patients where sedation and extrapyramidal symptoms will impair functional recovery and therapy participation. 3
• Never combine chlorpromazine with multiple QT-prolonging agents without cardiac monitoring and risk assessment. 5, 6
• Do not continue chlorpromazine long-term without reassessing the need for therapy and considering transition to safer alternatives like baclofen or gabapentin. 1

Alternative Considerations

• Trial empiric anti-reflux therapy when gastroesophageal reflux disease is suspected as the underlying cause, as treating the etiology is most effective. 1
• Consider haloperidol 0.5-2 mg every 4-6 hours as an alternative antipsychotic with potentially fewer cardiovascular effects than chlorpromazine. 4
• Physical maneuvers (pharyngeal stimulation, breath-holding techniques) should be attempted for acute hiccups before pharmacotherapy. 7, 8