Does Labetalol (antihypertensive medication) cause vomiting?

Does Labetalol Cause Vomiting?

Yes, labetalol can cause vomiting, though it occurs relatively infrequently as a documented adverse effect in clinical practice.

Incidence and Clinical Context

Documented Rates from FDA Drug Label

The FDA prescribing information for labetalol reports vomiting as an adverse effect with the following incidence rates 1:

• <1% in patients receiving 200mg daily doses
• 0% in patients receiving 300-600mg daily doses
• 1% in patients receiving 1,200mg daily doses
• 2% in patients receiving 1,600mg daily doses
• 3% in patients receiving 2,400mg daily doses

This demonstrates a clear dose-dependent relationship, with vomiting becoming more common at higher doses 1.

Context-Specific Occurrence

Intravenous administration appears to carry higher risk for vomiting compared to oral formulations 2, 3:

• When used for hypertensive emergencies via IV bolus injection, vomiting is listed among the more common side effects alongside nausea, epigastric discomfort, and scalp tingling 3
• The European Society of Cardiology guidelines specifically note that hydralazine (not labetalol) is associated with nausea/vomiting as a prominent adverse effect when used for hypertensive emergencies in pregnancy 2
• The JNC-7 guidelines list "vomiting, scalp tingling, bronchoconstriction, dizziness, nausea, heart block, orthostatic hypotension" as adverse effects of IV labetalol for hypertensive emergencies 2

Route of Administration Matters

Oral labetalol has substantially lower rates of gastrointestinal side effects 1, 4:

• In large therapeutic trials, nausea (6%) was more common than vomiting (<1%) at standard oral doses 1
• Research studies confirm that gastrointestinal disturbances occur but are generally mild with oral administration 4, 5

IV bolus administration produces more frequent and severe side effects 3:

• A study of 15 severely hypertensive patients receiving IV bolus labetalol reported nausea, vomiting, and epigastric discomfort as limiting factors in 4 patients 3
• The authors concluded that incremental IV infusion is preferred over bolus injection due to better tolerability 3

Clinical Implications

When to Expect Vomiting

Vomiting with labetalol is most likely in these scenarios:

• High-dose therapy (>1,200mg daily oral) 1
• IV bolus administration for acute hypertensive control 3
• Rapid dose escalation without adequate titration 1

Distinguishing from Other Causes

Important caveat: In pregnancy-related hypertension, vomiting may represent worsening pre-eclampsia rather than a drug side effect 2:

• Hydralazine's side effects (headache, nausea/vomiting) can mimic worsening pre-eclampsia 2
• While this warning specifically addresses hydralazine, clinicians should maintain vigilance when any pregnant patient on antihypertensives develops vomiting 2

Management Approach

If vomiting occurs with labetalol 1, 3:

• Reduce the dose if using high-dose oral therapy (>800mg daily)
• Switch from IV bolus to IV infusion if using parenteral administration 3
• Consider alternative agents (nifedipine, methyldopa) if vomiting persists despite dose adjustment 2
• Rule out other causes including worsening hypertensive emergency complications 2

Comparative Context

Labetalol's gastrointestinal tolerability profile is generally favorable compared to some alternatives 2:

• Hydralazine has more prominent nausea/vomiting as adverse effects 2
• Methyldopa causes peripheral edema and other side effects but gastrointestinal effects are not prominently featured 2
• Nifedipine primarily causes headache, flushing, and tachycardia rather than gastrointestinal symptoms 2