Labetalol (Normodyne, Trandate)


Hypertension (see Hypertension)


Sinus Bradycardia (Sinus Bradycardia)

  • Labetalol May Exacerbate Bradycardia

Atrioventricular Heart Blocks

Hypotension (see Hypotension)

  • Labetalol May Exacerbate Hypotension

Cocaine Intoxication (see Cocaine)

  • Labetalol Has an Alpha/Beta Antagonism Ratio of 1:7 (Br Heart J, 1977) [MEDLINE]
    • For this Reason, Labetalol Used in the Setting of Cocaine Intoxication Has Not Been Demonstrated to Reverse Cocaine-Induced Coronary Artery Vasospasm (and Can Result in Unopposed α1-Adrenergic Receptor Stimulation)


Combined β-Adrenergic Receptor Antagonist (Beta Blocker) + α1-Adrenergic Receptor Antagonist (Alpha Blocker)


  • Hepatic: extensive (via CYP450)


  • Half-Life: 5-8 hrs


  • Feces: 50%
  • Renal: 50%


Oral (PO)

  • Dose
    • Start 100 mg BID
      • May Divide Dose TID Instead
    • Escalate in Increments of 200 mg Per Day q2-3 days (Max: 2400 mg/Day)

Intravenous (IV)

  • Dose: 10-80 mg IV q6 hrs

Intravenous Continuous Infusion

  • Dose: 2 mg/min (max dose: 300 mg)

Dose Adjustment

  • Hepatic: use with caution in liver disease
  • Renal: none

Use in Pregnancy (see Pregnancy)

  • xxx

Use During Breast Feeding

  • xxxx

Adverse Effects

Allergic Adverse Effects

Cardiovascular Adverse Effects

Atrioventricular Heart Blocks

Sinus Bradycardia (see Sinus Bradycardia)

  • xxx

Congestive Heart Failure (CHF) (see Congestive Heart Failure)

  • xxx

Hypotension (see Hypotension)

  • xxxx

Syncope (see Syncope)

  • xxx

Gastrointestinal/Hepatic Adverse Effects

Neurologic Adverse Effects

Otolaryngologic Adverse Effetcts

Pulmonary Adverse Effects

Renal Adverse Effects

  • Elevated Blood Urea Nitrogen (BUN) and Creatinine (Cr)

Rheumatologic Adverse Effects

Other Adverse Effects

  • Ejaculatory Dysfunction
  • Intraoperative Floppy Iris Syndrome

Adverse Effects with Abrupt Discontinuation