Theophylline

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General

  • Type: Bronchodilator
  • Dosage Forms: Oral
  • Common Trade Names: Elixophyllin, Theo-24, Uniphyl

Adult Dosing

  • 300-600mg PO q6-8h (immediate-release) or q12h (ER)
  • IV theophylline no longer recommended for use inpatient or in the ED due to lack of added benefit over other treatments and high risk of adverse events[1][2]

Pediatric Dosing

  • Apnea in neonate: 4 mg/kg IV load, then 2 mg/kg IV q12h
  • Pediatric theophylline doses for asthma are very complicated, and with the narrow therapeutic window, probably not even worth trying it!

Special Populations

  • Pregnancy Rating: C
  • Lactation: Probably Safe
  • Renal Dosing
    • Adult: no adjustment
    • Pediatric: <3 mo: decrease dose amount not defined; >3 mo: no adjustment
  • Hepatic Dosing
    • Adult: decrease dose amount not defined
    • Pediatric: decrease dose amount not defined

Contraindications

  • Allergy to class/drug
  • Known allergy to corn or corn products (IV form)
  • caution if PUD, active
  • caution if seizure disorder
  • caution if arrhythmias
  • caution if CHF
  • caution if pulmonary edema, acute
  • caution if cor pulmonale
  • caution if hepatic impairment
  • caution if hypothyroidism
  • caution if febrile
  • caution if sepsis with multi-organ failure
  • caution if shock
  • caution if smoking habit changes
  • caution if neonates or infants
  • caution in elderly patients

Adverse Reactions

See theophylline toxicity for overdose information

Serious

  • seizures
  • arrhythmias
  • hypotension, shock
  • exfoliative dermatitis

Common

  • nausea/vomiting, diarrhea
  • headache
  • insomnia, irritability, restlessness, tremor
  • diuresis, transient

Pharmacology

  • Half-life: 8h
  • Metabolism: liver; CYP450: 1A2, 2E1, 3A3
  • Excretion: urine (10% unchanged)
  • Mechanism of Action: exact mechanism unknown; increases cAMP; antagonizes adenosine receptors (methylxanthine)

See Also

References

  1. National Heart, Lung, and Blood Institute: Expert panel report 3: guidelines for the diagnosis and management of asthma. National Heart, Lung, and Blood Institute. Bethesda, MD. 2007. http://www.nhlbi.nih.gov/health-pro/guidelines/current/asthma-guidelines
  2. Kallstrom TJ. Evidence-based asthma management. Respir Care. 2004;49(7):783-92.