Mechanism
How Theophylline works
Nonselective phosphodiesterase inhibition and adenosine receptor antagonism increase cAMP and produce bronchodilation, with additional respiratory stimulant effects.
← Respiratory Pharmacology
METHNBRC High Yield5/5 Importance
Theophylline Respiratory Pharmacology Guide
Class, mechanism, indications, adverse effects, kinetics, exam traps, and NBRC-style study pearls.
Theophylline is a methylxanthine bronchodilator with a narrow therapeutic window. It is used less commonly today but remains important because serum levels must be monitored and toxicity can cause nausea, vomiting, tachyarrhythmias, and seizures. For NBRC-style questions, recognize theophylline toxicity and the need for therapeutic drug monitoring.
Clinical Pearl
What to remember
The board-style trap is toxicity: nausea, tachyarrhythmias, and seizures with elevated serum levels.
Kinetics
Onset, peak, and duration
1
Onset
Variable
2
Peak
Variable
3
Duration
Variable by formulation
Quick facts
- Subclass
- Methylxanthine
- NBRC importance
- 5/5
- Difficulty
- 4/5
- Brands
- Theo-24, Elixophyllin
Common indications
- Adjunct maintenance therapy for asthma
- Adjunct maintenance therapy for COPD
- Selected patients not controlled with inhaled therapy
Adverse effects
- Nausea
- Vomiting
- Tachycardia
- Arrhythmias
- Tremor
- Insomnia
- Seizures
Contraindications
- Hypersensitivity to theophylline or xanthine derivatives
Cautions and safety issues
- Narrow therapeutic window
- Monitor serum levels
- Use caution with arrhythmias
- Use caution with seizure disorders
- Use caution with hepatic impairment
- Many drug interactions
NBRC-style question
NBRC-style pharmacology review
A patient scenario involves patient with nausea and arrhythmia on chronic theophylline. Which medication concept should the respiratory therapy student recognize?
High-yield answer
Theophylline = narrow therapeutic window
Interactive practice
Practice in PharmaGenius
Master this medication through adaptive review of class, mechanism, indications, adverse effects, exam traps, and clinical scenarios. Missed concepts can later be surfaced for targeted remediation.
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MechanismPractice
Clinical usePractice
Adverse effectsPractice
ScenarioPractice
Common Exam Traps
These are the answer choices, mechanisms, or medication classes most commonly confused with this medication on RT school and NBRC-style exams.
- Inhaled corticosteroid
- Short-acting beta agonist
- Muscarinic antagonist
- Mucolytic
- Pulmonary vasodilator
High-Yield Clinical Scenarios
- Patient with nausea and arrhythmia on chronic theophylline
- Question requiring serum level monitoring
- Adjunct bronchodilator therapy
- Toxicity scenario with seizures
Related study paths
Continue building pharmacology mastery
Use this medication page as a reference, then reinforce it with interactive practice and related PulmTools study resources.