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
Mechanism, indications, adverse effects, kinetics, exam traps, and NBRC-focused guidance for respiratory therapy students and clinicians.
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 Pharmacology
Understand the medication before memorizing it
Start with mechanism, clinical pearls, onset, peak, duration, and deeper pharmacology explanations so the rest of the page has context.
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
Clinical Practice
How this medication is used at the bedside
Review common indications, expected adverse effects, contraindications, cautions, and safety issues in a clinically useful order.
Quick facts
- Subclass
- Methylxanthine
- NBRC importance
- 5/5
- Difficulty
- 4/5
- Brands
- Theo-24, Elixophyllin
5/5
NBRC importance
17
Study facts
0
Practice questions
2026
Updated
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
RT & NBRC Mastery
Respiratory therapy exam and bedside mastery
Move from reference knowledge into board-style reasoning, adaptive practice, common distractors, and high-yield clinical scenarios.
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
The Adaptive Exam Simulator
Use the complete guide on this page to learn the medication, then switch into the adaptive simulator to test yourself with scored practice, missed-concept review, and NBRC-style clinical reasoning.
ClassPractice
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
Guidelines
Guideline-based clinical context
Connect medication facts to the larger respiratory care guidelines, disease-state recommendations, and clinical decision frameworks.
Study Tools
Practice, recall, and retention
Use mini cases, flashcards, FAQs, and related concepts to turn the medication page into a high-retention study experience.
Practice Questions
Curated practice preview
Review a concise sample here, then use the adaptive simulator for all 0 board-style and clinical reasoning questions.
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.