Drug Guide
Dyphylline
Classification
Therapeutic: Bronchodilator
Pharmacological: Methylxanthine derivative
FDA Approved Indications
- Management of chronic obstructive pulmonary disease (COPD)
- Bronchial asthma associated with bronchospasm
Mechanism of Action
Dyphylline acts as a phosphodiesterase inhibitor, leading to accumulation of intracellular cyclic AMP, resulting in relaxation of bronchial smooth muscle and dilation of airways.
Dosage and Administration
Adult: Typically 300-600 mg orally every 8-12 hours; dose may vary based on response and tolerability.
Pediatric: Use with caution; dosing based on weight and clinical response.
Geriatric: Start at lower end of dosing range due to potential for increased sensitivity and organ impairment.
Renal Impairment: Adjust dose; particular caution advised due to altered clearance.
Hepatic Impairment: Use with caution; hepatic metabolism may be impaired and necessitate dose adjustments.
Pharmacokinetics
Absorption: Well absorbed orally.
Distribution: Widely distributed; crosses the placenta.
Metabolism: Metabolized mainly in the liver.
Excretion: Primarily excreted in urine as metabolites.
Half Life: Approx. 4-8 hours, varies with age and organ function.
Contraindications
- Hypersensitivity to dyphylline or other methylxanthines.
- History of serious arrhythmias.
Precautions
- Use with caution in heart disease, peptic ulcer, hyperthyroidism, and seizure disorders. Monitor for adverse cardiac and CNS effects.
Adverse Reactions - Common
- Nausea, vomiting (Often)
- Headache, dizziness (Common)
- Gastrointestinal upset (Common)
Adverse Reactions - Serious
- Arrhythmias (Rare)
- Seizures (Rare)
- Hypersensitivity reactions (Rare)
Drug-Drug Interactions
- Cimetidine increases dyphylline levels.
- Caffeine may potentiate side effects.
Drug-Food Interactions
N/ADrug-Herb Interactions
N/ANursing Implications
Assessment: Monitor respiratory status, signs of toxicity, and blood levels if available.
Diagnoses:
- Impaired gas exchange
- Risk for toxicity.
Implementation: Administer with food if GI upset occurs, monitor for CNS and cardiac side effects.
Evaluation: Assess for improvement in respiratory symptoms and absence of adverse effects.
Patient/Family Teaching
- Take medication exactly as prescribed.
- Report signs of toxicity such as nausea, insomnia, palpitations, or seizures.
- Avoid caffeine and other methylxanthines to reduce side effects.
Special Considerations
Black Box Warnings:
- None currently; however, caution is advised regarding CNS and cardiac side effects.
Genetic Factors: No specific genetic considerations.
Lab Test Interference: May alter certain lab tests, including serum uric acid and blood glucose levels.
Overdose Management
Signs/Symptoms: Nausea, vomiting, seizures, tachycardia, hypotension, arrhythmias.
Treatment: Supportive care; activated charcoal if ingestion is recent; temporary control of arrhythmias and seizures as needed.
Storage and Handling
Storage: Store at room temperature away from light and moisture.
Stability: Stable under recommended conditions.