Aminophylline 💊

📚 Related Subjects: | Atrial Fibrillation | Sinus Tachycardia | Sinus Arrhythmia | Multifocal Atrial Tachycardia | Resuscitation - Adult Tachycardia Algorithm

⚠️ Clinical Pearls: - 🚬 Smokers often need higher doses due to increased clearance. - 👴 Elderly or those with CCF require smaller doses. - 📌 Always prescribe by brand – formulations differ in bioavailability. - 🔄 Multiple interactions: always cross-check with other medications.

📖 About

Always check the BNF link here.

• 💊 Aminophylline is a methylxanthine bronchodilator.
• Used mainly in acute severe asthma, COPD exacerbations, and (rarely) pulmonary oedema.

⚡ Mechanism of Action

• 🚫 Competitive, non-selective phosphodiesterase inhibitor.
• ⬆️ Increases intracellular cAMP → activates PKA → bronchodilation.
• 🛑 Inhibits TNF-α and leukotriene synthesis (anti-inflammatory effect).
• ⛔ Adenosine receptor antagonist (contributes to arrhythmogenic potential).

🩺 Indications

• Acute bronchospasm (asthma, COPD exacerbations).
• Occasionally used in pulmonary oedema (adjunct).

🔄 Interactions (not exhaustive – check BNF)

• 💊 Metabolised by hepatic CYP450 system.
• ⬇️ Levels with smoking, chronic alcohol use, enzyme inducers.
• ⬆️ Levels with liver disease, heart failure, elderly, macrolides (clarithromycin/erythromycin), fluconazole, ketoconazole, cimetidine, fluvoxamine.
• ⚡ Increased seizure risk with quinolones.

💊 Dosing

⚠️ Cautions

• 💓 Cardiac disease (↑ arrhythmia risk).
• ⚡ Epilepsy (lowers seizure threshold).
• 🔥 Hyperthyroidism, fever.
• 🧬 Porphyria.
• 🩸 Diabetes mellitus (can worsen glycaemic control).

🚫 Contraindications

• Hypersensitivity to aminophylline/theophylline.
• Acute porphyria.

💥 Side Effects

• 💓 Arrhythmias, palpitations.
• 🤢 Nausea, vomiting, abdominal pain.
• ⚡ Seizures, delirium, confusion.
• 😴 Insomnia, restlessness, tremor.

📑 References

• BNF: Aminophylline