Generic
Aminophylline
11 brands available in the market
At a glance
Aminophylline is a bronchodilator used for the treatment and prevention of asthma and chronic obstructive pulmonary disease (COPD). It relaxes airway muscles and makes breathing easier.
Description
Aminophylline is a combination of theophylline and ethylenediamine. Ethylenediamine is inactive and increases the solubility of theophylline in water. Theophylline relaxes bronchial smooth muscle. Suggested mechanisms are an increase in intracellular cAMP through inhibition of phosphodiesterase; adenosine receptor antagonism, prostaglandin antagonism and effects on intracellular calcium.
Indications
Treatment and prophylaxis of bronchospasm associated with asthma, emphysema and chronic bronchitis; treatment of cardiac asthma and left ventricular or congestive cardiac failure in adults.
Therapeutic class
Bronchodilator
Pharmacological class
Methyl Xanthine Derivative
Pharmacology
Aminophylline is a combination of theophylline and ethylenediamine. Ethylenediamine is inactive and increases the solubility of theophylline in water. Theophylline relaxes bronchial smooth muscle. Mechanisms include increased intracellular cAMP through phosphodiesterase inhibition, adenosine receptor antagonism, prostaglandin antagonism, and effects on intracellular calcium.
Mechanism of action
Aminophylline inhibits phosphodiesterase to increase intracellular cAMP, which relaxes bronchial smooth muscle and dilates airways, making breathing easier.
Dosage
Oral (Chronic bronchospasm):
- Adults: Initially 225-450 mg twice daily; increase if necessary
- Children (>3 years): 12 mg/kg/day in 2 divided doses; increase to 24 mg/kg/day after 1 week
Intravenous (Acute severe bronchospasm):
- Adults: Loading dose: 5 mg/kg (ideal body weight) or 250-500 mg (25 mg/mL) slow injection/infusion over 20-30 min; Maintenance: 0.5 mg/kg/hour
- Children: Loading dose same as adults; Maintenance: 6 months-9 years: 1 mg/kg/hour; 10-16 years: 0.8 mg/kg/hour
Administration
Take on an empty stomach (1 hour before or 2 hours after meals).
Swallow tablets whole; do not chew (due to tablet structure).
Missed dose
If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not double the dose.
Side effects
Common side effects: Gastric irritation, nausea, vomiting, diarrhea, hematemesis, epigastric pain, tremor, headache, irritability, restlessness, insomnia, twitching, palpitations, tachycardia, hypotension, flushing, albuminuria, diuresis, hematuria.
Serious (high doses): Ventricular arrhythmias, seizures, reactivation of peptic ulcer, circulatory failure, reflex hyperexcitability.
Precautions & warnings
- Used for prevention and treatment of asthma and COPD
- Does not work immediately; keep a rescue inhaler for emergencies
- Regular blood tests (potassium levels and drug levels) required
- Inform doctor if you have kidney, liver or heart disease
- Smoking history may require dose adjustment
- Do not discontinue without consulting your doctor
- Avoid high caffeine products (coffee, tea, dark chocolate)
Contraindications
- Hypersensitivity to xanthines or ethylenediamine
- Active peptic ulcer (may increase gastric secretion)
Drug interactions
- Antibiotics (erythromycin, ciprofloxacin): May decrease theophylline clearance
- Anti-epileptics (phenytoin, carbamazepine): May increase theophylline clearance
- Cimetidine: May increase theophylline levels
- Beta-blockers: May reduce bronchodilatory effect
- Allopurinol: May increase theophylline levels
Food interactions
Caution advised with alcohol consumption; alcohol may increase side effects.
Use in pregnancy
Use during pregnancy should be balanced against the risk of uncontrolled disease.
Pregnancy Category: C — always consult a doctor before taking during pregnancy.
Use in lactation
Safe during breastfeeding; does not pass into breast milk in significant amounts and is not harmful to the baby.
Pediatric use
Children >3 years: 12 mg/kg/day (divided doses), increase to 24 mg/kg/day after 1 week
6 months-9 years (IV): 1 mg/kg/hour; 10-16 years (IV): 0.8 mg/kg/hour
Geriatric use
Dose reduction may be necessary in elderly patients (decreased theophylline clearance).
Renal / hepatic impairment
Renal impairment: Caution required; dose adjustment may be needed.
Hepatic impairment: Caution required; dose adjustment may be needed (decreased theophylline clearance in liver disease).
Overdose effects
Overdose symptoms: nausea, vomiting, insomnia, tremor, tachycardia, seizures, ventricular arrhythmias. Treatment: symptomatic and supportive measures.
Storage conditions
Store below 30°C in a cool and dry place, protected from light. Keep out of reach of children.
Chemical structure
C₁₆H₂₄N₁₀O₄ (Theophylline + Ethylenediamine)