Aminophyline is a combination of theophylline and ethylenediamine. Ethylenediamine is inactive; it 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.
It is used for the treatment and prophylaxis of bronchospasm associated with asthma, emphysema and chronic bronchitis. Also used for adults for the treatment of cardiac asthma and left ventricular or congestive cardiac failure.
Aminophyline is also used to associated treatment for these conditions: Acute Exacerbation of Chronic Bronchitis (AECB), Asthma, Bronchial Asthma, Bronchospasm, Chronic Bronchitis, Exacerbation of asthma
|Other Names||Aminofilina, Aminophyllin, Aminophylline, Aminophyllinum|
|Therapeutic Class||Methyl xanthine derivatives, Respiratory stimulants: analeptics, Theophylline & related drugs|
|Manufacturer||Popular Pharmaceuticals Ltd, Square Pharmaceuticals Ltd|
|Last Updated:||June 23, 2021 at 11:16 am|
Table Of contents
- Adult: As hydrate: Initially, 225-450 mg bid, increased if necessary.
- Child: >3 yr: As modified-release hydrate: 12 mg/kg daily increased to 24 mg/kg daily in 2 divided doses after 1 wk.
Intravenous:Acute severe bronchospasm:
- Adult: Loading dose: 5 mg/kg (ideal body weight) or 250-500 mg (25 mg/ml) by slow inj or infusion over 20-30 min. Maintenance infusion dose: 0.5 mg/kg/hr. Max rate: 25 mg/min.
- Child: Loading dose: same as adult dose. Maintenance dose: 6 mth-9 yr: 1 mg/kg/hr and 10-16 yr: 0.8 mg/kg/hr.
- Elderly: Dose reduction may be necessary.
- Hepatic impairment: Dose reduction may be necessary.
Tablets should be swallowed whole and not chewed because of the structure of the tablet.
The most common adverse effects are gastric irritation, nausea, vomiting, diarrhea, hematemesis, epigastric pain and tremor. These are usually early signs of toxicity; however, with high doses, ventricular arrhythmias or seizures may be the first signs to appear and reactivation of peptic ulcer, headache, irritability, restlessness, insomnia, twitching, convulsion and reflex hyperexcitability, palpitation, tachycardia, hypotension, circulatory failure, ventricular arrhythmias, and flushing, albuminuria, diuresis and hematuria. Also inappropriate ADH syndrome may occur.
Aminophyline should be given with caution to patients with peptic ulceration, hyperthyroidism, hypertension, cardiac arrhythmias or other cardiovascular disease, or epilepsy, as these conditions may be exacerbated. They should also be given withcaution to patients with heart failure, hepatic dysfunction, chronic alcoholism, acute febrile illness, and to neonates and the elderly, since in all of these circumstances theophylline clearance may be decreased, resulting in increases in serum-theophylline concentrations and serum half-life.
- Administer vitamin supplements. Aminophyline may reduce Vitamin B6 levels as an adverse effect. Consider supplementation.
- Avoid excessive or chronic alcohol consumption. Ingesting a large amount of alcohol may reduce aminophylline clearance, therefore increasing its serum concentration.
- Exercise caution with grapefruit products. Grapefruit inhibits CYP3A4 metabolism, which may increase the serum concentration of aminophylline.
- Exercise caution with St. John's Wort. This herb induces the CYP3A4 metabolism of aminophylline. Therefore it may reduce the serum concentration and effectiveness of aminophylline.
- Limit caffeine intake. Excessive caffeine intake with aminophylline may exacerbate caffiene-like side effects such as nausea, nervousness, irritability, insomnia and tremors.
- Take with food. This may reduce gastric irritation. Aminophyline absorption is slower when taken with food.
Volume of Distribution
- 0.3 to 0.7 L/kg
- 0.29 mL/kg/min [postnatal age 3-15 days]
- 0.64 mL/kg/min [postnatal age 25-57 days]
- 1.7 mL/kg/min [ 1-4 years]
- 1.6 mL/kg/min [4-12 years]
- 0.9 mL/kg/min [13-15 years]
- 1.4 mL/kg/min [16-17 years]
- 0.65 mL/kg/min [Adults (16-60 years), non-smoking asthmatics]
- 0.41 mL/kg/min [Elderly (>60 years). liver, and renal function]
- 0.33 mL/kg/min [Acute pulmonary edema]
- 0.54 mL/kg/min [COPD->60 years, stable non-smoker >1 year]
- 0.48 mL/kg/min [COPD with cor pulmonale]
- 1.25 mL/kg/min [Cystic fibrosis (14-28 years)]
- 0.31 mL/kg/min [Liver disease -cholestasis]
- 0.35 mL/kg/min [cirrhosis]
- 0.65 mL/kg/min [acute hepatitis]
- 0.47 mL/kg/min [Sepsis with multi-organ failure]
- 0.38 mL/kg/min [hypothyroid]
- 0.8 mL/kg/min [hyperthyroid]
Pregnancy & Breastfeeding use
Use of aminophylline in pregnant women should be balanced against the risk of uncontrolled disease.
Aminophyline should not be administered to patients with hypersensitivity to xanthines or ehylenediamine. It should not be administered to patients with active peptic ulcer, since it may increase the volume and acidity of gastric secretions.