Aminophylline

 Aminophylline

CATEGORY:     A methyl xanthine, that produces positive chronotropic, broncho dilation,    smooth muscle relaxation, CNS stimulation and inotropic activity and mild diuresis. Action may be mediated through inhibition of phosphodiesterase.

TRADE NAME: Aminophylline

PRESENTATION: 250mg/10mL ampoule

INDICATION: Bronchospasm, paroxysmal dyspnoea, 

                           Acute nocturnal cardiac dyspnoea, 

                           Bronchial asthma,

                           Cheyne-Stokes breathing, 

                           Pulmonary oedema

DOSAGE AND ADMINISTRATION: 

Usually a bolus dose followed by continuous infusion.

• Bolus: 5.6mg/Kg undiluted given at a maximum rate of 25mg/min 
• Infusion: 0.5 – 0.9 mg/Kg/hour in normal saline, glucose 5%, or Hartmann’s

Example: a 65Kg patient

• Bolus: 65 x 5.6 = 364mg Aminophylline 250mg/10mL ampoule = 14.5mL Aminophylline at 25mg/min = 14.5min giving time  
• Infusion:  65 x 0.9(say) = 58.5mg/hour

MONITORING:            

Aminophylline levels should be maintained between 10 – 20 mg/L (as Theophylline) 

Dosage adjustments may be required in liver disease, jaundice,cardiac dysfunction, obesity and in the elderly.

DRUG INTERACTIONS:

• Antacids, 
• Allopurinol, 
• Cimetidine, 
• Ranitidine,
• Ciprofloxacin, 
• Erythromycin, 
• Mexiletine, 
• Cefaclor,
• Isoniazid, 
• Norfloxacin, 
• Phenobarbitone, 
• Rifampicin

NURSING IMPLICATIONS:

Rapid administration can lead to: 

• agitation,
• convulsions, 
• tachycardia, 
• hypotension, 
• cardiac arrest

SIDE EFFECTS:            

• Tachycardia, 
• Palpitations, 
• Extrasystoles, 
• Increased pulse rate, 
• Circulatory failure, 
• Atrial and ventricular arrhythmia, 
• Insomnia, 
• Headache, 
• Irritability, 
• Reflex excitability, 
• Nausea, 
• Vomiting, 
• Abdominal cramps, 
• Increased urination,
• Albuminuria, 
• Tachypnoea