Aminophylline is a compound salt of theophylline and ethylenediamine. Its pharmacological action mainly comes from theophylline,and  ethylenediamine enhances its water solubility. Insoluble in methanol, ethanol, ether. This product has direct relaxation effect on respiratory tract smooth muscle, and its mechanism of action is relatively complex.Aminophylline is a compound of the bronchodilator theophylline with ethylenediamine in 2:1 ratio.Aminophylline is less potent and shorter-acting than theophylline. Its most common use is in the treatment of airway obstruction from asthma or COPD.
Aminophylline can be used as dicuretic and the medicine helping to relax the smooth muscle .The aminophylline can relax the bronchus and the smooth muscle of the blood vessel,inhibit the kidney tubules to reabsorb the sodium and the water and enhance the extraction of heart oedema and so on .It is usually used as mono-medicine.It is mainly used in medicine field.

A drug combination that contains theophylline and ethylenediamine. It is more soluble in water than theophylline but has similar pharmacologic actions. It's most common use is in bronchial asthma, but it has been investigated for several other applications