Effects of oral theophylline and oral salbutamol in the treatment of asthma.

A double-blind randomised controlled trial was conducted to study the effects of oral theophylline alone compared with oral theophylline and salbutamol in a sample of asthmatic children. Each treatment was administered at maximum recommended dosage. Children treated with the theophylline and salbutamol combination had higher pulse rates, lower peak flow measurements, and depressed blood theophylline levels. These results suggest that when given at maximum oral dosage, theophylline and salbutamol in combination, tend to interact negatively producing tachycardia and reduced therapeutic function.