Possible Interaction: Caffeine and Theophylline

“Conclusion: Ca feine an d the ophylline in crease psychomotor performance measures of attention at low plasma concentrations in healthy elderly volunteers.”

“Plasma concentrations of caffeine were lower than those of theophylline (mean 5.76 and 8.72 mg l-1 respectively at 2 h post-drug.”

“Notwithstanding the mutual interference of theophylline and caffeine metabolism, the reduction in apparent total body clearance and elimination rate constant of theophylline by 29% and 31%, respectively, indicated a pronounced influence of concomitant administration of realistic amounts of caffeine.”

“Comparable peak increases in the forced expiratory volume in one second (FEV1), the forced expiratory flow during the middle …-75%), and Gaw/VL occurred at 120 minutes following aminophylline and the highest dose of caffeine, indicating that caffeine is an effective bronchodilator but … an equivalent molar dose of theophylline.”

“ Caffeine and theophylline , stimulants widely consumed by the humans, are antagonists.”

“ Caffeine and theophylline produced reversible inhibition of TREK-1 channels in a concentration-dependent manner.”

“Critical review of toxic manifestations due to exposure to relatively large doses of caffeine and theophylline indicates that such combined exposure may potentiate the toxic effects of either drug.”

“ Theophylline clearance is decreased by concomitant use of erythromycin, cimetidine, high-dose allopurinol, oral contraceptives, and caffeine.”

“ Methylxanthine drugs pentoxifylline (OR, 0.72; 95% CI, 0.59-0.89) and theophylline (OR, 0.77; 95% CI, 0.66-0.91), and the corticosteroid dexamethasone (OR, 0.72; 95% CI, 0.61-0.85) were associated with decreased odds of PD.”

“Guarana has been used for centuries as a stimulant in South America, due to its high caffeine content; it also contains xanthine alkaloids, such as theobromine and theophylline , which enhance the effects of caffeine.”