Possible Interaction: Caffeine and Propranolol

“PURPOSE This study was designed to … hypothesis that combined administration of propranolol … caffeine (Pr+C) would increase endurance performance compared with the administration of propranolol alone (Pr) if caffeine would be … increase plasma free fatty acid (FFA) availability and/or lower plasma potassium concentration compared with propranolol administration alone.”

“However, caffeine potentiates the teratogenic effect of other substances, such as tobacco, alcohol, and acts synergistically with ergotamine and propranolol to induce materno-fetal vasoconstrictions leading to malformations induced by ischemia.”

“The fetoputhic effects of caffeine were significantly reduced by pretreatment with propranolol at all dosages; and it was therefore hypothesized that the β-adrenergic actions of catecholamines caused to be released by caffeine induce fetal circulatory disturbance, which leads to fetal abnormalities.”

“In contrast, propranolol shifted the caffeine dose-response curve to the right and significantly increased the caffeine threshold in the MHS group.”

“The positive inotropic and the arrhythmogenic effects of caffeine could be diminished by pretreating the fibres with propranolol or Ca antagonists (diltiazem and verapamil).”

“In this study we aimed … posed by mixtures of caffeine … propranolol to the freshwater ecosystems of Spain; (ii) the sensitivity of freshwater copepod species to the two compounds; (iii) if … to freshwater copepods contributes to the environmental risk posed by the two compounds in the freshwater bodies of Spain.”

“Pretreatment with propranolol abolished the effects of caffeine on heart performance and neurohumoral activation during the early phase of endotoxemia.”

“We enhanced LV E(max) by intracoronary infusion of caffeine after beta-blockade with propranolol and compared this effect with that of calcium.”

“ Propranolol or nifedipine did not modify the negative inotropic action of cocaine, whereas this action was blocked by caffeine.”

“The discriminative effects of … mg/kg of caffeine were blocked dose-dependently and completely by alpha adrenergic receptor … drugs (phentolamine, prazosin and yohimbine) and were blocked partially by propranolol and by drugs having behavioral depressant properties (diazepam, pentobarbital and … adenosine analogs, R-(-)-N6-(2-phenylisopropyl)adenosine, cyclohexyladenosine, 2-chloroadenosine).”