Possible Interaction: Aspirin and Epinephrine

“At that time ASA had blocked the secondary phase of adrenaline-and ADP-induced platelet aggregation.”

“In 50% of healthy blood donors the intake of 75 mg ASA a day resulted in the prolongation of PFA-100 collagen/epinephrine closure time ( CEPI = (relevant to reduced platelet reactivity) of over 150 s, whereas 75% donors responded to 150 mg ASA-.”

“Otherwise, the daily dose of 150 mg ASA resulted in a prolonged CEPI merely in 23% of in IHD patients.”

“Arachidonic acid and epinephrine promoted a stronger platelet aggregation in aspirin nonresponders than in aspirin responders while taking 300 mg/day aspirin.”

“Meanwhile, aspirin significantly reduced platelet aggregation induced by collagen (61.4%) and epinephrine (21.9%) but not ADP-induced aggregation.”

“When adrenaline was used as the aggregating agent, the cyclo-oxygenase pathway was recruited in the increased reactivity seen in the third trimester of normal pregnancy, and was sensitive to inhibition by low dose aspirin.”

“ Aspirin 50 mg/day suppressed arachidonate-induced platelet aggregation and secondary phase aggregation after ADP and adrenaline.”

“Since the ocular hypotensive effect of topically applied epinephrine is inhibited by indomethacin, a cyclo-oxygenase inhibitor, these results suggest that this … mediated by the endogenous production of prostaglandins, or other cyclo-oxygenase products, and that the intraocular pressure of glaucoma patients undergoing epinephrine therapy may increase … or aspirin ….”

“Compared to placebo, aspirin induced a persistent increase in bleeding time (% difference 45.6 +/- 21.4, mean +/- SD) and a decrease in platelet aggregation by ADP, epinephrine , collagen and arachidonic acid.”

“Since the platelets of patients with familial hypercholesterolaemia (FH) are hyperaggregable, the inhibitory effect of low-dose aspirin on platelet aggregation in response to adenosine diphosphate, collagen, adrenaline and arachidonic acid was tested in 9 young adult patients with FH and compared with that in 9 normal subjects.”

“MDA formation and platelet aggregation induced by adenosine disphosphate (ADP), collagen, and adrenaline were inhibited by doses of aspirin smaller than those inhibiting prostacyclin production.”