Effects of Ritodrine and Isoxsuprine With and Without Dexamethasone During Late Pregnancy

Transfer of Ritodrine and Norepinephrine in Human Placenta: in vitro Study

“…Ritodrine is a ß2-adrenoreceptor agonist used in obstetrics to prevent premature uterine contractions and to postpone delivery [3,6,11,12]. Knowledge regarding the placental transfer of this drug in vitro is scanty.…”

Combined Effect of Terbutaline and Betamethasone on Glucose Homeostasis in Preterm Labor

“…The effect of the glucocorticoid alone on the glucose levels, as demonstrated in the control patients, is not clinically significant. How ever, the rise in glucose levels in combined therapy (terbutaline and betamethasone) far exceeds the anticipated rise from terbutaline alone [11] and the rise in glucose seen with simultaneous administration of ritodrine and dexamethasone [21],…”

“…The acute eleva tion of blood glucose secondary to the intrave nous betamimetic tocolytic agents, however, has been well tolerated in a gravida with nor-mal glucose metabolism [1,[13][14][15], Subcuta neous administration of terbutaline also causes a rise in plasma glucose levels but this is felt to be transient in normal patients [16,17], Long-term oral therapy with terbutaline [ 18,19], but not ritodrine [20], has been asso ciated with impaired glucose tolerance. The treatment of nonlaboring third-trimester pa tients with intravenous ritodrine and dexamethasone has been shown to cause a slight increase in glycemia compared to patients treated with ritodrine alone [21], The obser vation was based on a 6-hour study period only. The combined effects of terbutaline and betamethasone on glucose homeostasis have not been well studied to date.…”

Tocolysis, β2 agonists and anaesthesia

“…Glycogenolysis is stimulated and the blood sugar increases, which stimulates insulin secretion. This, together with the direct effect of p,-agonists on the sodium/potassium pump, increases intracellular potassium and therefore hypokalaemia is an invariable accompaniment [6,7].…”