Tocolytic Drugs

Abstract

Abstract Tocolytic agents are agents that inhibit uterine contraction and allow enough time for corticosteroids to help with lung maturation. They are administered in cases of premature labor between the 22nd and 34th weeks of gestational age. They are divided into betamimetics, calcium channel blockers, cyclooxygenase inhibitors, and magnesium sulfate. Betamimetics can be used for a short period of time; their prolonged use is not recommended due to extensive side effects, including maternal death. They are associated with pulmonary edema, tachycardia, arrhythmias, hyperglycemia, and hypokalemia. Calcium channel blockers are more beneficial than β-adrenergic agents for prolongation of pregnancy, neonatal morbidity, and maternal side effects. Magnesium sulfate is not effective in delaying labor, and it does not have an advantage over other tocolytic agents when it comes to neonatal and maternal outcomes, as it shown in a Cochrane review. However, evidence suggests that magnesium sulfate reduces the severity of cerebral palsy in surviving infants if administered when the birth is anticipated before 32 weeks of gestation. It does prolong the action of depolarizing and nondepolarizing muscle relaxant and can have serious side effects if overdosed.