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What is In Primi, in Preterm Labour, which of the following can be used as Tocolytic a) Ritodrineb) MgSo4c) Dexamethasoned) Propranolol and explain in detail?
Tocolytics are drugs to arrest preterm labor.
In case of preterm labor main problem is lungs of the fetus are not mature so the main treatment is antenatal steroid injection to the mother ,but steroids require a minimum waiting period of 24 hours to act, so in the meanwhile tocolytics are given to arrest uterine contractions.
Drugs with tocolytic effect but poor efficacy:

Ethyl alcohol

KDT 6/e, p 319

Nitrites
Atropine
Phenothiazine
General anaesthetics