Tocolytics

The drugs which relax the uterine smooth muscles are known as tocolytics.

Indications:

To delay or postpone labor

Arrest threatened abortion

Dysmenorrhoea

Delaying the labor is needed to allow foetus to mature, to initiate glucocorticoid therapy for foetal lung maturation, to transfer the mother in labor to a centre with proper facilities

The drugs used are

1. Selective beta 2 adrenergic agonist e.g. ritodrine, isoxsuprine

2. calcium channel blockers (CCB) e.g. nifedipine

3. Magnesium sulfate (i.v.)

4. Oxytocin antagonist, Atosiban

5. Misc. drugs e.g. nitrates, prgesterone, PG synthesis inhibitors (NSAIDS) , general anaesthetics (halothane) etc