Ecbolic drugs
Ecbolic drugs are agents that bring about increase in uterine contractions.
- Oxytocin: It is hormone of the posterior pituitary received from the hypothalamus. It has a major physiological role in milk let down and labor initiation.
- Clinical uses of oxytocin:
- For labor induction. Given by slow I/v in dextrose solution.
- For mIlk letdown . Only in agalactic animals
- For treatment of uterine inertia and for rapd involution of uterus.
- To arrest postparturient hemorrhage.
- For expulsion of retained placenta.
- The dose of oxytocin is 5 – 25 units in bitch, 75 – 100 units in cow / mare and 30 – 50 units in sow / ewe.
- Clinical uses of oxytocin:
- Oxytocics: Other agents which perform similar functions are also called oxytocics.
- Ergot alkaloids: Alkaloids from the fungus Claviveps purpurea viz. ergometrine, ergonovine have prominent effect on the uterus. Not preferred for induction of labour. Generally indicated for postparturient haemorrhage, rapid involution of uterus, retained placenta.
- PGF 2 alpha: Exerts potent stimulant action on myometrium. It is also popularly used for its luteolytic effect.
Tocolytic drugs
Tocolytics are agents that inhibit uterine contractions. They relax uterine smmoth muscle and may be used to delay labor and to stop threatened abortion.
- Beta-2 agonists: Salbutamol, terbutaline, isoxsuprine
- Calcium channel blockers: Nifedipine, diltiazem
- Oxytocin antagonist: Atosiban