Tocolytic agent

Tocolytic agents are medications used to suppress premature labor (from the Greek tokos, childbirth, and lysis, loosening). They are given to pregnant women experiencing contractions before the 37th week of pregnancy, when delivery of the baby could potentially lead to health problems or even death.

Mechanism of Action

Tocolytic agents work by inhibiting the contractions of the uterus. They do this by blocking the action of certain hormones or by relaxing the smooth muscle of the uterus. The exact mechanism of action varies depending on the specific drug used.

Types of Tocolytic Agents

There are several different types of tocolytic agents, each with their own mechanism of action. These include:

• Beta-2 adrenergic agonists: These drugs, such as terbutaline, stimulate the beta-2 adrenergic receptors in the uterus, leading to relaxation of the smooth muscle.

• Calcium channel blockers: Drugs like nifedipine inhibit the flow of calcium into the muscle cells of the uterus, preventing contractions.

• Prostaglandin inhibitors: These drugs, such as indomethacin, inhibit the production of prostaglandins, hormones that stimulate contractions.

• Oxytocin receptor antagonists: Drugs like atosiban block the action of oxytocin, a hormone that stimulates contractions.

Side Effects

Like all medications, tocolytic agents can have side effects. These can include nausea, vomiting, palpitations, chest pain, and in rare cases, pulmonary edema. The specific side effects vary depending on the drug used.

See Also

• Preterm birth
• Obstetrics
• Pharmacology