Drug Mechanism of action Description Possiblecontraindications Maternal side effects Fetal and neonatal side effects Terbutaline (Brethine) β2 agonist Off-label use, FDA has advised that injectable terbutaline should only be used in urgent situations, and that the oral form of the drug should never be usedWhy do doctors still use terbutaline to delay preterm labor despite its major health risks? Retrieved on October 20th, 2020 Cardiac tachyarrhythmias,  prolonged tocolysis(>48 to 72 hours) diabetes Cardiac or cardiopulmonary arrhythmias, pulmonary edema, myocardial ischemia , hypertension, tachycardia, death Fetal tachycardia, hyperinsulinemia, hypoglycemia, myocardial and septal hypertrophy, myocardial ischemia Ritodrine (Yutopar) β2 agonist No longer FDA approved Poorly controlled thyroid disease and diabetes Metabolic hyperglycemia, hyperinsulinemia, hypokalemia, antidiuresis, altered thyroid function, physiologic tremor, palpitations, nervousness, nausea or vomiting, fever, hallucinations Neonatal tachycardia, hypoglycemia, hypocalcemia, hyperbilirubinemia, hypotension, intraventricular hemorrhage Fenoterol β2 agonist Diabetes Salbutamol (INN) or albuterol (USAN) β2 agonist Diabetes Hexoprenaline (Gynipral) β2 agonist Not FDA approved Hyperthyroidism, cardiovascular diseases, glaucoma, placental abruption, vaginal bleeding, inflammatory diseases of internal genitalia, 1st trimester of pregnancy, breastfeeding Vertigo, anxiety, tremor, hyperhidrosis, tachycardia, hypotension, hyperglycemia, edema Hypoglycemia, bronchospasm, anaphylactic shock Nifedipine (Procardia, Adalat) Ca2+ channel blocker Is one of the most commonly used tocolytic agents.Welcome to the Women's - The Royal Women's Hospital Victoria Australia Cardiac disease. It should not be used concomitantly with magnesium sulfate Flushing, headache, dizziness, nausea, transient hypotension. Administration of calcium channel blockers should be used with care in patients with renal disease and hypotension. Concomitant use of calcium channel blockers and magnesium sulfate may result in cardiovascular collapse None noted as yet Atosiban Oxytocin receptor antagonist Fewer side effects than β2 agonists Indomethacin NSAID Late pregnancy (ductus arteriosus), significant renal or hepatic impairment Nausea, heartburn Constriction of ductus arteriosus, pulmonary hypertension, reversible decrease in renal function with oligohydramnios, intraventricular hemorrhage, hyperbilirubinemia, necrotizing enterocolitis Sulindac NSAID Coagulation disorders or thrombocytopenia, NSAID-sensitive asthma, other sensitivity to NSAIDs Magnesium sulfate Myosin light chain inhibitor Shown to be ineffective for delaying birth or stopping early birth. Meta-analyses have failed to support it as a tocolytic agent Absolute contraindication: myasthenia gravis. Use as a tocolytic agent may result in death of the fetus or infant. Flushing, lethargy, headache, muscle weakness, diplopia, dry mouth, pulmonary edema, cardiac arrest Lethargy, hypotonia, respiratory depression, demineralization with prolonged use Ethanol GABAA receptor PAM Shown to be ineffective. Was a frequently used tocolytic in the mid-20th century, but later double-blind studies found it was not effective.
Drug Mechanism of action Description Possiblecontraindications Maternal side effects Fetal and neonatal side effects Terbutaline (Brethine) β2 agonist Off-label use, FDA has advised that injectable terbutaline should only be used in urgent situations, and that the oral form of the drug should never be usedWhy do doctors still use terbutaline to delay preterm labor despite its major health risks? Retrieved on October 20th, 2020 Cardiac tachyarrhythmias, poorly controlled diabetes mellitus, hyperthyroidism, prolonged tocolysis(>48 to 72 hours) American College of Obstetricians and Gynecologists’ Committee on Practice Bulletins—Obstetrics. Practice Bulletin No. 171: Management of Preterm Labor. Obstet Gynecol. 2016 Oct;128(4):e155-64. doi: 10.1097/AOG.0000000000001711. PMID: 27661654. diabetes Tachycardia, palpitations, hypotension, dyspnea, chest pain, hypokalemia, hyperglycemia, lipolysis, pulmonary edema, myocardial ischemia Gyetvai K, Hannah ME, Hodnett ED, Ohlsson A. Tocolytics for preterm labor: a systematic review. Obstet Gynecol. 1999 Nov;94(5 Pt 2):869-77. doi: 10.1016/s0029-7844(99)00329-4. PMID: 10546776. Fetal tachycardia, hyperinsulinemia, hypoglycemia, myocardial and septal hypertrophy, myocardial ischemia Ritodrine (Yutopar) β2 agonist No longer FDA approved Poorly controlled thyroid disease and diabetes Metabolic hyperglycemia, hyperinsulinemia, hypokalemia, antidiuresis, altered thyroid function, physiologic tremor, palpitations, nervousness, nausea or vomiting, fever, hallucinations Neonatal tachycardia, hypoglycemia, hypocalcemia, hyperbilirubinemia, hypotension, intraventricular hemorrhage Fenoterol β2 agonist Diabetes Salbutamol (INN) or albuterol (USAN) β2 agonist Diabetes Hexoprenaline (Gynipral) β2 agonist Not FDA approved Hyperthyroidism, cardiovascular diseases, glaucoma, placental abruption, vaginal bleeding, inflammatory diseases of internal genitalia, 1st trimester of pregnancy, breastfeeding Vertigo, anxiety, tremor, hyperhidrosis, tachycardia, hypotension, hyperglycemia, edema Hypoglycemia, bronchospasm, anaphylactic shock Nifedipine (Procardia, Adalat) Ca2+ channel blocker Is one of the most commonly used tocolytic agents.Welcome to the Women's - The Royal Women's Hospital Victoria Australia Cardiac disease. It should not be used concomitantly with magnesium sulfate Flushing, headache, dizziness, nausea, transient hypotension. Administration of calcium channel blockers should be used with care in patients with renal disease and hypotension. Concomitant use of calcium channel blockers and magnesium sulfate may result in cardiovascular collapse None noted as yet Atosiban Oxytocin receptor antagonist Fewer side effects than β2 agonists Indomethacin NSAID Late pregnancy (ductus arteriosus), significant renal or hepatic impairment Nausea, heartburn Constriction of ductus arteriosus, pulmonary hypertension, reversible decrease in renal function with oligohydramnios, intraventricular hemorrhage, hyperbilirubinemia, necrotizing enterocolitis Sulindac NSAID Coagulation disorders or thrombocytopenia, NSAID-sensitive asthma, other sensitivity to NSAIDs Magnesium sulfate Myosin light chain inhibitor Shown to be ineffective for delaying birth or stopping early birth. Meta-analyses have failed to support it as a tocolytic agent Absolute contraindication: myasthenia gravis. Use as a tocolytic agent may result in death of the fetus or infant. Flushing, lethargy, headache, muscle weakness, diplopia, dry mouth, pulmonary edema, cardiac arrest Lethargy, hypotonia, respiratory depression, demineralization with prolonged use Ethanol GABAA receptor PAM Shown to be ineffective. Was a frequently used tocolytic in the mid-20th century, but later double-blind studies found it was not effective.
A
poorly controlled diabetes mellitus, hyperthyroidism,
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diabetes Cardiac or cardiopulmonary arrhythmias,
American College of Obstetricians and Gynecologists’ Committee on Practice Bulletins—Obstetrics. Practice Bulletin No. 171: Management of Preterm Labor. Obstet Gynecol. 2016 Oct;128(4):e155-64. doi: 10.1097/AOG.0000000000001711. PMID: 27661654. diabetes Tachycardia, palpitations, hypotension, dyspnea, chest pain, hypokalemia, hyperglycemia, lipolysis,
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, hypertension, tachycardia, death
Gyetvai K, Hannah ME, Hodnett ED, Ohlsson A. Tocolytics for preterm labor: a systematic review. Obstet Gynecol. 1999 Nov;94(5 Pt 2):869-77. doi: 10.1016/s0029-7844(99)00329-4. PMID: 10546776.