Table 2.

Safety of antiarrhythmic drugs during pregnancy and breastfeeding. CNS: central nervous system; FDA: Food and Drug Administration; FGR: fetal growth restriction; FVII: factor VII; IUGR: intrauterine growth restriction; IV: intravenous; SVT: supraventricular tachycardia

DRUG NAME	COMPLICATIONS TO FETAL & NEONATAL	COMPLICATIONS TO PREGNANT WOMEN	FDA RISK CATEGORY	VAUGHAN-WILLIAMS CLASS	TERATOGENIC	USE DURING LACTATION
Adenosine	Consider fetal monitoring, possible small risk of transient fetal bradycardia	Dyspnea Bradycardia Pregnant women may respond to lower doses due to a reduction in adenoside deaminase	C	N/A	No	Safe due to short half-life
Digoxin	Low birth weight Fetal death in toxicity	Miscarriage Monitor maternal levels for toxicity	C	N/A	No	Safe
Lidocaine	Fetal distress may occur in fetal toxicity Bradycardia Acidosis Central nervous system toxicity	–	B	1B	No	Safe
Sotalol	Transient fetal bradycardia Hypoglycemia B-blocker effects Torsades de pointes	–	B	III	No	Safe, but caution advised
Verapamil	Safe (1st choice class IV drug) Trend toward decreased FGR Fetal bradycardia Heart block	Maternal hemodynamic (hypotension) instability if infused rapidly.	C	IV	No	Safe, but caution advised
Flecainide	Concerns over its pro-arrhythmic potential in fetus have limited its use in past	Limited literature for treatment of maternal arrhythmias; however, maternal ingestion used to treat fetal SVT	C	1C	No	Safe
Quinidine	Fetal VIIIn damage Neonatal thrombocytopenia Ototoxicity Premature birth Vestibulocochlear nerve toxicity Torsades de pointe	Rarely, mild uterine contractions	C	1A	No	Safe
Procainamide	Possibly as safe as quinidine short term in pregnancy Drug-induced lupus Torsades de pointes Gastrointestinal disturbance Hypotension Agranulocytosis	–	C	1A	No	Safe for short-term use, but caution advised
Propanolol	Neonatal bradycardia Growth retardation Apnea Small risk of FGR Hypoglycemia	–	C	II	No	Safe
Metoprolol	Neonatal bradycardia Growth retardation Apnea Small risk of FGR Hypoglycemia	–	C	II	No	Safe
Labetalol	–	IUGR Bradycardia Apnea Hypoglycemia Hyperbilirubinemia	Unknown	Unknown	Unknown	Safe
Pindolol	–	–	B	II	No	Safe
Bisoprolol	Bradycardia Hypoglycemia	–	C	Unknown	Unknown	Safe
Disopyramide	–	Premature uterine contractions	C	1A	No	No
Diltiazem	IUGR Fetal death Skeletal abnormalities Fetal bradycardia Heart block Increased risk of FGR	Maternal hypotension	C	IV	Unknown	Safe, but caution advised
Propafenone	–	–	C	1C	No	No
Mexiletine	Bradycardia CNS effects Low Apgar score	–	C	1B	No	Safe, but caution advised
Ibutilide	Torsades de pointes		C	III	Unknown	Safe
Nadolol	Small risk of apnea FGR Hypoglycemia	–	C	II	No	Safe
Atenolol	Greater risk of FGR Cyanosis Low birth weight Growth retardation Neonatal bradycardia Hypoglycemia Other 3 -blockers are preferred over atenolol	–	D	II	No	No
Dofetilide	Human data lacking Torsades de pointes	–	C	III	Unknown	No
Dronedarone	Vascular and limb abnormalities Cleft palate	–	X	III	Yes	No
Amiodarone	Only for short-term use in emergencies. Fetal hypothyroidism Growth retardation Premature birth Goiter Growth retardation Bradycardia Prolonged QT interval IUGR	Bradycardia	D	III	Yes	No
Ivabradine	FGR Bradycardia Hypotension	Bradycardia	N/A	N/A	Yes	No
B-blockers	Avoid atenolol in first trimester due to concern over IUGR Bradycardia Apnea Hypoglycemia Hyperbilirubinemia	–	Unknown	Unknown	Unknown	Safe
Magnesium sulphate	Neuromuscular and/or respiratory depression Skeletal abnormalities	–	D	Unknown	Unknown	Safe
Carvedilol	–	–	C	II	No	Safe, but caution advised
Atropine	Fetal tachycardia Decrease in beat-to-beat variability of the fetal heart rate	Tachycardia	C	Unknown	No	No
Extensive Data/Safe to Use		Moderately Safe/Extensive Experience	Use with Caution in Pregnancy	Do Not Use in Pregnancy		Safety Data Lacking in Pregnancy