Table 3 Antiarrhythmic drugs.

Drugs	Safety profile	Listed complications	Breast feeding
Adenosine	Safe to use in pregnancy with no detectable effect on fetal cardiac rhythm	Pregnant women may respond to lower doses due to a reduction in adenosine deaminase	Safe as short half life
Atropine	Unknown but has been used for resuscitation	Insufficient data	Unknown
Amiodarone	Only for short term use in emergencies	If prolonged use; fetal hypo‐ and hyperthyroidism, goitre, IUGR, prematurity	Avoid
β‐blockers	Avoid atenolol in first trimester because of concern over IUGR	IUGR, bradycardia, apnoea, hypoglycaemia, hyperbilirubinaemia	Safe
Digoxin	Good safety profile	Miscarriage and fetal death in toxicity	Safe
Diltiazem	Too little experience to comment	Skeletal abnormalities, IUGR, fetal death	Unknown
Disopyramide	Too little data to recommend regular use	Premature uterine contractions	Unknown
Flecainide	Limited literature for treatment of maternal arrhythmias; however, maternal ingestion used to treat fetal SVT	Insufficient data but no reported significant complications. Concerns over its pro‐arrhythmic potential in fetus have limited its use in past	Unknown
Lignocaine	Good	Fetal distress may occur in fetal toxicity	Safe
Quinidine	Good safety profile in pregnancy; however, not used because of concern over safety profile in non‐pregnant women	Rarely, mild uterine contractions, premature labour, neonatal thrombocytopenia, fetal VIIIn damage	Safe
Procainamide	Possibly as safe as quinidine short term in pregnancy	Chronic use may be associated with lupus‐like syndrome, gastrointestinal disturbance, hypotension, agranulocytosis	Safe
Propafenone	Unknown	Insufficient data	Unknown
Sotalol	Safe	Transient fetal bradycardia	Safe
Verapamil	Safe (1st choice class IV drug)	Rapid injection may cause maternal ↓ BP and fetal distress	Safe

BP, blood pressure; IUGR, intrauterine growth restriction; SVT, supraventricular tachyarrhythmia.