Table 2

Drugs used in the treatment of arrhythmia and their safety during pregnancy and lactation

Drug classDrug nameSafety during pregnancyCompatible with breast feeding?
Rhythm/Rate control
Beta-blockersMetoprolol, propranolol, bisoprolol, atenololConsidered safe, but may cause risk of fetal bradycardia, hypoglycaemia and intrauterine growth restriction.
Atenolol: not preferable, possible teratogenicity in first trimester.
Yes; propranolol, metoprolol and labetalol are preferable
Calcium-channel blockersVerapamil, diltiazemProbably safe, induces tocolysis and may cause maternal hypotension and subsequent fetal distress.
Diltiazem: limited human data, possible teratogenicity in animals.
Cardiac glycosidesDigoxinConsidered safe, preferable in treating arrhythmia. Increased renal clearance may necessitate higher dosage to maintain therapeutic levels.Yes
Antiarrhythmic drugsAdenosineConsidered safe.Yes
Antiarrhythmic drugsAmiodaroneUnsafe, may cause fetal thyroid disorders, but use in acute treatment may be warranted.No
Antiarrhythmic drugsFlecainideCommonly used in the intrauterine treatment of fetal tachycardia in the second and third trimester, but safety in the first trimester is unclear due to reports of teratogenicity in animals.Unknown
Antiarrhythmic drugsLidocaineConsidered safe, may cause fetal bradycardia and acidosis.Yes
Antiarrhythmic drugsProcainimideConsidered safe.Yes
Antiarrhythmic drugsQuinidineMay cause fetal thrombocytopenia and preterm labour due to an oxytocic effect in high doses.Yes
Antiarrhythmic drugsSotalolConsidered safe, may cause fetal bradycardia and hypoglycaemia.No
Direct oral anticoagulantsApixaban, dabigatranContraindicated due to teratogenicity in animal studies and bleeding risks.No
Antiplatelet drugsAcetylsalicylic acid, clopidogrelAspirin: considered safe in a low dose (<150 mg).
Clopidogrel: limited human data show no harm, use for shortest duration possible.
Aspirin: yes
Clopidogrel: unknown
HeparinsLow molecular weight heparin, unfractioned heparinSafe for the fetus, but may cause maternal bleeding complications, in particular during delivery; plan dosage accordingly.Yes
Vitamin K antagonistsAcenocoumarol, fenprocoumon, warfarinUse in the first trimester may cause embryopathy and miscarriage, use at time of delivery may cause maternal and fetal bleeding complications.Yes
  • Based on the 2018 ESC guidelines for the management of cardiovascular diseases during pregnancy,11 Drugs in Pregnancy and Lactation31 and the FDA Pregnancy and Lactation Labelling Rule, Drugs and Lactation Database (LactMed).

  • ESC, European Society of Cardiology; FDA, Food and Drug Administration.