Is levosolbutamol (albuterol) safe to use during pregnancy?

Levosalbutamol (Albuterol) in Pregnancy

Levosalbutamol (albuterol) is safe and recommended during pregnancy, with extensive evidence supporting its use as the preferred short-acting beta-agonist for asthma management. 1, 2

Safety Profile and Evidence Base

The benefits of maintaining asthma control with albuterol during pregnancy far outweigh any theoretical medication risks. 1, 2

• Albuterol has Australian Therapeutic Goods Administration Category A classification, indicating compatibility during pregnancy 1
• Clinical studies involving 6,667 pregnant women (including 1,929 with asthma and 1,599 who took beta2-agonists) demonstrate reassuring safety data with no increased risk of structural anomalies compared to the general population 1
• A large cohort study of 13,117 pregnancies found no increased risk of any congenital malformations (adjusted OR 1.04,95% CI 0.92-1.17) or major malformations (adjusted OR 0.93,95% CI 0.80-1.08) with short-acting beta-agonist use 3

Why Treatment is Essential

Uncontrolled asthma poses greater risks to the fetus than asthma medications. 1, 2

Untreated asthma increases risks of:

• Perinatal mortality 1
• Preeclampsia 1, 2
• Preterm birth 2
• Low birth weight infants 1, 2
• Maternal and fetal hypoxemia 2

Preferred Formulation and Dosing

Inhaled albuterol is the preferred route and formulation during pregnancy. 1

• For quick relief: 2-4 puffs via metered-dose inhaler as needed for symptoms 1
• For acute exacerbations: 2.5 mg via nebulization every 20 minutes for 3 doses, then every 1-4 hours as needed 1
• Short-acting beta-agonists are preferred over long-acting formulations during pregnancy due to more extensive safety data 1

Critical Caveat on Systemic Administration

Avoid oral or intravenous albuterol during pregnancy. 1

Systemic administration can cause:

• Maternal and fetal tachycardia 1
• Maternal hyperglycemia 1
• Neonatal hypoglycemia 1

Inhaled formulations do not produce these effects—a study of 12 pregnant women between 33-39 weeks showed no effects on maternal blood pressure, heart rate, uterine/umbilical artery blood flow, or fetal heart rate during the 2 hours after maximum recommended inhaled doses 4

Monitoring Requirements

Monthly evaluation of asthma control and lung function is mandatory throughout pregnancy. 1, 2

• Asthma improves in one-third of pregnant women and worsens in one-third, necessitating regular reassessment 1, 2
• If albuterol is needed more than twice weekly, this signals inadequate control requiring initiation or escalation of controller therapy (preferably inhaled budesonide) 1
• Involve obstetrical care providers in assessment and monitoring 1

FDA Labeling Considerations

The FDA label notes levosalbutamol is Pregnancy Category C, stating it should be used "only if the potential benefit justifies the potential risk to the fetus." 5 However, this conservative FDA classification should not deter appropriate use, as clinical guidelines from the American College of Allergy, Asthma, and Immunology and the National Asthma Education and Prevention Program explicitly support albuterol as first-choice therapy during pregnancy based on extensive human safety data 1

The FDA label also notes that racemic albuterol showed teratogenic effects (cleft palate) in animal studies at doses 2-20 times the maximum human dose, but these findings have not translated to human experience 5

Labor and Delivery

Albuterol can be used during labor for bronchospasm, but should not be used for tocolysis. 5

• Beta-agonists may interfere with uterine contractility 5
• Serious adverse reactions including maternal pulmonary edema have been reported when beta2-agonists are used for preterm labor management 5
• For asthma management during labor, the benefits clearly outweigh risks 5