Can pheniramine (Avil) and dexamethasone (Dexa) be used during pregnancy?

Safety of Pheniramine (Avil) and Dexamethasone (Dexa) During Pregnancy

Dexamethasone should be avoided during pregnancy unless the potential benefit justifies the risk to the fetus, while there is insufficient evidence regarding pheniramine safety in pregnancy. 1

Dexamethasone in Pregnancy

Safety Profile

• Dexamethasone is not recommended during pregnancy unless medically necessary, as adequate human reproduction studies have not been done with corticosteroids 1
• The FDA drug label specifically states that therapy with corticosteroids during pregnancy should be used with great caution, weighing anticipated benefits against possible hazards to mother and fetus 1
• Infants born to mothers who received substantial doses of corticosteroids during pregnancy should be carefully observed for signs of hypoadrenalism 1

Recommendations for Corticosteroid Use

• If corticosteroids are needed during pregnancy, nonfluorinated glucocorticoids are preferred over dexamethasone (which is fluorinated) 2
• For pregnant women requiring corticosteroid treatment, the lowest effective dose for the shortest possible time should be used to minimize exposure 2
• The 2020 American College of Rheumatology guidelines conditionally recommend continuing low-dose glucocorticoid treatment (≤10 mg daily of prednisone or nonfluorinated equivalent) during pregnancy if clinically indicated 2
• Higher doses of glucocorticoids (>20 mg daily of prednisone equivalent) should be tapered if possible, adding a pregnancy-compatible glucocorticoid-sparing agent if necessary 2

Risks Associated with Dexamethasone

• Prolonged use of corticosteroids during pregnancy may increase the risk of gestational diabetes and gestational hypertension/preeclampsia 3
• Corticosteroids appear in breast milk and could suppress growth, interfere with endogenous corticosteroid production, or cause other unwanted effects in the infant 1

Pheniramine (Avil) in Pregnancy

• There is insufficient specific evidence in the provided guidelines regarding the safety of pheniramine (Avil) during pregnancy
• Antihistamines as a class are not specifically contraindicated during pregnancy, but individual medications should be evaluated based on available evidence 2
• The European Respiratory Society/Thoracic Society of Australia and New Zealand (ERS/TSANZ) guidelines suggest that medication use during pregnancy needs to balance maternal risk versus benefit and fetal risk of therapy versus untreated maternal disease 2

General Principles for Medication Use in Pregnancy

• Approximately one in four women will be prescribed medication during pregnancy, but only about 10% of medications have sufficient data related to safe and effective use in pregnancy 4
• When considering any medication during pregnancy, healthcare providers should weigh the benefits of treating the condition against potential risks to the mother and fetus 2
• Untreated conditions during pregnancy can lead to significant complications including preterm birth, low birth weight, and spontaneous abortion 4

Clinical Decision-Making Algorithm

1. Assess medical necessity:

   • Determine if the condition requiring treatment poses significant risk to maternal or fetal health if left untreated 4
   • Consider alternative treatments with better established safety profiles 2

2. For dexamethasone specifically:

   • Use only if clearly indicated for a serious condition requiring corticosteroid therapy 1
   • Consider substituting with a nonfluorinated corticosteroid (like prednisone) which has more safety data in pregnancy 2
   • Use the lowest effective dose for the shortest duration possible 2

3. For pheniramine:

   • Consider alternative antihistamines with more established safety data in pregnancy 2
   • If needed, use for the shortest duration at the lowest effective dose 2

4. Timing considerations:

   • First trimester exposure carries the highest risk for structural teratogenicity 5
   • Unnecessary exposure to any medication should be avoided in the first trimester 5

5. Monitoring:

   • If either medication must be used, implement appropriate monitoring for potential maternal and fetal complications 1