Are losartan, hydrochlorothiazide, atenolol, and citalopram (Celexa) safe to use during pregnancy, and how should they be managed?

Immediate Medication Changes Required in Pregnancy

All four medications—losartan, hydrochlorothiazide (HCTZ), atenolol, and citalopram (Celexa)—require immediate evaluation and likely discontinuation or substitution upon pregnancy confirmation, with losartan and HCTZ being absolutely contraindicated.

Critical Actions by Medication

Losartan: STOP IMMEDIATELY

Losartan must be discontinued as soon as pregnancy is detected 1. This angiotensin II receptor blocker (ARB) is FDA Pregnancy Category D and causes severe fetal toxicity including:

• Renal or tubular dysplasia
• Oligohydramnios (reduced amniotic fluid)
• Growth retardation
• Skull ossification disorders
• Lung hypoplasia
• Fetal death 2

These devastating effects occur primarily in the second and third trimesters 3. While first-trimester exposure may not strongly support teratogenic potential 2, the drug should be stopped immediately upon pregnancy confirmation to avoid second- and third-trimester fetopathy 3. Case reports document oligohydramnios resolving within 8 days of losartan discontinuation at 32 weeks gestation 4.

Hydrochlorothiazide (HCTZ): STOP IMMEDIATELY

Diuretics are generally not recommended during pregnancy 3. While they may be used safely at lower doses in specific circumstances (e.g., chronic kidney disease), they should not be first-line agents 5. The primary concern is reducing placental perfusion, which can compromise fetal growth 5. Discontinue HCTZ and avoid routine diuretic use in pregnancy 6.

Atenolol: SWITCH TO SAFER BETA-BLOCKER

Atenolol is specifically not recommended in pregnancy 3, 7. It is FDA Category D and associated with:

• Intrauterine growth retardation 5, 8
• Fetal growth restriction 7

While the ESC guidelines note that first-trimester data don't strongly support teratogenic potential 2, atenolol should be avoided 9. Switch to labetalol, which is safe and effective during pregnancy 9, 3, 10. Alternative beta-blockers include metoprolol (preferred over atenolol due to lower incidence of fetal growth retardation) 5.

Citalopram (Celexa): RISK-BENEFIT DISCUSSION REQUIRED

Citalopram is FDA Pregnancy Category C 11. The evidence shows:

First and Second Trimester:

• No apparent major teratogenic risk when used during embryogenesis 12
• One study of 125 first-trimester exposures found only 1 major malformation (0.9%) 12
• Normal pregnancy outcomes and neurodevelopment up to 1 year in prospective studies 13

Third Trimester Concerns:

• 4.2-fold increased risk of neonatal special-care nursery admission for poor neonatal adaptation syndrome 12
• Neonates may develop complications requiring prolonged hospitalization: respiratory distress, feeding difficulty, jitteriness, irritability, hypoglycemia, hypotonia, seizures 11
• Possible increased risk of persistent pulmonary hypertension of the newborn (PPHN), though data are limited 11

Management Decision: The decision to continue or discontinue citalopram requires shared decision-making weighing depression relapse risk against neonatal complications 11. Women who discontinue antidepressants during pregnancy have higher relapse rates 11. If continuing citalopram:

• Use the lowest effective dose
• Consider tapering in the third trimester to minimize neonatal adaptation syndrome 11
• Plan for neonatal monitoring at delivery 11

Recommended Antihypertensive Substitutions

First-line safe options for hypertension in pregnancy 3, 10, 7:

1. Labetalol (most commonly recommended)
2. Nifedipine (extended-release formulations)
3. Methyldopa (has longest-term infant outcome data but less well-tolerated) 9, 7

Alternative options 3:

• Amlodipine (lower evidence level)
• Clonidine (useful for hyperemesis with transdermal patch)

Blood pressure target during pregnancy: 110-135/85 mmHg to reduce maternal hypertension risk while minimizing fetal growth impairment 3.

Critical Monitoring

• Serial ultrasounds to assess amniotic fluid if there was any second/third trimester ARB exposure 1
• Fetal growth surveillance if beta-blocker exposure continues 9
• Neonatal monitoring for hypotension, oliguria, hyperkalemia if ARB exposure occurred 1
• Neonatal observation for poor adaptation syndrome if citalopram continued through third trimester 11

Common Pitfall to Avoid

Do not assume pregnancy must be terminated due to first-trimester ARB exposure 2. While ARBs should be avoided, positive outcomes have been described with first-trimester exposure. Close follow-up is required, but immediate discontinuation and monitoring are the appropriate responses rather than pregnancy termination.