Is Spirómon (salbutamol) safe to use during pregnancy?

Spirómon (Spironolactone) in Pregnancy

Spironolactone is contraindicated during pregnancy and must be discontinued before conception due to its antiandrogenic effects that can cause feminization of male fetuses, particularly during the critical first 6-8 weeks of gestation when male sexual differentiation occurs. 1

Classification and Risk Profile

• Spironolactone is FDA Pregnancy Category C, meaning the FDA establishes it must be avoided in pregnant women or the woman must be warned of potential risk to a male fetus 1
• The European Society of Cardiology recommends avoiding aldosterone antagonists during pregnancy due to potential antiandrogenic effects in the first trimester 1
• The mechanism of harm involves spironolactone competing with dihydrotestosterone for androgen receptor binding and inhibiting enzymes in androgen biosynthesis, which can disrupt normal male genital development 2

Limited Human Safety Data

• From 6 reported cases of spironolactone exposure during pregnancy, 5 resulted in normal male genital development, but 1 case presented with ambiguous genitalia in a newborn whose mother received spironolactone until week 5 of gestation 1
• A recent 2024 case report documented a pregnant woman accidentally exposed to high-dose spironolactone (240 mg/day) at 16 weeks gestation for 1 week who delivered a healthy male infant with normal genitalia at 38 weeks, though this exposure occurred after the critical period of male sexual differentiation 2
• These limited data are insufficient to establish safety, and the drug remains contraindicated 1

Pre-Conception Planning Requirements

All women of childbearing age taking spironolactone must receive counseling about pregnancy avoidance and use reliable contraception, as recommended by the American Academy of Dermatology 1, 3

Discontinuation Protocol:

• Stop spironolactone before attempting conception to avoid exposure during the critical 6-8 week window of male sexual differentiation 1
• Pregnancy testing at baseline is mandatory due to the Category C designation 3
• Concomitant use of oral contraceptives or hormonal IUD is frequently recommended to prevent unplanned pregnancy 1, 3

Management of Underlying Conditions During Pregnancy

For Heart Failure:

• Spironolactone and other mineralocorticoid receptor antagonists must be avoided 1
• Alternative agents include hydralazine and long-acting nitrates as recommended by the American Heart Association 1
• Beta-1 selective beta-blockers are preferred, avoiding the first trimester if possible (note: atenolol must be avoided due to intrauterine growth restriction risk) 1
• The American College of Cardiology suggests that in women with severe heart failure where discontinuation poses significant maternal risk, pregnancy should be carefully planned with cardiology consultation and alternative agents maximized 1

For Hypertension:

• Substitute with pregnancy-safe antihypertensives like methyldopa or labetalol 1
• Diuretics should be used with caution as they can decrease placental blood flow 1

For Dermatologic Conditions (Acne/Hirsutism):

• No hormonal therapy for hirsutism should be used during pregnancy 1
• Transition to topical therapies or consider oral antibiotics for acne 1
• Focus on mechanical hair removal methods during pregnancy 1

Critical Clinical Pitfalls

• Unplanned pregnancy while on spironolactone requires immediate discontinuation and specialist consultation to assess individual fetal risk 1
• The critical window for antiandrogenic effects is the first 6-8 weeks, so early pregnancy detection is essential 1
• Do not confuse spironolactone (Spirómon) with spiramycin, an antibiotic used for toxoplasmosis that is NOT teratogenic and is safe in pregnancy 4