Treatment of Strep Throat in Pregnancy
Penicillin V 500 mg orally twice daily for 10 days is the first-line treatment for strep throat in pregnant women, offering proven safety for both mother and fetus with narrow-spectrum activity. 1
First-Line Antibiotic Therapy
Penicillin V remains the drug of choice with a recommended dosage of 500 mg orally twice daily for 10 days, based on its narrow spectrum of activity and decades of safety data in pregnancy 2, 1.
Amoxicillin 500 mg orally three times daily for 10 days is an acceptable alternative, particularly for young children who may better tolerate the suspension formulation 2, 1.
Both penicillin and cephalosporin antibiotics are considered the safest classes during pregnancy, with no documented fetal harm 1.
The twice-daily dosing of penicillin V is as effective as more frequent dosing schedules (three or four times daily) and significantly improves compliance 3, 4.
Management for Penicillin-Allergic Patients
Non-Anaphylactic Penicillin Allergy
Cefazolin is the preferred alternative for pregnant women with penicillin allergy who do not have a history of anaphylaxis, angioedema, respiratory distress, or urticaria 2, 1.
First-generation cephalosporins can be safely used in patients without immediate-type hypersensitivity to β-lactam antibiotics 2.
High Risk for Anaphylaxis
For pregnant women at high risk for anaphylaxis (history of anaphylaxis, angioedema, respiratory distress, or urticaria after penicillin or cephalosporin), clindamycin 300 mg orally four times daily for 10 days is recommended if susceptibility testing confirms the isolate is susceptible 1.
Erythromycin is an alternative option at 500 mg orally every 6 hours for 10 days, but erythromycin estolate should be avoided in pregnant women due to risk of cholestatic hepatitis, which occurs more frequently in pregnancy 2.
If susceptibility testing is unavailable or the isolate is resistant to clindamycin or erythromycin, vancomycin 1 g intravenously every 12 hours until delivery may be used 2.
Critical Antibiotics to Avoid in Pregnancy
The following antibiotics must be avoided during pregnancy due to fetal risks:
- Tetracyclines (including doxycycline) 1
- Aminoglycosides 1
- Trimethoprim-sulfamethoxazole 1
- Fluoroquinolones 1
Essential Clinical Considerations
Diagnostic Confirmation
Treatment should only be initiated after positive throat culture or rapid antigen detection testing (RADT) for group A streptococci 1.
Withholding antibiotics in patients with negative microbiological tests is a quality care indicator 1.
Treatment Duration and Compliance
A full 10-day course is mandatory to prevent rheumatic fever and ensure bacterial eradication, regardless of symptom improvement 1.
Therapy can be safely postponed up to 9 days after symptom onset and still prevent acute rheumatic fever 2.
Early initiation of antimicrobial therapy results in faster resolution of symptoms, typically within 24 hours, and reduces suppurative complications 2, 5.
Important Pitfalls to Avoid
Do not treat asymptomatic carriers, as antimicrobial therapy is much less effective at eradicating group A streptococci from carriers than from patients with acute infections 1.
Do not use antibiotics before the intrapartum period to treat colonization, as this is ineffective and may cause adverse consequences 2.
Once-daily dosing of penicillin is associated with a 12 percentage point lower cure rate compared to more frequent dosing and should not be used 4.