Table 372.2. Teratogenicity drug labeling now required by FDA
| Table 372-2. Antibiotic use during pregnancy | |
| ANTIBIOTIC | SPECIAL CONSIDERATIONS DURING PREGNANCY |
| Penicillin G | Safe in nonallergic patients; dosage requirements increased during pregnancy |
| Ampicillin | Dosage requirements increased during pregnancy; can lower urinary estriols; unconjugated serum estriol unaffected |
| Amoxicillin | Same as ampicillin |
| Cephalosporins | Dosage requirements increased during pregnancy; some cross-sensitivity in penicillin-allergic patients; may affect urinary estriols; no effect on unconjugated serum estriol |
| Erythromycin | Generally safe; placental transfer is erratic, but the fetal liver concentrates the drug |
| Tetracycline | Abnormal fetal teeth and bone development; increased risk of maternal liver and pancreatic disease; contraindicated in pregnancy |
| Chloramphenicol | May cause "gray baby syndrome"; avoid in pregnancy |
| Clindamycin | Fetal effects are unknown; may rarely cause pseudomembranous colitis in the mother |
| Vancomycin | Potential fetal ototoxicity; should be reserved for life-threatening infections in patients allergic to penicillin |
| Metronidazole | Mutagenic and carcinogenic in animals; may be necessary to use for symptomatic parasitic infections during second and third trimesters |
| Nitrofurantoin | Generally safe but has been rarely associated with hemolytic anemia in the newborn; few systemic effects |
| Quinolones | Contraindicated in pregnancy |
| Sulfonamides | Competes with bilirubin for albumin binding; should not be used in last trimester to avoid neonatal kernicterus |
| Trimethoprim | Folic acid antagonist; should be avoided during pregnancy unless no alternative available |
|
Aminoglycosides Amikacin Gentamicin Kanamycin Streptomycin Tobramycin |
Possible fetal and maternal ototoxicity and renal toxicity; maternal serum levels should be monitored closely but are usually in low range because of rapid renal clearance |