| Antibiotic | Pregnancy category | Dosage |
|---|---|---|
| Cephalexin (Keflex) | B | 250 mg two or four times daily |
| Erythromycin | B | 250 to 500 mg four times daily |
| Nitrofurantoin (Macrodantin) | B | 50 to 100 mg four times daily |
| Sulfisoxazole (Gantrisin) | C* | 1 g four times daily |
| Amoxicillin-clavulanic acid (Augmentin) | B | 250 mg four times daily |
| Fosfomycin (Monurol) | B | One 3-g sachet |
| Trimethoprim-sulfamethoxazole (Bactrim) | C† | 160/180 mg twice daily |