ULTRACEF
Clinical safety rating: caution
Comprehensive clinical and safety monograph for ULTRACEF (ULTRACEF).
Cefadroxil, a first-generation cephalosporin, inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs), inhibiting transpeptidation and disrupting peptidoglycan cross-linking, leading to cell lysis. It is bactericidal against susceptible organisms.
| Metabolism | Cefadroxil is not significantly metabolized; it is primarily excreted unchanged in urine via glomerular filtration and tubular secretion. |
| Excretion | Approximately 90% of an oral dose is excreted unchanged in urine via glomerular filtration and tubular secretion; less than 1% is excreted in feces via biliary elimination. |
| Half-life | 0.5–1.2 hours in normal renal function; prolonged to 2–4 hours in severe renal impairment (CrCl <10 mL/min). |
| Protein binding | ~25% bound to plasma proteins (primarily albumin). |
| Volume of Distribution | 0.2–0.3 L/kg, indicating distribution primarily in extracellular fluid. |
| Bioavailability | Oral: approximately 90% (capsule and suspension). |
| Onset of Action | Oral: 0.5–1 hour; intramuscular: 15–30 minutes. |
| Duration of Action | 4–6 hours or longer with probenecid; clinically, dosing every 6–12 hours depending on infection severity. |
| Molecular Weight | 349.4 |
| Action Class | Cephalosporins: 3 generation |
| Brand Substitutes | Emrocef 250mg Injection, Solfix-O 250mg Injection, Deczone 250mg Injection, Accuzon 250 Injection, Zikit 250mg Injection, Xone Hospital 1000mg Injection, Ritecef 1000mg Injection, Cefaxone 1gm Injection, Trixon 1000mg Injection, Ceftrax 1000mg Injection |
250 mg orally every 6 hours or 500 mg orally every 12 hours for uncomplicated urinary tract infections; 1 g orally every 12 hours for complicated urinary tract infections.
| Dosage form | TABLET |
| Renal impairment | CrCl 30-50 mL/min: 250 mg every 8 hours; CrCl 15-29 mL/min: 250 mg every 12 hours; CrCl 5-14 mL/min: 250 mg every 24 hours; CrCl <5 mL/min: 250 mg every 48 hours. |
| Liver impairment | No dose adjustment required for mild to moderate hepatic impairment; not studied in severe impairment. |
| Pediatric use | Children >1 month: 25-50 mg/kg/day orally divided every 6-8 hours for urinary tract infections; maximum 1 g/day. |
| Geriatric use | Start at lower end of dosing range due to age-related renal decline; adjust dose based on creatinine clearance. |
| 1st trimester | No adequate studies in pregnant women. Animal studies have shown no evidence of teratogenicity, but use only if clearly needed. |
| 2nd trimester | No evidence of fetal harm in animal studies; use if clearly needed. |
| 3rd trimester | Avoid use near term due to potential for kernicterus in neonates (displaces bilirubin from albumin). |
Clinical note
Comprehensive clinical and safety monograph for ULTRACEF (ULTRACEF).
| Placental transfer | Cephradine crosses the placenta; measurable cord blood concentrations are achieved. |
| Breastfeeding | Cephradine is excreted into breast milk in small amounts. Use with caution in nursing mothers; potential for infant sensitization and diarrhea. |
| Lactation Rating |
■ FDA Black Box Warning
None.
| Serious Effects |
Hypersensitivity to cephradine or any cephalosporin antibioticHistory of severe immediate hypersensitivity reaction to penicillins or other beta-lactams (potential cross-reactivity)
| Precautions | Serious hypersensitivity reactions (anaphylaxis) may occur, especially in penicillin-allergic patients., Clostridium difficile-associated diarrhea (CDAD) ranging from mild diarrhea to fatal colitis., Dosage adjustment required in renal impairment (CrCl <30 mL/min) to avoid accumulation., Prolonged use may result in overgrowth of non-susceptible organisms including fungi., Cefadroxil may cause false-positive direct Coombs test and false-positive urine glucose tests with non-enzymatic methods. |
| Food/Dietary | No significant food interactions. Food may decrease GI upset but does not affect absorption significantly. Avoid alcohol for at least 72 hours after last dose due to potential disulfiram-like reaction (though rare with cephalosporins). |
Loading safety data…
| L2 (Safely compatible in breastfeeding, but limited data) |
| Teratogenic Risk | FDA Category B. No evidence of teratogenicity in animal studies. Inadequate human data; however, penicillins are generally considered low risk. First trimester: insufficient data; second and third trimesters: no known fetal harm. |
| Fetal Monitoring | Monitor for signs of hypersensitivity, diarrhea, and superinfection. In pregnancy, assess renal function and complete blood count periodically. |
| Fertility Effects | No adverse effects on fertility reported in animal studies. Human data lacking. |
| Clinical Pearls | Ultracef (cefadroxil) is a first-generation cephalosporin with a long half-life (1.2-1.5 hours) allowing once- or twice-daily dosing. It is not active against MRSA or enterococci. Use caution in penicillin-allergic patients (cross-reactivity ~5-10%). Dose adjust in renal impairment (CrCl <50 mL/min). Administer with food to reduce GI upset. |
| Patient Advice | Take this medication exactly as prescribed, even if you feel better. · Complete the full course of therapy to prevent resistance. · Notify your doctor if you have a penicillin allergy. · Take with food or milk if stomach upset occurs. · Report any signs of allergic reaction (rash, itching, swelling, difficulty breathing) immediately. · If you miss a dose, take it as soon as you remember; skip if almost time for next dose. Do not double dose. · Store at room temperature away from moisture and heat. · May cause diarrhea; contact your doctor if severe or bloody. |