CEFADROXIL

Cefadroxil monohydrate, USP is a semisynthetic cephalosporin antibiotic intended for oral administration. It is a white to yellowish-white crystalline powder. It is soluble in water and it is acid-stable. It is chemically designated as 5-Thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, 7-[[amino(4-hydroxyphenyl)acetyl]amino]-3-methyl-8-oxo-, monohydrate, [6R-[6α,7β(R*)]]-. It has the formula C 16 H 17 N 3 O 5 S · H 2 O and the molecular weight of 381.40. It has the following structural formula: Cefadroxil for oral suspension USP, after reconstitution, contains cefadroxil monohydrate equivalent to 250 mg or 500 mg cefadroxil base per 5 mL. In addition, cefadroxil for oral suspension also contains the following inactive ingredients: FD&C Yellow No. 6 Aluminum lake, polysorbate 80, sodium benzoate, sucrose, xanthan gum, orange flavor and pineapple flavor. The orange flavor and pineapple flavor contains sulfur dioxide. Chemical Structure

Cefadroxil is indicated for the treatment of patients with infection caused by susceptible strains of the designated organisms in the following diseases: Urinary tract infections caused by E. coli, P. mirabilis, and Klebsiella species. Skin and skin structure infections caused by staphylococci and/or streptococci. Pharyngitis and/or tonsillitis caused by Streptococcus pyogenes (Group A beta-hemolytic streptococci). Note: Only penicillin by the intramuscular route of administration has been shown to be effective in the prophylaxis of rheumatic fever. Cefadroxil is generally effective in the eradication of streptococci from the oropharynx. However, data establishing the efficacy of cefadroxil for the prophylaxis of subsequent rheumatic fever are not available. Note: Culture and susceptibility tests should be initiated prior to and during therapy. Renal function studies should be performed when indicated. To reduce the development of drug-resistant bacteria and maintain the effectiveness of cefadroxil and other antibacterial drugs, cefadroxil should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemology and susceptibility patterns may contribute to the empiric selection of therapy.

Cefadroxil is acid-stable and may be administered orally without regard to meals. Administration with food may be helpful in diminishing potential gastrointestinal complaints occasionally associated with oral cephalosporin therapy. Adults Urinary Tract Infections: For uncomplicated lower urinary tract infections (i.e., cystitis) the usual dosage is 1 or 2 g per day in a single (q.d.) or divided doses (b.i.d.). For all other urinary tract infections the usual dosage is 2 g per day in divided doses (b.i.d.). Skin and Skin Structure Infections: For skin and skin structure infections the usual dosage is 1 g per day in single (q.d.) or divided doses (b.i.d.). Pharyngitis and Tonsillitis: Treatment of group A beta-hemolytic streptococcal pharyngitis and tonsillitis—1 g per day in single (q.d.) or divided doses (b.i.d.) for 10 days. Children For urinary tract infections, the recommended daily dosage for children is 30 mg/kg/day in divided doses every 12 hours. For pharyngitis, tonsillitis, and impetigo, the recommended daily dosage for children is 30 mg/kg/day in a single dose or in equally divided doses every 12 hours. For other skin and skin structure infections, the recommended daily dosage is 30 mg/kg/day in equally divided doses every 12 hours. In the treatment of beta-hemolytic streptococcal infections, a therapeutic dosage of cefadroxil should be administered for at least 10 days. See chart for total daily dosage for children. DAILY DOSAGE OF CEFADROXIL SUSPENSION Child’s Weight Ibs kg 250 mg/5 mL 500 mg/5 mL 10 4.5 ½ tsp 20 9.1 1 tsp 30 13.6 1½ tsp 40 18.2 2 tsp 1 tsp 50 22.7 2½ tsp 1¼ tsp 60 27.3 3 tsp 1½ tsp 70 & above 31.8+ — 2 tsp Renal Impairment In patients with renal impairment, the dosage of cefadroxil monohydrate should be adjusted according to creatinine clearance rates to prevent drug accumulation. The following schedule is suggested. In adults, the initial dose is 1000 mg of cefadroxil and the maintenance dose (based on the creatinine clearance rate [mL/min/1.73 m 2 ]) is 500 mg at the time intervals listed below. Creatinine Clearances Dosage Interval 0 to 10 mL/min 36 hours 10 to 25 mL/min 24 hours 25 to 50 mL/min 12 hours Patients with creatinine clearance rates over 50 mL/min may be treated as if they were patients having normal renal function. Reconstitution Directions for Oral Suspension Bottle Size Reconstitution Directions 100 mL Suspend in a total of 60 mL water. Method: Tap bottle lightly to loosen powder. Add 60 mL of water in two portions. Shake well after each addition. 75 mL Suspend in a total of 45 mL water. Method: Tap bottle lightly to loosen powder. Add 45 mL of water in two portions. Shake well after each addition. 50 mL Suspend in a total of 30 mL water. Method: Tap bottle lightly to loosen powder. Add 30 mL of water in two portions. Shake well after each addition. After reconstitution, store in refrigerator. Shake well before using. Keep container tightly closed. Discard unused portion after 14 days.

Cefadroxil is contraindicated in patients with known allergy to the cephalosporin group of antibiotics.

Gastrointestinal Onset of pseudomembranous colitis symptoms may occur during or after antibiotic treatment (see WARNINGS ). Dyspepsia, nausea and vomiting have been reported rarely. Diarrhea has also occurred. Hypersensitivity Allergies (in the form of rash, urticaria, angioedema, and pruritus) have been observed. These reactions usually subsided upon discontinuation of the drug. Anaphylaxis has also been reported. Other Other reactions have included hepatic dysfunction including cholestasis and elevations in serum transaminase, genital pruritus, genital moniliasis, vaginitis, moderate transient neutropenia, fever. Agranulocytosis, thrombocytopenia, idiosyncratic hepatic failure, erythema multiforme, Stevens-Johnson syndrome, serum sickness, and arthralgia have been rarely reported. In addition to the adverse reactions listed above which have been observed in patients treated with cefadroxil, the following adverse reactions and altered laboratory tests have been reported for cephalosporin-class antibiotics: Toxic epidermal necrolysis, abdominal pain, superinfection, renal dysfunction, toxic nephropathy, aplastic anemia, hemolytic anemia, hemorrhage, prolonged prothrombin time, positive Coombs’ test, increased BUN, increased creatinine, elevated alkaline phosphatase, elevated aspartate aminotransferase (AST), elevated alanine aminotransferase (ALT), elevated bilirubin, elevated LDH, eosinophilia, pancytopenia, neutropenia. Several cephalosporins have been implicated in triggering seizures, particularly in patients with renal impairment, when the dosage was not reduced (see DOSAGE AND ADMINISTRATION and OVERDOSAGE ). If seizures associated with drug therapy occur, the drug should be discontinued. Anticonvulsant therapy can be given if clinically indicated.