Cefadroxil: what the FDA reviewed for dog products
1 Freedom of Information summary from the FDA Center for Veterinary Medicine for products containing Cefadroxil, as typed records: every value below is followed by the verbatim passage it was taken from. Species as stated by each summary: Dogs; Cats.
Products
- Cefa-Drops® (NADA/ANADA 140-684)
Cefa-Drops® NADA 140-684, Original approval, July 20, 1988; sponsor HQ Specialty Pharma Corp.; species: Dogs; Cats; foi_id 1728; FDA PDF
Indication
Dogs: genitourinary tract infections (cystitis) caused by susceptible E. coli, Proteus mirabilis and Staphylococcus aureus; skin and soft tissue infections (cellulitis, pyoderma, dermatitis, wound infections, abscesses) caused by susceptible S. aureus. (Cats: skin and soft tissue infections.)
Dose regimen
10 mg/lb, Oral (powder for oral suspension, 50 mg/ml when reconstituted), twice daily (dogs); once daily (cats)
Dogs: 10 mg/lb twice daily Cats: 10 mg/lb once daily
Pharmacokinetics
| Parameter | Value | Conditions | Quote |
|---|---|---|---|
| auc | 4900.4 (tablets) vs 4699.3 (liquid) (mcg x min)/ml | dogs, 10 mg/lb oral, crossover, average n=12; pivotal bioequivalency study; columns = tablets, liquid | DOG area under curve (mcg x min)/ml 4900.4 4699.3 |
| tmax | 125.8 min (tablets) vs 87.1 min (liquid) | dogs, 10 mg/lb oral, crossover, average n=12; columns = tablets, liquid | DOG time to peak concentration (min) 125.8 87.1 |
| cmax | 19.8 mcg/ml (tablets) vs 22.0 mcg/ml (liquid) | dogs, 10 mg/lb oral, crossover, average n=12; columns = tablets, liquid | DOG peak concentration (mcg/ml) 19.8 22.0 |
| other | absorption rate constant .0308 (tablets) vs .0393 (liquid) min -1 | dogs, 10 mg/lb oral, crossover, average n=12; columns = tablets, liquid | DOG absorption rate constant (min -1) .0308 .0393 |
| other | elimination rate constant .0052 (tablets) vs .0055 (liquid) min -1 | dogs, 10 mg/lb oral, crossover, average n=12; columns = tablets, liquid | DOG elimination rate constant (min -1) .0052 .0055 |
| protein binding | 25% | corroborative bioavailability study, six hound-type dogs, 22 mg/kg; serum protein binding | Protein binding averaged 25%. |
| other | 39% of intravenous dose recovered in urine within 24 hours | corroborative bioavailability study, six hound-type dogs, intravenous 22 mg/kg | Results of urinary recovery studies revealed that an average of 39% of the intravenous dose of cefadroxil was recovered within 24 hours from the dogs. |
| auc | 2940 (tablets), 4248 (suspension), 3768 (capsules) mcg x min/ml | corroborative bioavailability study, six hound-type dogs, 22 mg/kg (10 mg/lb) oral; columns = tablets, suspension, capsules | area under curve (mcg x min/ml) 2940 4248 3768 |
Effectiveness
Pivotal multi-site clinical field study (11 practices) comparing cefadroxil oral suspension vs approved cefadroxil tablets (active control) at 10 mg/lb twice daily in dogs (once daily in cats) for skin/soft tissue infections and canine cystitis; no statistical analysis deemed necessary; n = 45 dogs (22 liquid, 23 tablets) of 144 evaluable animals; primary endpoint: pre/post treatment physical exam, bacteriologic culture (and urinalysis/culture by cystocentesis for cystitis); investigator overall evaluation excellent/good/fair/poor; result: Both formulations effective; dog skin infections excellent/good 17/18 (94%) liquid vs 17/18 (94%) tablet; dog urinary infections 4/4 (100%) liquid vs 3/5 (60%) tablet; all organisms eliminated 94% (liquid) vs 97% (tablet)
A total of 148 animals were entered into the study of which 144 were evaluable, comprised of 99 cats and 45 dogs. Of the 99 cats, 55 were treated with the cefadroxil liquid formulation and 44 with approved cefadroxil tablets. Of the 45 dogs, 22 were treated with the liquid and 23 received the tablet formulation. All of the cats and 36 of the dogs were treated for skin and soft tissue infections, while the remaining nine dogs were treated for urinary tract infections.
Adverse reactions
| Term | Treated | Control | Quote |
|---|---|---|---|
| side effects in dogs (field study) | none reported | No side effects were reported in dogs. | |
| diarrhea (cats, field study) | one cat (liquid) | two cats (tablets) | Diarrhea was reported in one cat treated with liquid and two cats treated with tablets. |
| vomiting (cats, field study) | one cat | one cat | Vomiting was reported in one cat in each group and lethargy was noted in one cat of the tablet group. |
Extraction notes: 1988 NADA for a new dosage form (powder for oral suspension) of cefadroxil; summary has no Species/Class field but gives dog and cat dosage/indications, so species_class lists both. Effectiveness and safety rely on prior tablet approval NADA 119-688 plus bioequivalency and field data; no new target animal safety study ('The safety of cefadroxil has been demonstrated and approved (NADA 119-688) using the tablet formulation'). Field study result rows as extracted: 'Dog, skin infections 17/18 (94%) 17/18 (94%)' and 'Dog, urinary infections 4/4 (100%) 3/5 (60%)' (columns LIQUID, TABLET). PK table columns: AVERAGE (n=12) TABLETS, AVERAGE (n=12) LIQUID; the concentration-time figure was lost in extraction.
Reproduce: foi_structured_search(query="Cefadroxil") and foi_summary_get(foi_id=...) in dog-geroscience-mcp; dataset foi-summaries-dog (config structured).