Bioequivalence study of two oral amoxicillin formulations (Biocillin® and Atcomox 87%®) in broiler chickens

Mohamed Aboubakr, Mohamed Elbadawy


Background: The present study was designed to assess the comparative bioequivalence of Biocillin® and Atcomox87%® in healthy broiler chickens after oral administration of both products in a dose of 20 mg amoxicillin base/kg.b.wt.

Methods: Twenty-four broiler chickens were divided into two groups. The first group was designed to study the pharmacokinetics of Biocillin®, while the 2nd group was designed to study the pharmacokinetics of Atcomox87%®. Each broiler chicken in both groups was injected intravenously with 20 mg amoxicillin pure standard/kg.b.wt. After 15 days both groups taken orally Biocillin® and Atcomox87%®, respectively. Blood samples were obtained from the wing vein and collected immediately before and at 0.08, 0.16, 0.25, 0.5, 1, 2, 4, 8, 12 and 24 hours after a single intravenous or oral administration.

Results: Amoxicillin in both products obeyed a two compartments open model following I.V. injection. The disposition kinetics of Biocillin® and Atcomox87%® following oral administration of 20 mg amoxicillin base/kg.b.wt. revealed that the maximum blood concentration [Cmax] were 10.79 and 10.30 μg/ml and attained at [tmax] of 0.90 and 0.86 hours, respectively. The mean systemic bioavailability of amoxicillin in Biocillin® and Atcomox 87%® after oral administration in healthy chickens was 64.15 and 65.54%, respectively.

Conclusions: Atcomox 87%® is bioequivalent to Biocillin® since the ratios of Cmax, AUC0-24 and AUC0-∞ (T/R) were 0.95, 0.91 and 0.90 respectively. These are within the bioequivalence acceptance range. Biocillin® and Atcomox87%® are therefore bioequivalent and interchangeable.


Amoxicillin, Bioequivalence, Chickens

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