Abstract

Background: The aim of the present study was to determine pharmacokinetic interaction of ceftriaxone and polyherbal drug (Fibrosin^®) in lactating goats following single dose intramammary administration of ceftriaxone with 1 h pre-single dose oral administration of Fibrosin^®.

Methods: Pharmacokinetic interaction of ceftriaxone and Fibrosin^® was evaluated in lactating goats following single dose intramammary administration of ceftriaxone at 50 mg/kg with 1 h pre-single dose oral administration of Fibrosin^® (1.9 g). Estimation of ceftriaxone and its metabolite, ceftizoxime, was determined by high performance liquid chromatography.

Results: Fibrosin^® treated goats showed a typical absorption-reabsorption phase of ceftriaxone in plasma following intramammary administration. Neither ceftriaxone nor ceftizoxime was detected in the plasma and urine of goats without Fibrosin^® treatment, however, ceftriaxone persisted for 36 h and ceftizoxime was present from 48 h to 72 h in the plasma of Fibrosin^® treated goats. Ceftizoxime was also available from 72 h to 360 h post-dosing in milk in the presence of Fibrosin^® following intramammary administration of ceftriaxone suggesting the polyherbal drug played a major role in the penetration of ceftriaxone from milk to systemic circulation. Furthermore, the polyherbal drug increased the bioavailability of ceftizoxime in milk following the metabolism of ceftriaxone.

Conclusions: Polyherbal drug (Fibrosin^®) plays a major role in the penetration of ceftriaxone from milk to systemic circulation and may be responsible for increased bioavailability of its metabolite in the mammary gland resulting in higher concentration and longer persistence of the drug in milk.