Norfloxacin Milk

Norfloxacin ELISA 4.0 g kg 1 Bovine milk Ovine kidney [77]... 

Lactation It is not known whether ciprofloxacin, norfloxacin, or ofloxacin appears in breast milk following ophthalmic use. Exercise caution when administering ciprofloxacin to a nursing mother. 

Milk and dairy foods decrease the absorption of some tetracyclines (doxycycline and minocycline are not affected), some quinolone antibiotics (absorption of ciprofloxacin and norfloxacin is decreased but ofloxacin is not affected), penicillamine and alendronate. Large volumes of milk can reduce the ulcer-healing properties of bismuth tripotassium dicitratobismuthate (bismuth chelate),... 

ABSORPTION, FATE, AND EXCRETION The quinolones are weU absorbed after oral administration and are widely distributed. Peak serum levels of the fluoroquinolones occur within 1-3 hours of an oral dose of 400 mg. Relatively low serum levels are reached with norfloxacin and limit its usefulness to the treatment of urinary tract infections. Food does not impair oral absorption but may delay the time to peak serum concentrations. Oral doses in adults are 200-400 mg every 12 hours for ofloxacin, 400 mg every 12 hours for norfloxacin and pefloxacin, and 250-750 mg every 12 hours for ciprofloxacin. Bioavailabrlity of the fluoroquinolones exceeds 50% for all agents and 95% for several. The serum half-lives range from 3 to 5 hours for norfloxacin and ciprofloxacin to 20 hours for sparfloxacin. The volume of distribution of quinolones is high, with concentrations in urine, kidney, lung and prostate tissue, stool, bUe, and macrophages and neutrophils higher than serum levels. Quinolone concentrations in CSF, bone, and prostatic fluid are lower than in serum. Pefloxacin and ofloxacin levels in ascites fluid approach serum levels, and ciprofloxacin, ofloxacin, and pefloxacin have been detected in human breast milk. 

A study found that 300 mL of milk or yoghurt reduced the absorption and the peak plasma levels of a single 200-mg dose of norfloxacin by roughly... 

The proposed reason for these changes is that the calcium in milk and yoghurt or other dairy products combines with the ciprofloxacin and norfloxacin to produce insoluble chelates. Compare also Quinolones -i-Antacids or Calcium compounds , p.328. 

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