Tetracycline Orange juice

Colestipol 30 g taken either in 180 mL of water or orange juice reduced the absorption of a single 500-mg dose of oral tetracycline in 9 healthy subjects by 54 to 56%, as measured by reeovery in the urine. ... 

Friedman H, Greenblatt DJ, LeDuo BW. Impaired absorption of tetracycline by colestipol is not reversed by orange juice. / CIi Plrarmacol (1989) 29, 748-51. 

The calcium in food can complex with tetracycline to reduce its absorption. This is particularly notable with dairy products, which can reduce the absorption of the tetracyclines by up to 80%, thereby reducing or even abolishing their therapeutic effects. Doxyeyeline and minocycline are less affected by daily products (25 to 30% reduction). Orange juice and coffee do not interact with tetracycline. 

A study in 9 healthy subjects found that 200 mL of orange juice or coffee (milk content, if any, unstated) did not significantly affect the bioavailability of a single 250-mg dose of tetracycline. This is despite the fact that orange juice contains 35 to 70 mg calcium per 100 mL. ... 

Orange juice appears not to interact, despite its calcium content, because at the relevant pH values in the gut, the calcium is bound to components within the orange juice (citric, tartaric and ascorbic acids) and is not free to combine with the tetracycline. ... 

Jung H, Rivera O, Reguero MT, Rodriguez IM, Moreno-Espai R. Influence of liquids (coffee and orange juice) on the bioavailability of tetracycline. Bi< harm Drug Dispos (1990) 11, 729-34. 

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