Fluconazole Antacids

AZOLES ANTACIDS i plasma concentration of itraconazole and ketoconazole, with risk of therapeutic failure Itraconazole absorption in capsule form requires an acidic gastric environment and thus absorption would l Separate administration of agents that i gastric acidity by 1-2 hours. However, absorption of itraconazole liquid solution does not require an acidic environment and could be used instead it does not need to be given with food. Fluconazole absorption is not pH dependent, and this is a suitable alternative... 

Fluconazole absorption after oral administration is not influenced by gastric pH thus there is no effect of antacids such as co-magaldrox (SED-12, 682) (73). 

Thorpe JE, Baker N, Bromet-Petit M. Effect of oral antacid administration on the pharmacokinetics of oral fluconazole. Antimicrob Agents Chemother 1990 34(10) 2032-3. 

Drug interactions occur between tipranavir and fluconazole and between tipranavir and clarithromycin, increasing the AUC over a 12 hour period for tipranavir by 56 and 59%, respectively. Care should be taken when administering tipranavir with CYP450 inhibitors and inducers, because clinically significant interactions are possible. Coadministration of tipranavir with antacids decreases the tripranavir AUC by up to 33%. 

The gastrointestinal absorption of ketoconazole is markedly reduced by antacids. Itraconazole may also be modestly affected. However, the absorption of fluconazole and posaconazole appears not be to significantly affected by antacids. Similarly, voriconazole is not expected to be affected. 

Antacids do not significantly affect posaconazole or fluconazole levels, and, based on the data with H2-receptor antagonists , (p.217), would not be expected to affect voriconazole levels. 

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