Foods Fluconazole

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... 

Like fluconazole, voriconazole (Muijsers et al., 2002) is polar, with moderate aqueous solubility (0.5 mg/mL), resulting in rapid absorption (maximum concentration achieved in less than 2 h) and oral bioavailability (96%). Moderate food effects have been observed. Distribution is wide with a steady-state volume of 4.6L/kg and moderate binding to plasma proteins (58%). 

Although itraconazole and fluconazole are both triazoles, they are chemically and pharmacologically distinct. Itraconazole (Sporanox) is lipophilic and water insoluble and requires a low gastric pH for absorption. Oral bioavailability is variable, only 50 to 60% when taken with food and 20% or less when the drug is taken on an empty stomach. Itraconazole is highly protein bound (99%) and is metabolized in the liver and excreted into the bile. With initial dosing, the plasma half-life is 15 to 20 hours steady-state serum concentrations are reached only after 2 weeks of therapy, when the half-life is extended to 30 to 35 hours. In lipophilic tissues, drug concentration is 2 to 20 times that found in... 

Fluconazole is well absorbed following oral administration, with a plasma half-life of 30 hours. In view of this long half-life, daily doses of 100 mg are sufficient to treat mucocutaneous candidiasis alternate-day doses are sufficient for dermatophyte infections. The plasma half-life of itraconazole is similar to that of fluconazole, and detectable therapeutic concentrations remain in the stratum corneum for up to 28 days following termination of therapy. Itraconazole is effective for the treatment of onychomycosis in a dosage of 200 mg daily taken with food to ensure maximum absorption for 3 consecutive months. Recent reports of heart failure in patients receiving itraconazole for onychomycosis have resulted in recommendations that it not be given for treatment of onychomycosis in patients with ventricular dysfunction. 

The oral bioavailability of fluconazole, following administration of cither tablet or oral. suspension do.sagc forms, is excellent. Apparently, the presence of two weakly basic triazole rings in the molecule confers sufficient aqueous solubility to balance the lipophilicity of the 2.4-difluorophenyl group. The oral absorption of fluconazole, in contrast to the oral absorption of ketoconazolc or itraconazole, is not affected by alteration in ga.strointcstinal acidity or the presence of food. 

ABSORPTION, DISTRIBUTION, AND EXCRETION Fluconazole is almost completely absorbed from the G1 tract irrespective of food or gastric acidity. Only 10% of drug in circulation is protein bound. Renal excretion accounts for >90% of elimination, with a of 25 hours. Fluconazole readily diffuses into body fluids, including breast milk, sputum, saliva, and CSF. The dosage interval should be increased from 24-48 hours for a creatinine clearance of 21 0 mL/min and to 72 hours at 10-20 mL/min. In renal failure, a dose of 100-200 mg is given after hemodialysis. 

Itraconazole capsules should be taken with or after food to improve absorption, whereas itraconazoie soiution shouid be taken at ieast one hour before food. Food increases the absorption of posaconazoie suspension, and this shouid be taken with a meat or nutritionat supptement. Some manufacturers advise taking keto-conazoie with food, but two studies have shown iittie effect of food on absorption, and one actuatty showed a decrease. The bioavail-abitity of voriconazote is modestty reduced by food, and the manufacturer recommends it be taken at least one hour before or after a meal. Food does not appear to affect the bioavailability of fluconazole capsules. 

A study in 12 healthy subjects found that food had no therapeutically relevant effect on the pharmacokinetics of a single 100-mg dose of fluconazole in capsule form. ... 

There appears to be no relevant interaction between food and fluconazole capsules. 

Zimmermann T, Yeates RA, Laufen H, Ffaff G, Wildfeuer A. Influence of conccxnitant food intake on the oml absorption of two triazole antifui al agents, itraconazole and fluconazole. EurJCUn Pharmacol 99A)A6,147-150. 

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