Fluconazole dosing

Varhe A, Olkkola KT, Neuvonen PJ. Effect of fluconazole dose on the extent of fluconazole-triazolam interaction. Br J Clin Pharmacol 1996 42(4) 465-70. 

If the creatinine clearance is below 40 ml/minute fluconazole doses should be adjusted (SED-12, 682) (7). 

The interaction between rifampicin and fluconazole appears to be established and of clinical importance. Although rifampicin has only a modest effect on fluconazole, the cases of relapse cited above and the need for an increased dosage indicate that this interaction can be clinically important. Monitor concurrent use and increase the fluconazole dosage if necessary. One study suggests a 30% increase in fluconazole dose may be considered for serious infections during concurrent rifampicin therapy. This may be especially important during prophylaxis of cryptococcal meningitis with lower doses of fluconazole, such as 200 mg daily. ... 

A brief report noted that 3 of 9 patients taking fluconazole and phenytoin required an increase in fluconazole dose or the substitution of another antifungal due to a lack of efficacy. It was suggested that phenytoin may reduce fluconazole levels in some patients. However, in the controlled studies cited above, fluconazole serum levels were unaltered by phenytoin. 

Fluconazole. Eight healthy subjects were given fluconazole or a placebo daily for 4 days, with a single 250-microgram oral dose of triazolam on day 4. The AUC of triazolam was increased by 1.6-fold, 2.1 -fold, and 4.4-fold by 50,100, and 200 mg fluconazole, respectively, and the maximum plasma triazolam levels were more than doubled by the 200-mg fluconazole dose. The 100- and 200-mg fluconazole doses both produced significant changes in the psychomotor tests of triazolam, but the 50-mg dose did not. ... 

Usually the frequency of administration is similar to that of adults. However, this does sometimes require amendment. E.g. fluconazole dosing frequency varies with age, due to the changes in elimination. 

At the tested daily dose of 50 mg, fluconazole appears to be slightly less active against dermatophytes. The substance is used mainly to treat vaginal candidosis (a single capsule of 150 mg) and oral and esophageal candidosis (50 mg od for 14 d). In a number of countries, ie, England, the maximal period of treatment is 14 d. 

Toxicological studies have demonstrated that there are no important problems with fluconazole. Therapeutic doses of fluconazole may cause enzyme induction in the Hver. This suggests that interactions with other dmgs cannot be excluded. The side effects are similar to those of itraconazole and include nausea, headache, and vertigo. Occasionally, increased Hver enzymes may be noted. Like itraconazole, fluconazole is contraindicated during pregnancy. 

The primary care provider has prescribed fluconazole 200 mg PO initially, followed by 100 mg PO daily. On hand are fluconazole 100-mg tablets. What would tiie nurse administer as tiie initial dose ... 

Treatment fluconazole, itraconazole, ketoconazole, Amphotericin B Consider liposomal products decrease or stop CSA or TAC to minimize nephrotoxicity Remember to adjust doses of renally eliminated drugs (e.g., acyclovir, ganciclovir, TMP-SMX)... 

Treatment of fungal IE is exceptionally difficult. There is a significant lack of studies to identify and recommend the most appropriate therapy. Currently, amphotericin B is the most common treatment. However, valve replacement surgery is often considered an adjunct therapy. Intravenous antifungal therapy requires high doses for a minimum of 8 weeks of treatment. Oral azoles (e.g., fluconazole) are used as long-term suppressive therapy to prevent relapse. The exact role of some... 

Fluconazole 1 50 mg, one tablet orally as a single dose Tioconazole 6.5% ointment, 5 g intravaginally as a single application... 

The goal of treating recurrent WC is control of the infection, rather than cure. First, any acute episodes are treated, followed by maintenance therapy. For the treatment of acute episodes, intravaginal or oral azoles can be utilized. Although acute episodes of recurrent WC will respond to azole therapy, some patients may require prolonged therapy in order to achieve remission. To achieve remission, a second dose of oral fluconazole 150 mg repeated 3 days after the first dose or 14 days of topical azole therapy can be used. The practitioner should consider that non-albicans infections are more common in recurrent WC therefore fluconazole and itraconazole resistance may make these agents less effective. 

Two to three weeks of fluconazole or itraconazole solution are highly effective and demonstrate similar clinical response rates.32 Doses of 100 to 200 mg are effective in immunocompetent patients but doses up to 400 mg are recommended for immunocompromised patients. Due to variable absorption, ketoconazole and itraconazole capsules should be considered second-line therapy. In severe cases, oral azoles may prove ineffective, warranting the use of amphotericin B for 10 days. Although echinocandins and voriconazole are effective in treatment of esophageal candidiasis, experience remains limited. 

Diffuse pneumonia or AM-B 1 -1.5 mg/kg per day with dose and however, fluconazole is better tolerated than... 

Itraconazole and ketoconazole (200-800 mg/day orally for 1 year) are effective in 74% to 86% of cases, but relapses are common fluconazole 200-400 mg daily is less effective (64%) than ketoconazole or itraconazole, and relapses are seen in 29% of responders Severe disease Amphotericin B 0.7 mg/kg/day for a minimum total dose of 35 mj kg is effective in 59% to 100% of cases and should be used in patients who require hospitalization or are unable to take itraconazole because of drug interactions, allergies, failure to absorb drug or failure to improve clinically after a minimum of 12 weeks of itiaconazole therapy... 

Patients with disease outside the lungs should be treated with 400 mg/day of an oral azole. For meningeal disease, fluconazole 400 mg/day orally should be used however, some clinicians initiate therapy with 800 mg or 1,000 mg/day and itraconazole doses of 400 to 600 mg/day are comparable. 

Isolated pulmonary disease (without evidence of CNS infection) Asymptomatic disease Drug therapy generally not required observe carefully or fluconazole 400 mg orally daily x 3-6 months Mild to moderate symptoms Fluconazole 200-400 mg orally daily x 3-6 months severe disease or inability to take azoles amphotericin B 0.4-0.7 mg/kg/day (total dose of 1-2 g)... 

For patients receiving weak CYP3A4 inhibitors (eg, erythromycin, saquinavir, verapamil, fluconazole), reduce the starting dose to 25 mg once daily. 

Multiple dose The daily dose of fluconazole is the same for oral and IV administration. In general, a loading dose of twice the daily dose is recommended on the first day of therapy to result in plasma levels close to steady state by the second day of therapy. 

Metaboiism/Excretion - Fluconazole is cleared primarily by renal excretion, with approximately 80% of the dose appearing in the urine unchanged, approximately 11% as metabolites. The dose may need to be reduced in patients with impaired renal function. A 3-hour hemodialysis session decreases plasma concentrations by approximately 50%. 

Oropharyngeal candidiasis - 200 mg/day for 1 to 2 weeks. Vigorously swish the solution in the mouth (10 ml at a time) for several seconds and swallow. For patients with oropharyngeal candidiasis unresponsive/refractory to treatment with fluconazole tablets, the recommended dose of itraconazole is 100 mg twice daily. Expect clinical response in 2 to 4 weeks. Patients may be expected to relapse shortly after discontinuing therapy. Limited data on the safety of long-term use (more than 6 months) of the oral solution are available at this time. 

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