Fluconazole

What it is used for

DIFLUCAN (fluconazole) is indicated for the treatment of:

• 1. Vaginal candidiasis (vaginal yeast infections due to Candida ).
• 2. Oropharyngeal and esophageal candidiasis. In open noncomparative studies of relatively small numbers of patients, DIFLUCAN was also effective for the treatment of Candida urinary tract infections, peritonitis, and systemic Candida infections including candidemia, disseminated candidiasis, and pneumonia.
• 3. Cryptococcal meningitis. Before prescribing DIFLUCAN (fluconazole) for AIDS patients with cryptococcal meningitis, please see CLINICAL STUDIES section. Studies comparing DIFLUCAN to amphotericin B in non-HIV infected patients have not been conducted.

Side effects, and when to stop

DIFLUCAN is generally well tolerated.

In some patients, particularly those with serious underlying diseases such as AIDS and cancer, changes in renal and hematological function test results and hepatic abnormalities have been observed during treatment with fluconazole and comparative agents, but the clinical significance and relationship to treatment is uncertain.

Who should not take it

DIFLUCAN (fluconazole) is contraindicated in patients who have shown hypersensitivity to fluconazole or to any of its excipients. There is no information regarding cross-hypersensitivity between fluconazole and other azole antifungal agents. Caution should be used in prescribing DIFLUCAN to patients with hypersensitivity to other azoles. Coadministration of other drugs known to prolong the QT interval and which are metabolized via the enzyme CYP3A4 such as erythromycin, pimozide, and quinidine are contraindicated in patients receiving fluconazole. (See CLINICAL PHARMACOLOGY: Drug Interaction Studies and PRECAUTIONS.)

Warnings

(1) Hepatic injury: DIFLUCAN should be administered with caution to patients with liver dysfunction. DIFLUCAN has been associated with rare cases of serious hepatic toxicity, including fatalities primarily in patients with serious underlying medical conditions. In cases of DIFLUCAN-associated hepatotoxicity, no obvious relationship to total daily dose, duration of therapy, sex, or age of the patient has been observed. DIFLUCAN hepatotoxicity has usually, but not always, been reversible on discontinuation of therapy. Patients who develop abnormal liver function tests during DIFLUCAN therapy should be monitored for the development of more severe hepatic injury. DIFLUCAN should be discontinued if clinical signs and symptoms consistent with liver disease develop that may be attributable to DIFLUCAN.

(2) Anaphylaxis: In rare cases, anaphylaxis has been reported.

(3) Dermatologic: Exfoliative skin disorders during treatment with DIFLUCAN have been reported. Fatal outcomes have been reported in patients with serious underlying diseases. Patients with deep seated fungal infections who develop rashes during treatment with DIFLUCAN should be monitored closely and the drug discontinued if lesions progress. Fluconazole should be discontinued in patients treated for superficial fungal infection who develop a rash that may be attributed to fluconazole.

(4) Potential for fetal harm: There are no adequate and well-controlled clinical trials of DIFLUCAN in pregnant women. Case reports describe a pattern of distinct congenital anomalies in infants exposed in utero to high dose maternal fluconazole (400 to 800 mg/day) during most or all of the first trimester. These reported anomalies are similar to those seen in animal studies. If DIFLUCAN is used during pregnancy or if the patient becomes pregnant while taking the drug, the patient should be informed of the potential hazard to the fetus. Effective contraceptive measures should be considered in women of child-bearing potential who are being treated with DIFLUCAN 400 to 800 mg/day and should continue throughout the treatment period and for approximately 1 week (5 to 6 half-lives) after the final dose. Epidemiological studies suggest a potential risk of spontaneous abortion and congenital abnormalities in infants whose mothers were treated with 150 mg of fluconazole as a single or repeated dose in the first trimester, but these epidemiological studies have limitations and these findings have not been confirmed in controlled clinical trials. (See PRECAUTIONS: Pregnancy. )

Other medicines and interactions

(See CONTRAINDICATIONS.) Fluconazole is a moderate CYP2C9 and CYP3A4 inhibitor. Fluconazole is also a strong inhibitor of CYP2C19. Patients treated with DIFLUCAN, who are also concomitantly treated with drugs with a narrow therapeutic window metabolized through CYP2C9 and CYP3A4, should be monitored for adverse reactions associated with the concomitantly administered drugs. In addition to the observed /documented interactions mentioned below, there is a risk of increased plasma concentration of other compounds metabolized by CYP2C9, CYP2C19, and CYP3A4 coadministered with fluconazole. Therefore, caution should be exercised when using these combinations and the patients should be carefully monitored. The enzyme inhibiting effect of fluconazole persists 4 to 5 days after discontinuation of fluconazole treatment due to the long half-life of fluconazole. Clinically or potentially significant drug interactions between DIFLUCAN and the following agents/classes have been observed and are described in greater detail below:

Storing it

Store tablets below 30°C (86°F).

DIFLUCAN for Oral Suspension: DIFLUCAN for Oral Suspension is supplied as an orange-flavored powder to provide 35 mL per bottle as follows:

Store dry powder below 30°C (86°F). Store reconstituted suspension between 30°C (86°F) and 5°C (41°F) and discard unused portion after 2 weeks. Protect from freezing.

General

Some azoles, including fluconazole, have been associated with prolongation of the QT interval on the electrocardiogram. Fluconazole causes QT prolongation via the inhibition of Rectifier Potassium Channel current (Ikr). The QT prolongation caused by other medicinal products (such as amiodarone) may be amplified via the inhibition of cytochrome P450 (CYP) 3A4. (See PRECAUTIONS: Drug Interactions. ) During post-marketing surveillance, there have been rare cases of QT prolongation and torsade de pointes in patients taking fluconazole. Most of these reports involved seriously ill patients with multiple confounding risk factors, such as structural heart disease, electrolyte abnormalities, and concomitant medications that may have been contributory. Patients with hypokalemia and advanced cardiac failure are at an increased risk for the occurrence of life-threatening ventricular arrhythmias and torsade de pointes.

Fluconazole should be administered with caution to patients with these potentially proarrhythmic conditions.

Concomitant use of fluconazole and erythromycin has the potential to increase the risk of cardiotoxicity (prolonged QT interval, torsade de pointes) and consequently sudden heart death. This combination should be avoided.

Fluconazole should be administered with caution to patients with renal dysfunction.

Adrenal insufficiency has been reported in patients receiving azoles, including fluconazole. Reversible cases of adrenal insufficiency have been reported in patients receiving fluconazole.

DIFLUCAN Powder for Oral Suspension contains sucrose and should not be used in patients with hereditary fructose, glucose/galactose malabsorption, and sucrase-isomaltase deficiency.

When driving vehicles or operating machines, it should be taken into account that occasionally dizziness or seizures may occur.

There have been reports of cases of superinfection with Candida species other than C. albicans, which are often inherently not susceptible to DIFLUCAN (e.g., Candida krusei ). Such cases may require alternative antifungal therapy (see CLINICAL PHARMACOLOGY, Microbiology ).