From the Guidelines
Fluconazole can cause diarrhea as a side effect in some patients, and it is essential to manage this symptom to prevent morbidity and mortality. This antifungal medication, commonly used to treat yeast infections like candidiasis, may disrupt the normal gut flora leading to gastrointestinal disturbances. If you experience diarrhea while taking fluconazole, it's typically mild and resolves on its own after completing treatment. For standard oral candidiasis, fluconazole is usually prescribed as a single 150mg dose, while more severe or systemic infections may require 100-400mg daily for 1-4 weeks, as recommended by the Infectious Diseases Society of America in their 2016 update 1. To minimize gastrointestinal effects, take fluconazole with food and stay hydrated. Some key points to consider when taking fluconazole include:
- The medication can be taken with or without food, as absorption is not affected by food consumption, gastric pH, or disease state 1.
- Fluconazole achieves urine concentrations that are 10–20 times the concentrations in serum, making it an effective treatment option for urinary tract infections 1.
- The recommended dosing regimen for patients with invasive candidiasis is an average loading dose of 800 mg (12 mg/kg), followed by an average daily dose of 400 mg (6 mg/kg) 1. If diarrhea becomes severe, bloody, or persists beyond treatment, contact your healthcare provider immediately as this could indicate a more serious reaction or a different condition like Clostridioides difficile infection. Probiotics may help restore gut flora balance during treatment, though you should discuss this with your doctor first, as suggested by the clinical practice guidelines for the management of candidiasis 1. Fluconazole causes diarrhea because it can affect beneficial fungi in the gut alongside the pathogenic ones it targets, temporarily disrupting the intestinal microbiome. It is crucial to weigh the benefits and risks of fluconazole treatment and consider alternative therapies, such as itraconazole or voriconazole, in patients who experience severe gastrointestinal side effects, as recommended by the clinical practice guidelines for the management of candidiasis 1.
From the FDA Drug Label
In Patients Receiving a Single Dose for Vaginal Candidiasis: ... Other side effects reported with an incidence equal to or greater than 1% included diarrhea (3%), In Patients Receiving Multiple Doses for Other Infections: ... The following treatment-related clinical adverse events occurred at an incidence of 1% or greater in 4048 patients receiving fluconazole for 7 or more days in clinical trials: ... diarrhea 1.5%. The most common side effects of fluconazole tablets include: ... diarrhea ...
Diarrhea is a possible side effect of fluconazole, with an incidence of 3% in patients receiving a single dose for vaginal candidiasis, 1.5% in patients receiving multiple doses for other infections, and is listed as one of the most common side effects of fluconazole tablets 2, 2.
From the Research
Fluconazole and Diarrhea
- There is no direct evidence in the provided studies that links fluconazole to diarrhea as a side effect.
- The study 3 mentions that fluconazole was reasonably well tolerated, with raised concentrations of liver enzymes observed in 14 patients, and other adverse effects such as fatigue, nausea, gastric pain, sleepiness, and epileptic seizure.
- The study 4 does not mention diarrhea as a side effect of fluconazole.
- The studies 5, 6, and 7 do not provide information on the side effects of fluconazole related to diarrhea.
- It can be noted that none of the provided studies specifically investigate the relationship between fluconazole and diarrhea, therefore, there is limited evidence to assist in answering this question.