Fluconazole Dosing For 'Intestinal Candida'

In our latest question and answer, the pharmacist discusses fluconazole dosing for gastrointestinal problems.


Does fluconazole prescribed for an intestinal Candida infection require a loading dose?

Asked by Susie On Dec 08, 2022

Answered by
Medical Content Reviewed By HelloPharmacist Staff

Published Dec 08, 2022
Last updated Jun 14, 2024

Key points

  • An 'intestinal candida' infection could be referring to many different things. Candida, a type of yeast, is part of your normal gastrointestinal flora, and its presence does not indicate an infection that needs treatment.
  • Some studies suggest that an overgrowth of Candida can cause gastrointestinal symptoms in those with existing inflammatory conditions, like ulcerative colitis. Treatment with fluconazole can sometimes help relieve certain symptoms (e.g., diarrhea) if they are getting worse.
  • Some providers may also suspect that an overgrowth of Candida causes 'leaky gut syndrome', a condition that is not currently recognized as a medical diagnosis but is nevertheless sometimes treated.
  • An 'intestinal candida' infection could be referring to peritonitis (inflammation of the lining of your abdomen) or an 'intra-abdominal' infection, which does typically require treatment. If fluconazole is used, a loading dose is generally required.


I'm not exactly sure what you mean by an 'intestinal candida' infection. Candida species, a type of yeast, are part of your normal gastrointestinal flora. If you had a stool culture done, and a Candida species was shown to be present, that does not represent an infection and generally would not warrant any treatment.

Nevertheless, I certainly don't want to discount what some more recent studies suggest the symptoms of a suspected 'overgrowth' of Candida can cause.

Studies suggest that an 'overgrowth' of candida can occur in certain individuals with inflammatory conditions, like ulcerative colitis and Crohn's disease, which can cause worsening symptoms of diarrhea, gas, bloating, or nausea. It is theorized that Candida can delay healing and exacerbate diseases for these individuals, and thus, treating an overgrowth with an antifungal could provide beneficial effects for them.

Additionally, although not recognized as a medical diagnosis, some providers, typically on the more holistic end of things, believe that an overgrowth of Candida in the gastrointestinal tract can cause 'leaky guy syndrome', which can also cause some of the symptoms I've described above (e.g., bloating, diarrhea).

It is important to point out here too that an 'intestinal candida' infection could be a layman's way of describing the very real problem of a Candida species causing an infection following a gastrointestinal tract perforation (i.e., tear). This is typically referred to as peritonitis or an 'intra-abdominal' infection.

Dosing Considerations

Since I don't know exactly what you are treating with fluconazole, it's tough to give you what the recommended dosages are. I also don't know if you are referring to an oral dosage or an intravenous one.

However, we can start with an FDA-approved indication. Clinical studies support the following dosing an intra-abdominal infection (i.e. peritonitis) caused by Candida:

  • Adults [oral tablet]: Fluconazole 800 mg by mouth once, then 400 mg by mouth once daily for at least two weeks or longer depending on when the signs and symptoms of peritonitis are resolved.
  • Adults [intravenous]: Fluconazole 800 mg intravenously, then 400 mg intravenously once daily for at least two weeks or longer depending on when the signs and symptoms of peritonitis are resolved.

As I mentioned in the section above, Candida being identified as simply being present in your gastrointestinal tract generally does not warrant treatment, and there is no recommended dosing of fluconazole for gastrointestinal overgrowth or for 'leaky gut'.

However, some studies suggest that if Candida is suspected of causing significant gastrointestinal symptoms (such as nausea, diarrhea, bloating, etc...) due to overgrowth in those with pre-existing inflammatory conditions (like ulcerative colitis), or in those with 'leaky gut', dosages of fluconazole are similar to those used in the treatment of conditions like oral thrush or a urinary tract infection, which is:

  • Adults [oral tablet]: Fluconazole 100 to 200 mg by mouth once daily for 7 to 14 days. No loading dose is required.

Final Words

I hope this answer helped! If you want to write back with some more details of what you are treating, and some background on why your provider is suggesting fluconazole, I can likely give a more detailed answer.

Thanks for reaching out!


  • Clinical Practice Guideline for the Management of Candidiasis: 2016 Update by the Infectious Diseases Society of America, PubMed
  • Inflammation and gastrointestinal Candida colonization, PubMed
  • Gut microbiota dysbiosis in functional gastrointestinal disorders: Underpinning the symptoms and pathophysiology, PubMed
  • Review article: fungal alterations in inflammatory bowel diseases, PubMed
  • Fungal infections in patients with inflammatory bowel disease: A systematic review, PubMed

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