Vaginal Yeast Infection: Causes, Symptoms, Diagnosis, and Modern Treatments

Vulvovaginal candidiasis is commonly caused by Candida albicans and appears as vulvar itching, burning, and a thick white discharge. Risk rises with antibiotics, pregnancy, diabetes, and immune suppression. Diagnosis uses exam, microscopy, pH testing, and sometimes culture or molecular tests to distinguish VVC from other vaginal conditions. Treatment for uncomplicated cases includes topical azoles or a single 150 mg oral fluconazole dose in nonpregnant patients; pregnancy and recurrent or resistant infections require clinician-directed care. Prevention focuses on avoiding douching and scented products, choosing breathable clothing, and controlling blood sugar.

Vaginal yeast infection (vulvovaginal candidiasis, VVC) is a common condition caused most often by the fungus Candida albicans, and sometimes by other Candida species such as Candida glabrata. It causes local inflammation and discomfort rather than a systemic illness.

Who is at higher risk

Factors that increase risk include recent or prolonged antibiotic use, pregnancy, uncontrolled diabetes, and any condition that weakens the immune system (for example HIV). Hormonal changes, high estrogen exposure, and wearing tight or non-breathable synthetic underwear can also promote overgrowth.

Typical symptoms

The most common symptoms are intense vulvar itching and soreness. Women often report burning with urination, pain during sex (dyspareunia), and a thick, white, "cottage-cheese" vaginal discharge. Symptoms can range from mild to severe.

When to see a clinician

Seek medical evaluation for a first-time episode, severe symptoms, symptoms during pregnancy, recurrent infections (four or more in 12 months), or if you have diabetes or a weakened immune system. These situations may require testing and tailored treatment.

Diagnosis

Clinicians usually examine the vulva and vagina and may take a vaginal swab. Office tests include microscopy with saline and potassium hydroxide (KOH) to look for yeast forms, pH testing (vaginal pH in VVC is usually normal, typically ≤4.5), and laboratory culture or molecular tests when needed. Testing helps distinguish VVC from bacterial vaginosis or trichomoniasis, which require different treatments.

Treatment options

For uncomplicated VVC, topical azole antifungals (miconazole or clotrimazole) as creams or suppositories for 1-7 days are effective. A single oral dose of fluconazole (150 mg) is also commonly used for uncomplicated cases in nonpregnant patients. Oral azoles are avoided in pregnancy; topical azoles are preferred.

Recurrent or complicated cases may need longer courses, culture-directed therapy (especially for non-albicans species), or maintenance regimens (for example, weekly oral fluconazole for several months under clinician supervision). For azole-resistant infections, intravaginal boric acid capsules can be an option in nonpregnant adults but require medical guidance because boric acid is toxic if swallowed.

Male sexual partners generally do not need routine treatment unless they have symptoms (irritation or balanitis).

Prevention and self-care

Avoid douching and scented vaginal products. Choose breathable, loose-fitting clothing and cotton underwear. Replace sanitary products regularly during menses and maintain good glycemic control if diabetic. Probiotics and dietary changes have mixed evidence and should not replace medical treatment.

If symptoms persist after standard therapy or recur frequently, return to your clinician for re-evaluation and targeted testing.