What causes a very itchy vagina inside and out and how is it treated?

Vaginal Itching: Causes and Treatment

Most Likely Diagnosis

The most common cause of severe vaginal itching both inside and outside the vagina is vulvovaginal candidiasis (yeast infection), which should be confirmed with vaginal pH testing and microscopy before treatment. 1

Diagnostic Approach

Key Clinical Features to Assess

• Pruritus is the hallmark symptom of vulvovaginal candidiasis, with erythema in the vulvovaginal area; white discharge may or may not be present 1
• None of the symptoms are specific for any single condition, making objective testing essential 2, 1
• The absence of itching should prompt consideration of alternative diagnoses rather than yeast infection 1

Essential Diagnostic Tests

• Vaginal pH testing is the critical first step:

  • pH <4.5 suggests vulvovaginal candidiasis 2, 1
  • pH >4.5 suggests bacterial vaginosis or trichomoniasis 2, 1

• Wet mount microscopy with 10% KOH preparation:

  • Detects yeasts or pseudohyphae in 50-70% of candidiasis cases 1
  • Identifies clue cells for bacterial vaginosis 2
  • May reveal motile trichomonads 2

• Culture should be obtained if microscopy is negative but clinical suspicion remains high, as culture is more sensitive than microscopy 1

Treatment for Vulvovaginal Candidiasis

First-Line Options

For uncomplicated cases, choose either oral fluconazole 150 mg as a single dose OR short-course topical azole therapy. 2, 1

Specific Regimens (80-90% effective)

Oral therapy:

• Fluconazole 150 mg tablet, single dose 2, 3

Topical therapy (equally effective):

• Clotrimazole 500 mg vaginal tablet, single application 2
• Miconazole 200 mg vaginal suppository, one daily for 3 days 2
• Terconazole 0.8% cream 5g intravaginally for 3 days 2

Important Treatment Considerations

• Short-course regimens (1-3 days) are as effective as longer courses for uncomplicated cases 1
• Oil-based creams and suppositories weaken latex condoms and diaphragms 2
• Over-the-counter preparations should only be used by women previously diagnosed with vulvovaginal candidiasis who recognize recurrent symptoms 2

Alternative Diagnoses to Consider

Bacterial Vaginosis

• Presents with homogeneous white discharge, pH >4.5, positive whiff test (fishy odor with KOH), and clue cells on microscopy 2, 1
• Requires 3 of 4 Amsel criteria for diagnosis 2
• Treated with metronidazole or clindamycin, NOT antifungals 4

Trichomoniasis

• Associated with pH >4.5 and motile trichomonads on wet mount 2
• Requires treatment with metronidazole or tinidazole 4

Non-Infectious Causes

• Chemical or mechanical irritation can cause itching without infection 1
• Atrophic vaginitis in postmenopausal women requires hormonal therapy 5
• Inflammatory dermatologic conditions may require steroid application 4

Critical Pitfalls to Avoid

• Do not treat based on symptoms alone without confirming diagnosis, as inappropriate treatment delays correct diagnosis and can worsen outcomes 2
• Seek medical evaluation if symptoms persist after OTC treatment or recur within 2 months 2
• Do not assume all vaginal itching is yeast - bacterial vaginosis accounts for 40-50% of vaginitis cases when a cause is identified, compared to only 20-25% for candidiasis 4
• Partner treatment is NOT recommended for vulvovaginal candidiasis, as it is not sexually transmitted 2

When to Seek Immediate Medical Care

• Symptoms persist after completing treatment 2
• Recurrence within 2 months of initial symptoms 2
• Four or more episodes per year (recurrent vulvovaginal candidiasis requiring different management) 2
• Pregnancy, diabetes, or immunocompromised state 3