Vaginal itching, burning, and unusual discharge can come from at least three distinct conditions — yeast infection, bacterial vaginosis (BV), and trichomoniasis. The treatments are different, so getting the diagnosis right matters more than getting any prescription quickly. This guide walks through the symptom patterns and what treatment looks like for each. According to the CDC STI Treatment Guidelines, these three conditions account for the vast majority of acute vaginitis cases.

Yeast infection (vulvovaginal candidiasis)

Cause: overgrowth of Candida (usually albicans). Key symptoms: intense vulvar itching (hallmark), thick white cottage-cheese discharge, no strong odor, external dysuria, redness/swelling, dyspareunia. Treatment: single-dose oral fluconazole 150mg OR topical azole 1–7 days. Not sexually transmitted, partner treatment not needed. For symptom details, see yeast infection symptoms.

Bacterial vaginosis (BV)

Cause: shift in vaginal flora (decreased Lactobacillus, increased Gardnerella and other anaerobes). Key symptoms: thin gray-white discharge, fishy odor (often worse after sex), mild itching or none, often no inflammation. Treatment: oral metronidazole 500mg twice daily for 7 days OR vaginal clindamycin cream. BV is the most common cause of abnormal vaginal discharge in reproductive-age women per the CDC — not sexually transmitted but associated with sexual activity.

Important: antifungals don't treat BV. If you have BV symptoms (especially the fishy odor) and use Monistat, you'll get no benefit and waste $20.

Trichomoniasis

Cause: Trichomonas vaginalis, a protozoan parasite — sexually transmitted. Key symptoms: frothy yellow-green discharge with strong odor, intense itching and irritation, dysuria, sometimes "strawberry cervix" on exam. Up to 50% of women with trich are asymptomatic. Treatment: single-dose oral metronidazole 2g OR tinidazole. Sexual partners must be treated to prevent reinfection. The CDC recommends testing for other STIs (HIV, gonorrhea, chlamydia) when trich is diagnosed.

The decision matrix

Itching dominant + thick white discharge + no odor: likely yeast.

Fishy odor + thin gray discharge + mild itching: likely BV.

Yellow-green frothy discharge + intense itching: trich — needs STI workup.

When the picture is mixed or unclear: in-person evaluation is the safer path. Lab testing (wet mount, vaginal pH, KOH prep, or NAAT) gives a definitive answer.

What CodyMD treats vs what needs in-person care

CodyMD's licensed physicians can prescribe single-dose fluconazole for uncomplicated yeast when symptoms match the classic picture. For BV in patients with a clear history of recurrence and prior diagnosis, oral or topical treatment may be appropriate. For trich or any STI concern, the doctor will recommend in-person evaluation — STI testing and partner notification can't be done by text. For the full visit walkthrough, see online yeast infection treatment.

Bottom line

Three conditions, three treatments. The symptom pattern usually points the way, but unclear cases benefit from in-person testing. A licensed CodyMD doctor will tell you what fits and what doesn't — if it's classic yeast, the prescription is at your pharmacy in 1 hour.