Reasoning GP · Algorithm · 1-page summary
Vaginal discharge in adults
For: adults aged ≥16 with vaginal discharge. Not for: children and young people — local paediatric and safeguarding pathways; no internal examination in primary care. Local sexual-health guidance takes precedence.
Core rule: discharge features are suggestive, not diagnostic. Treat PID early and empirically — delay risks tubal infertility and ectopic pregnancy — and examine the cervix in any blood-stained or persistent discharge.
0Stop — call 999 now — before routine management
- Suspected sepsis (NEWS2) with instability, confusion or poor perfusion; peritonism; suspected ruptured tubo-ovarian abscess → 999 / sepsis pathway (NG253).
- Toxic shock: fever, rash, vomiting or diarrhoea, hypotension or confusion with a tampon, cup or foreign body in place → remove it if easily accessible → 999
- Anaphylaxis, angioedema or severe rash after treatment → 999; document and avoid the drug.
- Pregnant and unstable → 999. Suspected intra-amniotic infection, PPROM, significant bleeding or maternal or fetal compromise → Same-day maternity, discussed promptly.
1Triage — who needs more than a swab
| Feature | Action |
|---|---|
| Pelvic pain | + cervical motion, uterine or adnexal tenderness → PID; exclude ectopic and surgical causes |
| Could be pregnant | Pregnancy test if uncertain and treatment would change |
| Recent procedure | Hysteroscopy, IUD insertion, caesarean, termination → Same-day gynae |
| STI risk | New partner in 3 months, under 25, several partners → NAAT |
2Screen — one row is enough
- PID with systemic illness, severe pain, suspected abscess, pregnancy, diagnostic doubt, can't take oral treatment or no better at 72 h → Same-day gynae / admit
- Suspicious cervical lesion → Urgent suspected cancer. Unexplained postmenopausal bleeding → Suspected cancer pathway
- Age 55+, unexplained discharge: first presentation, or with thrombocytosis or haematuria → consider urgent direct-access USS (NG12)
- Gonorrhoea confirmed or strongly suspected → Urgent sexual health
- Immunocompromised, severe or atypical → low threshold for admission. Assault or coercion → local safeguarding pathway.
3Assess — chaperone offered and documented
☐ Obs; NEWS2 if unwell ☐ Vulva: ulcers, lichen sclerosus ☐ Speculum if acceptable: friable cervix, contact bleeding, foreign body ☐ Vaginal pH: >4.5 BV or TV; ≤4.5 candida or physiological ☐ Bimanual if PID is possible ☐ Self-taken vulvovaginal NAAT; gonorrhoea culture before treatment if feasible, never delaying it ☐ HIV and syphilis tests by risk
Don't order: CA-125, routine urine culture, HVS if asymptomatic, Gardnerella or Ureaplasma tests.
4Classify — only if the screen is negative
- BV — thin grey/white, fishy odour, pH >4.5, clue cells → treat.
- Candida — itch, thick white curdy, pH ≤4.5 → antifungal.
- Trichomonas — frothy yellow-green, pH >4.5 → NAAT; treat with partners.
- Chlamydia, gonorrhoea, cervicitis — mucopurulent, friable cervix; often silent → NAAT.
- Atrophic — postmenopausal, dry → topical oestrogen. Physiological — cyclical, no odour or itch → reassure once pathology excluded.
- Uncertain or persistent → review and escalate; don't repeat empirical treatment.
5Treat today — doses: NICE, SPC and local formulary
- PID, today, not waiting for swabs: ceftriaxone 1 g IM + doxycycline 100 mg BD + metronidazole 400 mg BD 14 days; review at 72 h. No routine fluoroquinolone.
- BV: metronidazole 400 mg BD 5–7 days, 0.75% gel or clindamycin cream (weakens latex); no 2 g stat in pregnancy. Candida: clotrimazole 500 mg pessary or fluconazole 150 mg; pregnant: topical imidazole 7 days, no fluconazole.
- TV: metronidazole 400–500 mg BD 7 days. Chlamydia: doxycycline 100 mg BD 7 days; pregnant: azithromycin 1 g then 500 mg daily 2 days, test of cure ≥3 weeks. Gonorrhoea: ceftriaxone 1 g IM, specialist-led.
- STI: partner notification; no sex until both treated.
6Refer routinely
- Sexual health: STI screen and contact tracing; possible LGV, syphilis, M. genitalium; BV or candida not responding.
- Recurrent candida (≥4 a year): culture, HbA1c, fluconazole induction then weekly for 6 months. Gynaecology: candida not responding, vulval biopsy, suspected fistula.
7Never reassure by
- Colour or odour alone — it doesn't separate BV, trichomonas, gonorrhoea and cervicitis.
- A negative trichomonas wet mount.
- Waiting for swab results before treating suspected PID.
- A normal cervical screening result when discharge is blood-stained or persistent.
- Skipping vulval inspection (lichen sclerosus, herpes, syphilis).
- Repeated empirical courses for persistent unexplained discharge.
8Safety-net — say it, then document it
999 “Call 999 for worsening fever and pelvic pain on antibiotics, severe tummy pain or fainting; face, lip or tongue swelling or difficulty breathing after treatment; or fever, rash, vomiting or feeling faint with a tampon or other item inside.” Same day “Contact us today for pelvic pain with fever, feeling unwell, no better after 72 hours of PID treatment, new fever, blood-stained discharge or new bleeding, any pregnancy worry, or can't keep tablets down.”
Return if discharge persists or recurs → reassess, examine the cervix. Chase swabs; confirm partner notification. Remote: PID possible → examine face to face the same day.
✓Safe to leave primary care only if — all five, documented
No block 0–2 row applies
Pregnancy status known where it changes treatment
Vulva and pH checked; bimanual if pain; NAAT by risk
Cause named, or uncertainty stated with a review date
Partner notification and safety-net given; results chased
Summary of the full Reasoning GP vaginal discharge algorithm, which holds the detail and evidence. Sources: IUSTI/BASHH vaginal discharge 2023; BASHH BV 2012, candidiasis 2019, Trichomonas 2021, PID 2019, chlamydia 2026, gonorrhoea 2025; local antimicrobial guidelines; NICE NG12 (updated April 2026), NG253, NG201, NG23; MHRA fluoroquinolones 2024. Reference only — follow local pathways; check doses in the SPC and your local formulary.