Thrush, also known as candidiasis, is a yeast infection caused by overgrowth of Candida — a fungus that naturally lives in the body. It is not a sexually transmitted infection, but its symptoms can closely mimic those of several STIs including BV, trichomoniasis, and chlamydia. This is why testing is important rather than self-diagnosing or purchasing over-the-counter treatments without confirming the cause. According to the Australian STI Management Guidelines, vaginal discharge should be investigated to rule out STIs before assuming the cause is thrush.
Thrush typically causes a thick, white, cottage-cheese-like vaginal discharge accompanied by itching, redness, and irritation of the vulva and vagina. In men, thrush can cause redness, itching, and irritation of the head of the penis, particularly in uncircumcised men. Thrush is more common during pregnancy, after antibiotic use, in people with diabetes, and in those with weakened immune systems. Approximately 75 per cent of women will experience at least one episode of thrush in their lifetime.
Testing for thrush involves a vaginal swab that can be self-collected at a pathology clinic. The swab is cultured to identify whether Candida is present and which species is involved — this matters because some species respond differently to antifungal medications. At Clinic365, the $39 online test includes a self-collect vaginal swab alongside the standard five-infection STI screen, so thrush and the most common STIs are all tested in a single visit.
There is no specific window period for thrush — it can occur at any time due to changes in the vaginal environment. Common triggers include antibiotics, hormonal contraception, pregnancy, diabetes, stress, and wearing tight or synthetic underwear. If you experience thrush four or more times per year, this is classified as recurrent vulvovaginal candidiasis and may require a longer or different treatment approach under the guidance of a specialist.
Treatment for uncomplicated thrush is typically a single dose of oral antifungal medication or a short course of topical antifungal cream or pessaries. Over-the-counter treatments are available at pharmacies, but a confirmed diagnosis through testing is recommended — particularly for a first episode, recurrent episodes, or if symptoms persist after treatment. Your Specialist GP can prescribe appropriate treatment and develop a prevention plan if thrush is recurrent. Sexual partners generally do not require treatment unless they have symptoms.
Regular sexual health screening is recommended for anyone who is sexually active, even when no symptoms are present. Most sexually transmitted infections produce no noticeable symptoms in the early stages, which means they can be unknowingly passed to sexual partners. Australian guidelines recommend at least annual screening for sexually active adults, and more frequent testing for those with new or multiple partners. If you have had unprotected sex with a new partner, testing is recommended even if you feel well.
If your test results are positive, your Specialist GP will contact you directly to discuss treatment options and arrange treatment. Most bacterial STIs respond well to a short course of antibiotics and are straightforward to manage when detected early. Partner notification is an important part of treatment — all recent sexual partners should be informed and tested, even if they have no symptoms. Your GP can advise on how to approach this conversation, including anonymous notification options if preferred.