Sexually transmitted infections (STIs) are often tricky to spot from symptoms alone. Most STIs go undetected – after all, most don’t produce any symptoms.
But when symptoms do appear, they can easily be confused for other conditions, some of which you might dismiss as unserious.
Thrush symptoms can often be mistaken for STI symptoms. It’s easy to understand why. Thrush and STIs can both affect the genitals can cause pain and irritation.
So, how do you tell?
Keep reading to find out.
If you think you may have an STI, you should get tested. Book an STI at a sexual health clinic near you today.
Thrush is a common yeast infection that affects both men and women. It’s caused by a fungus called candida, which is usually harmless.
A thrush infection can be triggered by factors that disrupt the natural balance of bacteria in your genitals, such as antibiotics, poorly controlled diabetes, a weakened immune system, pregnancy, or hormonal changes like menopause.
Wearing tight clothing, using perfumed hygiene products, or excessive washing can also contribute to its development.
A sexually transmitted infection is an infection that most people get through sex. They’re usually viruses, bacteria, or parasites that transfer from one person or the other during the sexual act.
The term “sexually transmitted infection” can be a bit misleading, though. While the vast majority of STIs transmit through sex, some STIs can be transmitted in other ways, like through kissing, foreplay, oral sex, sharing sex toys, and sharing needles.
Which is it: Thrush or STI?
It can sometimes be tricky to know from symptoms alone.
Even though Thrush is not recognised as an STI, symptoms can be similar to that of a sexually transmitted infection – making it difficult to know which one is causing your genital discomfort. Similarly, both Thrush and STIs may not present any symptoms even if you’re infected.
Thrush | Sexually Transmitted Infection |
Fungus | Bacteria, Virus or Protozoa |
A result of imbalanced bacterial populations, skin irritation or damage, antibiotics, poorly controlled diabetes, weakened immune system, pregnancy or if you have been through menopause. Sexual activity can sometimes trigger or pass on Thrush. | A result of unprotected sexual activity including oral, vaginal and anal intercourse. In some cases, direct skin-to-skin contact is enough to pass on an STI. |
Symptoms of Thrush can include: – White discharge from the vagina or penis (like cottage cheese) – Genital discomfort such as itching, redness – Pain or burning when urinating – An unpleasant odour – Soreness or stinging during sex Men might find it difficult to pull back foreskin | STI symptoms may consist of: – Unusual discharge from the vagina or penis – Cuts, blisters, ulcers or lesions – Genital or anal discomfort – Pain or burning when urinating – An unpleasant odour – Abnormal bleeding – Pelvic inflammatory disease – Increased need to urinate more often – Lower abdominal pain |
Treatment consists of antifungal medicine and creams that can help relieve irritation. | Depending on the STI you test positive for, antibiotics, antiviral or antiretroviral medication may be prescribed by a doctor. |
Thrush can clear up within a week with appropriate medication. In some cases, recurrent Thrush may require a longer course of treatment that can last up to six months. | Some sexually transmitted infections require long-term management. Symptoms of some STIs can be treated by surgical processes or over-the-counter creams. |
You can easily confuse Thrush for an STI because Thrush infections can often be triggered by sexual activity.
Sex can disrupt the natural balance of bacteria and yeast in the genital area. Friction during intercourse may cause micro-abrasions or irritation, making the skin more vulnerable to infection. Additionally, semen has a different pH than the vagina, and this shift in pH can create an environment where Candida albicans—the yeast responsible for Thrush—can thrive.
Telling the difference between a Thrush infection and an STI is difficult. Many of the symptoms are the same and with STIs there are frequently no symptoms at all. If you have had any kind of sexual encounter which you think might have put you at risk, then book an STI screen to make sure you don’t have an infection. If your test is negative you will feel happy and relieved, and if it’s positive, you can get treated and suffer no long-term ill effects.
Mike Asher, Co-Founder at Better2Know
Some STIs can produce similar symptoms that can be confused with the symptoms of Thrush.
Chlamydia can cause abnormal vaginal or penile discharge and pain during urination—symptoms that overlap with Thrush. Unlike Thrush, it may also lead to pelvic pain or bleeding between periods in women, and testicular discomfort in men.
Gonorrhoea often presents with a thick, yellow or green discharge and a burning sensation when urinating. These symptoms can resemble Thrush, especially when discharge and irritation are present.
Genital Herpes can cause itching, burning, and redness similar to Thrush. However, it’s usually accompanied by painful blisters or sores, which are not a feature of Thrush.
Trichomonas may cause a frothy, foul-smelling discharge, genital itching, and discomfort during sex—symptoms that can be mistaken for Thrush.
To prevent Thrush from reoccurring or to ease symptoms you can:
If you’re concerned about STIs, it might be best to avoid having sex. If you do engage in sexual activities, you should practice safe sex. You can do this through the consistent and correct use of barrier methods such as condoms and dental dams.
Sexual health clinics or private GUM clinics can provide treatment for thrush or sexually transmitted infections following a positive result. Your doctor or nurse may examine the vagina or penis and take a swab of discharge to test for infections. If you are concerned about any symptoms, or your sexual health more generally, you should get tested at your earliest convenience.
Don’t leave your sexual health to chance.
This article first appeared on 18/09/2020. Last updated 05/09/2025.