Thrush or STI: how to know the difference

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 are sometimes 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.

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What is Thrush?

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.

What is an STI?

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.

Is Thrush an STI?

Although Thrush can often occur after sex, it is not sexually transmitted. There is an exchange of bacterial flora between people in sex, which may break down the natural protection your flora provides, and so unleashing an outbreak of thrush.

So, 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.

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 for some people. Some of the symptoms are the same and with STIs there are frequently no symptoms at all. But in women, the symptoms will usually be due to irritation in the vagina or vulva, whereas many STIs like Chlamydia will produce symptoms “further inside”, with symptoms being deeper as it is the cervix that gets infected. 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. However, if you have symptoms and your tests are negative, please make sure you speak to your doctor to find out alternative causes.
Mike Asher, Co-Founder at Better2Know

What STIs can be mistaken for Thrush?

Some STIs can produce similar symptoms that can be confused with the symptoms of Thrush.

Chlamydia

Chlamydia can cause abnormal vaginal discharge pain during urination—symptoms that could overlap with Thrush – there may also occasionally be vaginal redness that confuses us. Unlike Thrush, it may also lead to pelvic pain or bleeding between periods in women, and testicular discomfort in men.

Gonorrhoea

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

Genital Herpes can cause some 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

Trichomonas may cause a frothy, foul-smelling discharge, genital itching and redness, as well as discomfort during sex—symptoms that can be easily mistaken for Thrush.

Gardnerella

Gardnerella can be very difficult to distinguish from thrush as it also produces, genital itching and redness, but usually there is also a change in smell.

Preventing Thrush symptoms

To prevent Thrush from reoccurring or to ease symptoms you can:

Wear cotton underwear
Avoid sex until Thrush has cleared
Use a condom to prevent transmission to your partner
Taking showers instead of baths, but avoid excessive hygiene
Use water or emollient body washes to clean the vagina or penis
Dry the area properly after washing

Preventing sexually transmitted infections

If you’re concerned about STIs and you’re sexually actives, you should practice safe sex. You can do this through the consistent and correct use of barrier methods such as condoms and dental dams.

Get tested at a sexual health clinic near you

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.