Is It Vaginal Thrush (Candidiasis)? Symptoms, Causes, Treatment & When to See a Specialist

Vaginal health is a vital component of overall wellbeing, yet many people find it difficult or embarrassing to discuss the discomfort that can arise “down there”. Vaginal thrush is a very common condition that affects most women at some point in their lives. While it is usually harmless, the itching and soreness it causes can be distressing and disruptive.

Understanding what causes these symptoms and how to manage them is the first step toward reclaiming your comfort and confidence.

What Is Vaginal Thrush (Candidiasis)?

Vaginal thrush is a common yeast infection caused by an overgrowth of a fungus called Candida, most often Candida albicans. It is medically known as candidiasis.

It is important to understand that Candida is not an “invader”. In fact, it can live naturally and harmlessly in the mouth, digestive tract, and vagina of healthy people. In a balanced environment, “friendly” bacteria (specifically Lactobacillus) keep the yeast levels in check. However, if the delicate balance of the vaginal flora is disrupted, the yeast can multiply rapidly, leading to the inflammation and discharge we recognise as an infection.

In many parts of the world, this is simply referred to as a “yeast infection”. While it is not a sexually transmitted infection (STI), it can sometimes be triggered by sexual activity or passed between partners.

What Are the Symptoms of Vaginal Thrush?

Symptoms can range from mild irritation to significant discomfort. These symptoms occur because yeast overgrowth causes inflammation of the vaginal lining and vulval skin. This inflammation irritates nerve endings and disrupts the protective mucosal barrier, which explains why even mild infections can feel intensely uncomfortable.

The most common signs of vaginal thrush include:

• Vaginal itching, often most noticeable around the entrance of the vagina (the vulva)
• A burning or stinging sensation, particularly when urine passes over inflamed skin or during sexual intercourse
• White, thick, odourless discharge, often described as looking like “cottage cheese”
• Redness and swelling of the vulval skin
• Pain during sex due to inflammation

Some people experience thrush without significant discharge. In these cases, itching and soreness may be the main symptoms. If you notice a strong or “fishy” odour, it is less likely to be thrush and may indicate a different condition, such as bacterial vaginosis (BV).

What Causes Vaginal Thrush?

Because Candida is already present in the body, an episode of thrush is usually triggered by a change in your internal environment rather than “catching” it from someone else.

Antibiotics are one of the most common triggers. While they are effective at treating harmful bacteria, they can also wipe out the protective bacteria that normally keep yeast levels under control.

Hormonal changes can also contribute. Higher oestrogen levels during pregnancy or at certain points in the menstrual cycle can alter the sugar content of the vaginal lining, encouraging yeast growth. 

Similarly, if blood sugar levels are poorly controlled in diabetes, the increased glucose in vaginal secretions provides a food source for the fungus.

A weakened immune system — whether due to illness, chemotherapy, or long-term steroid use — can make it harder for the body to regulate yeast levels. 

Lifestyle factors such as tight-fitting synthetic clothing, scented soaps, or sitting in wet swimwear for long periods may also create the warm, moist environment where yeast thrives.

Is Vaginal Thrush an STI?

It is a common misconception that vaginal thrush is a sexually transmitted infection. It is not.

Thrush is caused by an overgrowth of fungus that is already part of your natural microbiome. However, sexual activity can sometimes alter the vaginal pH or cause minor friction, which may trigger symptoms in some individuals. Although it is not classified as a sexually transmitted infection, sexual activity can sometimes trigger symptoms, yeast may occasionally be shared between partners, and sex during an active infection may feel uncomfortable due to existing inflammation.

If symptoms appear after a new sexual partner, it may still be sensible to consider STI testing to rule out other causes of irritation.

Why Does Thrush Keep Coming Back? (Recurrent Thrush)

For some, vaginal thrush becomes a recurring issue, defined as having four or more episodes within a single year. This can be incredibly frustrating.

When infections keep returning, it often suggests that something is preventing the vaginal microbiome from fully stabilising. Common contributing factors include:

• Resistant or non-albicans Candida strains, which may not respond well to standard over-the-counter treatments
• Underlying health issues, such as undiagnosed diabetes or immune fluctuations
• Persistent microbiome imbalance, where protective bacteria struggle to re-establish themselves after treatment

Some resistant strains form protective biofilms — structured communities of yeast cells that make them harder to eradicate with short-course antifungals. In these cases, longer suppressive therapy may be required.

If you are experiencing frequent flare-ups, specialist assessment allows for strain identification and tailored management.

Vaginal Thrush vs Other Conditions

Because many genital conditions cause itching or redness, it is easy to misdiagnose yourself. However, not all irritation is caused by yeast. It is important to distinguish thrush from:

• Bacterial Vaginosis (BV): BV usually causes a thin, greyish discharge with a strong fishy smell but rarely causes significant itching.
• Vaginitis/Vulvar Dermatitis: Irritation caused by reactions to detergents, soaps, or condoms can look like thrush but requires different management.
• Genital Psoriasis or Lichen Sclerosus: These are dermatological skin conditions that cause intense itching and skin changes but are not fungal infections.

If symptoms do not follow the classic thrush pattern, laboratory confirmation can prevent unnecessary repeated antifungal use.

How Is Vaginal Thrush Diagnosed?

Diagnosis begins with a discussion of symptoms and, if appropriate, a physical examination.

If the symptoms are persistent or unusual, our Specialists may perform a vaginal swab. This involves a gentle wipe of the vaginal wall with a small cotton bud. The sample is then tested to confirm the presence of Candida and to ensure there isn’t a co-existing infection or a more resistant strain of yeast that requires specific medication.

Treatment for Vaginal Thrush

The goal of treatment is to reduce the amount of yeast to a normal, manageable level. Options include:

• Antifungal Creams and Pessaries: These are applied directly to the vulva or inserted into the vagina (using an applicator) to treat the infection at the source. Clotrimazole is a common active ingredient.
• Oral Antifungals: A single tablet (Fluconazole) is often highly effective for uncomplicated thrush.
• Prescription-strength or extended treatment courses: If over-the-counter options haven’t worked, our Specialists can prescribe higher-strength or longer courses of treatment, particularly for recurrent cases.

Most infections clear up within three to seven days of starting treatment.

Can You Treat Thrush at Home?

Many people find relief using over-the-counter treatments available at a local chemist. This is often appropriate if you have had thrush before and clearly recognise the symptoms.

However, home treatment may not be enough if symptoms do not improve after a few days, if you are pregnant, or if you have had more than two infections within six months. In these situations, medical advice is recommended.

We generally advise against “home remedies” such as tea tree oil or yoghurt, as these can irritate delicate vaginal tissue and disrupt the natural pH balance.

Can Men Get Thrush?

Yes, men and people with a penis can develop thrush, often referred to as candidal balanitis. Symptoms usually include redness, itching, or a small rash on the head of the penis (the glans), particularly in people who are uncircumcised.

While it isn’t always necessary to treat a partner who has no symptoms, if both partners are experiencing irritation, treating both simultaneously can help prevent the infection from being passed back and forth.

When Should You See a Specialist?

Whilst vaginal thrush is usually a minor health concern, there are times when professional guidance is essential. You should book a consultation with our Specialists if:

• It is your first episode
• You are pregnant
• The symptoms are severe, with sores or significant swelling
• Over-the-counter treatment has not worked
• The infection keeps coming back

At our clinic, we provide a supportive and confidential environment to discuss your genital health. Whether you need a simple test for peace of mind or a comprehensive plan for recurring symptoms, our Specialists are here to help you feel like yourself again.