It can be difficult to distinguish between common vaginal infections. Christine Clarke explains how they are different and what treatments they require
Key learning points
• Acute vaginal thrush causes extreme discomfort and requires prompt, effective treatment
• Bacterial vaginosis is usually associated with a vaginal discharge but not the fierce itching of thrush, and can be treated with an OTC product
• The OTC azole treatments can provide an 80-95% clinical and mycological cure rate in acute thrush
Vaginal or vulval discomfort can be very distressing and embarrassing. Vaginal thrush and bacterial vaginosis can be treated with over-the-counter (OTC) products, but other conditions call for medical attention. Giving patients clear information in a sensitive and supportive way can help them deal with these conditions promptly and effectively.
Vaginal thrush (vaginal candidiasis or moniliasis) is estimated to affect three-quarters of all women at least once in their lives, and many experience more than one episode. It is caused by overgrowth of a yeast (single-celled fungus) Candida albicans,
a usually harmless commensa. It does not normally grow in the vagina because the flora – lactobacilli – maintain an acidic environment that is unfavourable for fungal growth.
Warm, moist conditions favour fungal growth. Predisposing factors for thrush include diabetes, immunosuppression, broad-spectrum antibiotic treatment, use of douches and vaginal deodorants, pregnancy and wearing occlusive underwear. Thrush is most common during the reproductive years.
The most obvious symptom is intense itching in the vulvovaginal area. This is often accompanied by a discharge that can be creamy coloured and thick or curdy or thin and watery. The vulva can be sore and inflamed from repeated scratching and there can be stinging on passing urine. Vaginal thrush is not considered to be a sexually transmitted disease but it can be passed to the male sexual partner and cause inflammation of the penis head (balanitis).
Typically a patient might say: ‘I’ve been suffering with thrush for three days now. The itching has been horrendous.’
Many women recognise the symptoms and seek treatment but thrush can be confused with other conditions including:
• Bacterial vaginosis (BV), which is caused by overgrowth of mixed bacterial organisms, mainly anaerobes. BV causes a discharge and the vagina pH rises above 4.5.
• Trichomoniasis, caused by infestation with the parasite Trichomonas vaginalis, which is sexually transmitted.
• Cystitis, caused by bladder infection, can cause discomfort on passing urine but is usually accompanied by other symptoms including frequent urination and lower abdominal pain.
• Cervical erosions, which can be associated with pain on urination, bleeding after sex and a vaginal discharge that may be bloodstained.
• Atrophic vaginitis, which in post-menopausal women can also cause discomfort including a burning sensation, with or without a vaginal discharge, and frequent urination.
Recurrent thrush (more than two episodes in six months) is a problem for some women and can be caused by, for example, reinfection from a reservoir in the bowel or from the sexual partner. It may indicate an underlying factor such as diabetes.
It is not a contra-indication to OTC treatment but patients should be advised to seek medical attention to investigate the cause. Recurrent thrush can be treated with oral fluconazole. However, this is outside the marketing authorisation for OTC fluconazole.
Treatment of vaginal thrush
The goals of treatment are to eliminate the infection, treat the itching and minimise the risks of recurrence.
All intravaginal and oral azole treatments can provide an 80-95% clinical and mycological cure rate in acute thrush in non-pregnant women. Two such agents are available as OTC products.1 Pessaries should be inserted high up in the vagina using either the applicator or a finger. Cream should be offered for the external itching.
Available as a 500mg pessary, a 5g prefilled, single application of 10% cream for intravaginal use and 2% cream for external use. Combination packs are also available.
Available as a single-dose 150mg oral capsule. Fluconazole is well absorbed and symptoms usually improve after 12 to 24 hours. Adverse effects are mild and mainly gastrointestinal, including abdominal pain, diarrhoea, nausea and vomiting and flatulence.
Fluconazole interacts with a number of drugs, including those metabolised by cytochrome P450 enzymes, but interactions are unlikely to be significant with a single dose of fluconazole. Oral fluconazole is contra-indicated if pregnant or breastfeeding.
Briefs made of pure fibroin impregnated with a permanent antimicrobial protection agent (Dermasilk Intimo) can be helpful to women with recurrent thrush. One randomised controlled trial compared the effect of wearing Dermasilk briefs with plain cotton briefs in women with recurrent vulvovaginal candidiasis. They all received weekly fluconazole 150mg for six months. The Dermasilk group experienced significantly less itching, burning and erythema and fewer recurrences.
The effects are related to contact between skin and fabric so the briefs have to be worn for as much of the time as possible. Conventional silk fabric does not have this therapeutic effect.
Natural yoghurt, probiotics and prebiotics
The role of natural yoghurt and, in particular, probiotic yoghurt, is often discussed for this condition. There is some evidence for the effectiveness of intravaginal yoghurt, alone or mixed with honey. One small trial showed that eating probiotic yoghurt also reduced candida colonisation of oral and vaginal mucosa. Canesflor delivers lactobacilli to the vagina in pessaries.
An alternative approach is prebiotics – agents that create a favourable environment for lactobacilli such as Multi Gyn Floraplus. These are presented in single-use tubes for vaginal administration.
There is no firm evidence that either probiotics or prebiotics can cure vaginal candidiasis but they may prevent recurrence.
Bacterial vaginosis (BV)
BV is caused by growth of a mixed population of bacteria in the vagina. It is usually associated with a watery or greyish-white discharge with a fishy or unpleasant odour. Lactobacilli are lost from the vaginal flora and the pH rises above 4.5. Recurrent disease is not uncommon and it can be associated with pelvic inflammatory disease, preterm labour and susceptibility to sexually transmitted diseases.
The goals of treatment are to eliminate the infection, manage the symptoms and minimise the risks of recurrence.
The standard treatment is oral metronidazole, 400mg twice daily for five to seven days. Alternatives are intravaginal metronidazole gel 0.75% or intravaginal clindamycin cream 2% if the patient
cannot tolerate oral metronidazole.
Multi Gyn ActiGel is an OTC treatment for BV. This is an intravaginal, acidic gel containing a polysaccharide (2QR-complex). This interferes with bacterial adhesion. 
The patient should be referred if:
• There is uncertainty about the diagnosis.
• OTC treatment is not suitable.
• Has symptoms of vaginal infection for the first time.
• Is under 16 or over 60 years.
• Has recurrent disease (eg thrush more than twice in six months).
• Has not responded to treatment.
• Is pregnant or breastfeeding.
• Is immunosuppressed.
• Has abnormal or irregular vaginal bleeding or blood-stained discharge; vulval or vaginal sores, ulcers or blisters; lower abdominal pain or dysuria or a history of sexually transmitted disease.
Other measures and general advice
Women with vaginal infections are most worried about feeling clean and comfortable and not smelling. The following measures can help:
• Wearing cotton or Dermasilk briefs and avoiding tight trousers.
• Using products formulated to cleanse and protect the area such as Multi Gyn IntiSkin and IntiFresh.
•Sexual intercourse should be avoided until cure is complete, to avoid transfer of infection and/or reinfection.
•After bowel movements, the anus should be wiped from front to back to avoid transfer of organisms from the bowel to the vagina.
Dr Christine Clark is an independent dermatology pharmacy consultant and freelance medical writer
1 National Guideline on the Management of Vulvovaginal Candidiasis. British Association for Sexual Health and HIV bashh.org/
2 D’Antuono A, Baldi E, Bellavista S et al. Use of Dermasilk briefs in recurrent vulvovaginal candidosis: safety and effectiveness. Mycoses 2012;55:e85-89
3 Bojovic T, Bojovic D, de la Tour F-X B et al. first line treatment and relief of bacterial vaginosis-related vaginal complaints with metronidazole and Multi-Gyn®