Hormone replacement, Women's Health | October 13, 2015 | Author: The Super Pharmacist
Vulvovaginal candidiasis, also known as thrush, is a yeast infection of the lower female reproductive tract. The infective organism is a fungus, with an estimated 90% of cases caused due to Candida albicans. Other organisms that cause vulvovaginal candidiasis include Candida glabrata, Candida krusei, and Candida parapsilosis.
Anti-thrush medication is available in a number of formats. These include pessaries (inserted into the vagina with an applicator), topical creams to deal with Candida on the skin around the entrance to the vagina, and tablets that are administered orally. The literature suggests that there is very little difference in both the efficacy and safety of topical and oral azole therapies. They are all considered to have a cure rate in excess of 80% when used to treat acute vaginal and vulval candidiasis (1), with the particular drug choice for a patient usually being based on personal or professional preference (and, in countries where patients are required to pay for their medication, affordability). Some drugs offer a slightly higher cure rate, with both Nystatin vaginal cream (at 4g over 14 days) and Nystatin pessaries (taken 1-2 times over 14 days) evidencing a cure rate in excess of 90% (2). For single episodes of candidiasis, an intravaginal antifungal (such as clotrimazole or miconazole pessaries) or an oral antifungal (such as fluconazole or itracanazole) are predominantly used. Where vulval symptoms are present, a topical application is also often considered as a combination treatment option (combination packs of pessary/vaginal creams and topical creams tend to be readily available over the counter and are safe to administer together). A systematic review of topical versus intravaginal creams, undertaken by The Cochrane Collaboration, found that topical creams can cause some additional itching and burning symptoms in the first 48 hours of use (3) – although there is no safety risk in using topical treatments, some patients may opt for an oral treatment to prevent any existing symptoms from being exacerbated. A number of studies have highlighted that a number of vaginal/vulval antifungal treatments such as clotrimazole, fenticonazole, econazole and miconazole may potentially damage latex condoms (4). As such, treatment options from within this group are often prescribed along with advice to abstain from sexual intercourse or use non-latex barrier methods both during and shortly after treatment. Treatment for pregnant women generally recommends intravaginal clotrimazole or micronazole, with both evidenced to be equally effective as the other over a treatment period of six to seven days (5). Although no more clinically effective than topical applications, some women may prefer to administer pessaries to avoid any potential damage to the cervix. Oral fluconazole and itraconazole are contraindicated in pregnancy and should never be prescribed to, or used by, pregnant women (6). Patients who are immunocompromised (particularly those with HIV or diabetes) are advised to take medication for 14 days as opposed to a standard 6-7 day course (7).
There is some evidence to suggest that three 150mg doses of fluconazole taken 72hrs apart from each other, or a topical imidazole treatment taken over a course of 10-14 days, is the optimum induction treatment for women who have persistent or recurrent candidiasis (8). Historically, the at risk period for developing recurrent vulvovaginal candidiasis (RVVC) would have been much shorter than it is at present – the period of time in which many women are left susceptible to RVVC has been significantly extended in line with the widely increased use of hormone replacement therapy to prolong menopause. The use of fluconazole maintenance suppressive therapy remains the recommended first line treatment option for RVVC, yet increasing levels of fluconazole drug resistance do pose a potential threat to its efficacy as a treatment option for many women (9). There is a relatively limited evidence base in regards to longer term treatment for RVVC, but there is some evidence to suggest that 500mg of intravaginal clotrimazole once weekly is effective as a maintenance option (10). There is also some limited evidence that switching to a progestogen only injectable contraceptive can help relieve symptoms in women who experience RVVC, but the number of studies focused on this area is small and there are a wide range of confounding factors that make it difficult to attribute any improvements or alleviation of symptoms solely to a change in contraceptive (11). Patients who take orally administered fluconazole and are responsive to it have been evidenced to have a greater chance of remaining disease free during the follow up period than those treated with other antifungal agents (12). The management of recurrent infections also requires attention to a range of non-pharmaceutical treatments such as using a soap substitute to clean the vulval area, avoiding topical irritants, maintaining general good hygiene, using an emollient to moisturise the vulval skin, and wearing loose fitting underwear.