The V Book - Chapter 10: Yeast Infections

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CHAPTER 10: Yeast Infections
Separating the Truths from the Popular Beliefs
Yeast. It's the first thing most women think of when they experience V symptoms. Got an itch? Buy a tube of cream. If only it were that simple every time.
Yeast infections are harder to diagnose and self-treat than women have been led to believe. Though yeast infections are the most familiar V condition, they're not the commonest. (That distinction goes to bacterial vaginosis.) The hallmark irritation and discharge that lead many women to think "yeast infection" unfortunately characterize many other conditions as well. Grabbing a tube of OTC antifungal cream at your local drugstore won't do you any good—or could even make things worse—if yeast isn't the problem. Consider these examples:
Anne experiences vulvovaginal irritation, checks herself, and finds thick white vaginal discharge, so she concludes that she has a yeast infection. She goes to the drugstore and purchases an OTC yeast cream. It doesn't work. Why? She doesn't realize it, but the irritation is from exercising in thong underwear, and the suspicious discharge is actually normal.
Sonya decides her inflammation and discharge stem from a yeast infection. When OTC cream does not help her, she sees me, and I diagnose the sexually transmitted disease chlamydia.
Beth, who's pregnant, thinks she has yeast. Sure enough, I find that her discharge sticks to the side walls of the vagina and covers the cervix, suggesting yeast. But when I examine some secretions under the microscope, I discover she has bacterial vaginosis.
Marina complains of having yeast symptoms all the time. In addition to a constantly itchy sensation, sex hurts. Though she's tried many yeast creams, they never clear up the symptoms. Turns out she doesn't have yeast; it's vulvodynia.

I don't mean to suggest that every time you think you have a yeast infection, it's probably something else. Yeast infections do happen, and often. But folklore about yeast has outpaced hard medical facts, leading to way too much assumed knowledge (which is often, as you'll see, incorrect or inconclusive). Take the following folk wisdoms, for example: Yeast causes a cottage-cheese-like discharge with intense itching. Too many sweets cause yeast. To prevent yeast you should eat yogurt and wear white cotton underwear. All these statements have come to be accepted as fact. However, some are only partially true; others have little or no scientific research to support them.
Misconceptions about yeast swirl through the medical community too. One study suggests that as many as 50 percent of cases of yeast may be misdiagnosed by practicing physicians.¹ Yeast infections are regarded by many clinicians as boring. They consider itching a trivial complaint not worth serious investigation. Many clinicians still believe that they can make the diagnosis without any special testing or even seeing the patient. Even when an earnest effort is made, yeast can elude diagnosis if a woman is seen at a time when she's not having symptoms or after she has used antiyeast medication. Failing to recognize the complexity of a yeast infection may lead to undertreatment and recurrence, or to the conclusion that something more serious is going on. Perhaps most damaging is the attitude that we clinicians already know everything about this grand pest. Far from it! Most clinicians are not familiar, for example, with new information that yeast is not a single condition but a spectrum of disease, ranging from the isolated episode to unrelenting recurrence.
While yeast can indeed be a simple problem, it's also often complex, showing up in many different ways. There are some women who never have a yeast infection, or experience only one or two during their lives. Other women experience yeast only during a certain part of the menstrual cycle (cyclical candidiasis) but not at any other time. Still others have one infection after another and are unable to clear up the problem. Don't forget that many V problems can feel exactly like yeast: itchy skin diseases (Chapter 15), other kinds of vaginitis (Chapters 11, 12, 13), allergies (Chapter 14), and above all, that great masquerader, vulvodynia (Chapter 17). And if it isn't yeast in the first place, no yeast therapy is going to clear up the problem.
So where does this leave you when you suspect a yeast infection—besides miserable, that is? Before I chart the steps you should take, some background about yeast is in order. I know you're probably desperate for a remedy, but first we need to make sure that you're heading toward the right kind of remedy.
What is yeast?
When doctors say "yeast," we usually mean a fungus named Candida albicans. Yeast is not limited to the V zone. It's common on the skin and can be found in the gastrointestinal tract anywhere from the mouth to the anus. Candida lives harmlessly in the vagina in as many as one in five healthy women of childbearing age without causing any symptoms.² Remember, all sorts of organisms normally dwell there, including such villainous-sounding bacteria as E. coli and group B strep. Their presence doesn't mean you have poor hygiene or are dirty. As a protective measure, Mother Nature set us up to have bacteria—and yeast—on the skin and on every mucous membrane in the body.
Yeast gets into the vagina mainly from the neighboring intestines by way of the anal area. How does this happen? Not just from wiping yourself in the wrong direction, as women have traditionally been taught. It's just that the anus is very close to the vagina. The yeast can sprint independently from one organ to the other, or be passed along by a menstrual pad as it's worn, or be transferred during receptive oral sex, meaning that the partner's mouth contains yeast and comes into contact with the vulva, vestibule, or vagina. So you can't always actively prevent it.
Most of the time, a healthy vaginal environment and the normal immune system probably keep the harmless yeast from overgrowing and causing vaginitis. One current theory about yeast infections that keep coming back is that the vaginal immune system somehow fails to police the yeast, allowing them to run amok.
Yeast lives in two different forms. It can be seen as a spore, a small round or oval shape, or as hyphae, elongated stems with the spores inside or budding on the ends. It's long been suggested that yeast can invade tissue and cause disease only in the hyphal form. Spores have been considered innocent bystanders until they are stimulated to grow into hyphae. But we now know that both forms can cause disease. Spores can be hard to see under a standard microscope, but hyphae are readily visible. So if you're complaining of itching and other symptoms and the clinician sees spores or hyphae under a microscope, it's assumed that yeast is the problem.
Like many living organisms, yeast feeds off glucose (a kind of sugar). Yeast can grow at any pH from extremely acidic (2.5) to highly alkaline (7.5), so that trying to prevent yeast infections by doing things to change the amount of acid in the vagina is not going to be helpful.³
To live and grow in the vagina, yeast also has to have estrogen around. Candida albicans has a protein on it that makes estrogen stick to it, and the cells of the vaginal lining have a protein that makes candida stick to it.⁴ In addition, estrogen directly stimulates candida to switch from the yeast form that hangs out in the vagina, the spores, to the form that invades the vaginal cells and causes symptoms, the hyphae.⁵ (I wish Mother Nature had hooked yeast to testosterone instead, don't you?) The estrogen-yeast connection explains a lot. It's why young girls prior to puberty don't have yeast infections and why postmenopausal women not on hormone replacement therapy seldom do. These individuals have very low levels of estrogen in their bodies. The estrogen-yeast relationship may also explain yeast infections that occur during the second half of the menstrual cycle (cyclical candidiasis). In a 28-day cycle, with day 1 being the day menstruation begins, day 14 is the time of ovulation. Estrogen is at high levels from day 13 to day 23, then declines steadily. Yeast often flares up with the high estrogen levels after ovulation, then backs off as menstruation begins and estrogen levels have dropped to their lowest. Finally, estrogen's link to yeast explains why women taking tamoxifen for breast cancer get recurrent yeast infections. Tamoxifen is a synthetic antiestrogen that is diverse and complex in its actions. It blocks estrogen in the breast, but it may act as an estrogen in the postmenopausal vagina.
Symptoms of a yeast infection
A yeast infection results when there's too much yeast. It overwhelms the vaginal defense system. Yeast infections are almost always (85 to 90 percent of the time) caused by Candida albicans, but there are more than two hundred different strains of candida. Sometimes when drugs have been used to wipe out the Candida albicans, different yeasts called non-albicans yeasts can increase and cause infection. The best known of these are Candida glabrata and Candida tropicalis. The yeast that makes bread rise, Saccharomycetes cerevisiae, can also cause vaginitis. (Though uncommon, there have been reports of tiny fragments of uncooked dough on the hands and under the nails of bakers being transferred during sexual activity.) The non-albicans yeasts are harder to treat because they require higher and longer dosing of the standard medicines used for yeast, or they do not respond at all. We don't have many alternative medications to treat non-albicans yeast.
In particular, C. glabrata has received attention lately because infections caused by it are on the rise. What's happening is that women are using so many OTC antifungals that although the simple C. albicans is getting wiped out, other, more resistant yeast forms are taking its place. (This is similar to the concern with overuse of common antibiotics.) C. glabrata tends to respond poorly to the main ingredient in antifungal creams (azoles) such as Monistat, Gyne-Lotrimin, or Femstat. This type of yeast is seen more frequently in diabetics. There's also a connection between C. glabrata and douching, and this kind of yeast is also often seen in combination with bacterial vaginosis, possibly because C. glabrata tolerates the alkaline pH associated with BV.⁶
No matter what the strain of yeast, severe itching and vaginal discharge are the classic complaints. Neither symptom is seen only with yeast, and neither is always associated with disease (itching has many causes, and so does discharge). But if yeast is going to give symptoms, the most frequent symptoms are vulvar itching and itching around the vaginal opening in the vestibule.
Most women expect to see a cottage-cheese-like discharge, but in fact vaginal discharge is not always present or is often minimal; even if it is profuse, it doesn't always have a telltale curdlike texture. This discharge may vary from watery to uniformly thick. Vaginal soreness, irritation, vulvar burning, pain with intercourse, and burning when the urine touches the vulva are common. Odor is not a usual complaint, though candida causes a yeasty smell for some women.
An exam performed by a clinician shows redness and swelling of the labia and vulva, often with little red pimples separate from the central redness. The cervix is normal; the vagina is red and inflamed. Sometimes clumps of discharge stick to the walls, or there may be minimal secretions. Symptoms are often worse in the week preceding the menstrual period; with the menstrual flow women often experience relief.
Yeast infections produce a spectrum of symptoms. In general, the more intense the itching and redness, the greater the number of yeast organisms present. For some women secretions predominate, with profuse discharge that sticks to the vaginal wall in thick white patches or white plaques. This is sometimes called vaginal thrush. For other women, a more inflammatory picture emerges: minimal discharge but extensive redness over the vulva into the groin folds and down around the anus. There are also variations on both pictures.
What causes yeast?
When are you most vulnerable to a yeast infection? Let's examine each of the widely believed risk factors summarized in the box on page 198 in more detail.
THE SEX LINK
Many young women have their first yeast infection shortly after becoming sexually active. Is it just coincidence? Actually, this may occur because seminal fluid has been shown to encourage the spore form of candida to grow into the hyphal stem form.⁷ The hyphal phase of candida growth has been suggested to be the more active phase for invasion of the vaginal wall by the yeast.⁸ Sperm may also prevent the vaginal policemen, the white blood cells, from adequately fighting off yeast.⁹
Yeast infection is not considered a sexually transmitted disease. But there is a strong association between yeast and other STDs, such as chlamydia. So yeast is considered sexually associated.
In cases where the woman has repeated yeast infections, especially just after sex, a culture of the man's ejaculate may be helpful. This can be done at home after intercourse (the man should use a condom to collect the ejaculate). Alternatively, the man can produce an ejaculate in a container. A cotton swab is dipped into the semen in the condom and then placed in yeast culture broth the woman has been given at the clinician's office. She can return the culture the next day. Culturing the penis will not give helpful information, since it is the seminal vesicles where the yeast may reside. If a man has yeast in the seminal vesicles, he will not have any symptoms but he will need oral treatment to clear the yeast.
THE DIET LINK
Various things that women eat have been accused of causing yeast infections. Unfortunately, the research is just too thin to convince me that this is a solid risk factor. Sugar has been the chief suspect because yeast, like many living things, needs glucose or other simple sugars in order to function. It breaks glucose down to carbon dioxide and alcohol in a process known as fermentation. It's the alcohol produced by this fermentation process in the vagina that produces the burning sensation women experience with yeast infection. Sugar in the human body comes in many forms. The best-known sugars are complex, meaning that the body can break them down into simple forms. (You can tell a sugar because its name has the suffix -ose.) We eat several complex sugars: sucrose (table sugar), lactose (found in dairy products such as milk, yogurt, cheese, and ice cream), and fructose (from fruit). These complex sugars are broken down into building blocks that the body can use, such as glucose. Different kinds of yeasts are identified in the laboratory by the sugar they ferment: Candida albicans works on glucose, another strain of candida ferments mannose, and so forth. There is good evidence that a type of sugar (fucose) found in vaginal cells provides an attachment area for the yeast to hook on to.¹⁰
The notion of a sugar-yeast link started when researchers concluded that diabetes was a predisposing factor for yeast infection.¹¹ This is true. We now know that diabetics are more frequently colonized by yeast than nondiabetic women—however, most diabetics do not have repeated yeast infections.¹² Still, sugar connections were searched for because work in the laboratory suggested that yeast was more aggressive in response to the availability of sugar.¹³ Recommendations of dietary dos and don'ts mushroomed. To date, however, there is only one nutritional study on women with culture-proven yeast infections. It was done by a New England expert on yeast vaginitis. He found increased levels of three kinds of sugar (glucose, arabinose, and ribose) in the urine of women with recurrent yeast infections. Dietary patterns associated with these urinary sugars were a high intake of table sugar (sucrose) or sugar-rich foods, milk (more than a quart per day), cottage cheese, yogurt, and artificial sweeteners that contain milk sugar (lactose). In that study, eliminating excessive consumption of these foods brought a dramatic reduction in the incidence and severity of yeast infections.¹⁴ We just don't know enough, though, to make any blanket recommendations.
A diet eliminating carbohydrates and many other foods is recommended in the best-selling book The Yeast Connection, which has become something of a bible for women plagued by recurrent yeast infections.¹⁵ I'm skeptical of this too, however, because the author cites one study showing a positive relationship between Candida albicans and baker's yeast but offers no further scientific evidence other than conversations with physicians.¹⁶
On the basis of such limited evidence, all I am willing to say about diet and yeast infections is that overdosing on sugar may be a risk factor. Ordinary consumption of sweets is unlikely to trigger vaginitis. Large, well-run studies are needed to find out the truth about sugar and all the other carbohydrates before we can recommend therapies that really work.
Best advice: Eat a healthy, well-balanced diet. Make sweets a special treat. If you follow the food pyramid, you'll automatically consume a wise amount of sugar and sugar-containing foods, as well as consume dairy products in healthful moderation.
THE ANTIBIOTIC LINK
Yeast infections are often seen during or after treatment with oral antibiotics.¹⁷ In fact, the widespread use of antibiotics is the most probable explanation for the emergence of yeast vaginitis as a widespread problem.¹⁸ While any antibiotic can cause yeast to overgrow in the vagina, antibiotics that kill a wide variety of bacteria (called broad-spectrum antibiotics), such as tetracycline, are the worst offenders. The longer antibiotics are used, the more likely a yeast infection will result.¹⁹ Why is this so? Antibiotics wipe out the normal bacteria that live in the vagina; researchers suspect that these bacteria, especially the lactobacilli, protect by providing a roadblock that prevents yeast from growing and invading the vaginal wall.
If you are a woman with a history of repeated yeast infections, look back over past prescriptions to see if a course of antibiotics started them off. If you do have yeast that seems to occur after antibiotic use, or if you have frequent yeast infections, you need to talk with your clinician about preventative measures, such as using a tube of antiyeast cream with the antibiotic. Better yet, reconsider your use of antibiotics. They are not always as necessary as believed. Many people, for example, take antibiotics before dental work because of mitral valve prolapse, a minor abnormality of one of the heart valves that can increase the chance of infection of the valve; however, the American Cardiology Society has recently indicated that antibiotics are not necessary unless an ultrasound study of the heart shows significant leaking of the mitral valve. Antibiotics are also often taken for sinusitis when conditions other than bacteria are causing the symptoms. Antibiotics are of no value to treat the common cold, since it's a virus, not a bacterial infection. Make sure you need the antibiotics in the first place. Don't accept a prescription mutely without asking your doctor to describe the medication in detail.
THE CLOTHING LINK
Tight, poorly ventilated, and synthetic underclothing—all of which raise the temperature in the genital area and increase trapped moisture—are factors widely believed to contribute to recurrent yeast infections. Yet once again, little scientific data supports this belief. In a study of yeast infections among U.S. college women, no increased risk for yeast was found among women who wore tight clothing or noncotton underwear.²⁰ It's possible that contact with chemicals or allergic reactions may alter the vaginal environment and permit yeast to overgrow, but the study of college women did not identify any feminine hygiene practice as a risk factor for yeast infection. (There are other risks to this type of clothing, of course, as described in Chapter 5, "V Smarts.")
THE PREGNANCY LINK
One of the most enduring beliefs about yeast infections is that pregnant women are more susceptible to them. I'm not so sure. Some studies support this idea, having found more yeast colonization and more vaginitis, especially in the last trimester.²¹ On the other hand, studies also have found that the risk of yeast infections in pregnant women does not differ from the risk in other women.²² Many women make it through pregnancy completely yeast-free. Also, many vaginal problems in pregnancy that are attributed to yeast may be coming from other sources: bubble bath, harsh soap, hot water, thong underwear, BV, skin diseases, vulvodynia, and so on. For pregnant women, as with all women, yeast is often the only V descriptor they know to assign to any V condition.
Yeast infections may be harder to cure during pregnancy because high hormone levels at this time increase the starch content of vaginal cells, providing good nutrients for yeast. Estrogen also helps yeast attach better to the vaginal cell and then turn into a hypha (stem) form that can cause vaginitis.²³ Because vaginitis symptoms can be caused by things other than yeast during pregnancy, it's best not to self-treat with over-the-counter products. Check with your obstetrician or midwife first.
THE CONTRACEPTIVE LINK
Over the years reports about the relation of the birth control pill to yeast infection have varied. The older, high-estrogen pills (containing 50 or more mcg of the estrogen ingredient) thought to have promoted yeast are no longer recommended. The prevailing opinion had been that today's more common low-dose estrogen pills (20 to 35 mcg of estrogen) do not increase yeast infections.²⁴ Then two recent well-designed studies looking at women with culture-proven yeast infections showed a significantly higher risk of yeast infections in those who use low-dose oral contraceptives.²⁵
If you take oral contraceptives and have repeated episodes of yeast infection that have not responded to treatments, a "trial-of-one" therapy, in which your doctor monitors you for candida infection while on and off birth control pills, is a plan you might want to consider.²⁶ Be sure to use another reliable means of birth control. No one has studied the effect of discontinuing the pill for women who have repeated yeast infections.
The intrauterine device (IUD) is also associated with increased risk of yeast infections. If you have repeated proven yeast infections with an IUD, talk with your clinician about another form of birth control. The diaphragm can increase the number of yeast that live in the vagina, but it is not associated with an increased rate of infections.
OTHER LESS WELL KNOWN LINKS
Immunosuppression and Yeast
People who have to take systemic cortisone, such as those with severe asthma, rheumatoid arthritis, and many chronic diseases such as lupus and MS, are at increased risk for yeast infections. A question about the relationship of HIV to frequent recurrent yeast vaginitis has been raised, but this has been nothing more than a scare. While both men and women with HIV are susceptible to resistant oral yeast infections, no good studies have shown that women with HIV are particularly prone to recurrent vulvovaginal yeast.²⁷
Genetics and Yeast
This may turn out to be one of the most important explanations for women who get one yeast infection after another. Blood group characteristics are related to a woman's susceptibility to yeast infections. Besides the common A, B, and O groups, there can be other proteins (called factors) on red blood cells with different names, such as Kell, Duffy, and Lewis. (So, for example, you can be blood type A positive and also have the Kell factor.) Women who have the Lewis factor are three to four times more likely than the general female population to have recurrent yeast infections.²⁸ This means that up to 25 to 33 percent of patients with recurrent yeast infections are genetically predisposed to developing the problem, probably because along with inheriting the Lewis blood protein, they also inherited a vaginal immune system that doesn't fight off yeast the way it should. This would explain how you can be perfectly healthy, do everything right, avoid all the known risk factors, and still have yeast problems! Unfortunately, it's still only a theory; no targeted treatments exist yet.
Allergy and Yeast
Mounting evidence supports the yeast-as-allergy theory, in which yeast swamps a previously healthy immune system. Many women with recurrentvulvovaginitis have an immune system that doesn't respond during a particularly bad yeast infection.²⁹ Some of their white blood cells have a reduced ability to multiply and fight in response to Candida albicans (a condition called reduced lymphocyte proliferative response).³⁰ In response, these women also produce a compound that suppresses the immune system, prostaglandin E2.³¹
Here's how yeast allergy might work in a woman's body. During the first yeast infection, the yeast invades the top layers of the vagina and grows inside the vaginal cells. There, deep in the cells, the yeast is somewhat protected from the antiyeast cream and the immune system. Yeast proteins, called antigens, that the body recognizes as foreign are released from the cells and cause the production of antibodies, substances to fight off the foreigners. The antibodies in turn trigger the release of histamine, which not only produces itching and burning but also keeps the elements of the immune system from fighting back—white cells cannot multiply and move into the area. Thus, the vaginal defenses are paralyzed, and yeast takes over. To add insult to injury, now that the vaginal immune response is wiped out, any chemical or foreign protein coming into contact with the vagina at this point can set off an allergic reaction that causes the cells to swell and rupture, releasing the yeast inside. The whole cycle begins again. The theory of this self-perpetuating cycle, developed by Marjorie Crandall, is shown below in diagram form on page 207.³²
If recurrent yeast infection represents an allergy, then would allergy shots against yeast work? Over the years several studies have reported success.³³ I have just finished a small pilot study on yeast-allergy shots. Five of ten women had improvement, but these numbers are too small for statistical significance. As always, we need more work.
Diagnosing a yeast infection
If you see a doctor or nurse-practitioner because you think you might have a yeast infection, you absolutely need a complete workup. Chapter 9 outlines these steps: a history, a pelvic examination, a pH test, a wet prep, and a whiff test.
A yeast infection is, in many cases, identified by performing an examination of the vaginal discharge under a microscope to detect the presence of yeast stems (hyphae). If hyphae are seen, the diagnosis is plain, and often no further testing needs to be done if the pH and whiff tests are normal. (If these tests are abnormal, there is probably a mixed infection, with trichomonas or bacterial vaginosis present as well.)
Yeast cultures are not needed in cases of uncomplicated yeast where hyphae have been seen under the microscope. There are, however, several situations that require a yeast culture:
A woman has symptoms of itching, burning, and discharge, but no spores or hyphae are seen under the microscope.
The clinician sees only yeast spores (not hyphae) under the microscope, suggesting infection with a non-albicans yeast that is resistant to some therapies.
The clinician sees many white blood cells under the microscope but cannot find any yeast or trichomonads.
The woman has used standard treatments for yeast and her symptoms have not improved.
The clinician wishes to treat the woman with months of oral antifungal therapy for recurrent yeast.

Remember (from Chapter 9) that a yeast culture is done on a special medium called Sabouraud's medium; this is different from a vaginal culture for bacteria. Routine bacterial cultures are seldom helpful because they grow a lot of bacteria that are normally found in the vagina: strep, staph, gardnerella, and E. coli.
Remember too that simply looking through the vaginal speculum at the vaginal discharge to diagnose yeast is outdated and inaccurate. Be sure you find a clinician who does a complete exam and is willing to use the yeast culture on Sabouraud's medium as a backup.
There are a number of reasons why yeast may not be seen under the microscope or in a yeast culture:
Microscopy is only about 40 percent accurate.
A woman has been partially treated by using an antifungal cream or taking a Diflucan tablet within a few days of the visit.
The checkup occurs at a time when the woman is not having symptoms.
Yeast is not the cause of the problem; most vulvovaginal problems cause itching and burning. Trying to arrange an appointment at the time of symptoms can be difficult. Many physicians work with nurse-practitioners, who may have more availability for appointments. If you have the kind of yeast that flares in a cyclic fashion, explain this in order to schedule at the right time.

Self-diagnosing a yeast infection
But wait, you're thinking. What about those handy tubes of antiyeast cream that I can buy at the supermarket? As you can see, yeast is a complicated problem. Without previous diagnosis in a clinical setting or a thorough education about the many faces of yeast, attempts at self-diagnosis will likely be inaccurate and will lead to ineffective self-medication. Even when a woman is completely familiar with yeast symptoms and has been treated by a clinician for a prior episode, an accurate diagnosis may still require a vaginal examination, pH determination, yeast culture, and microscopic evaluation of vaginal secretions.
Nevertheless, in 1990, the FDA approved the OTC availability of antifungal products. They're sold under brand names such as Monistat, Gyne-Lotrimin, and Femstat. Almost immediately, sales of these agents went through the roof, from nine million units per year as prescription drugs to twenty-four million units per year as OTC medications. More than $600 million in sales was recorded in 2000.³⁴ Clearly, women love the convenience and sense of control that these products provide. And I'll be the first to acknowledge that a quick fix is terrific—when it is the right one. Unfortunately, this is often not the case. The FDA allowed OTC antifungal products based on research that is misleading when applied to the overall population of women who may self-diagnose and self-medicate. The women in the studies reviewed by the FDA were prone to yeast infections but had been carefully educated about the symptoms of other vulvovaginal conditions. Almost two-thirds of them correctly self-diagnosed yeast infections based on their symptoms, compared with four-fifths of the clinicians in the study. When the test population was limited to women who had had a prior clinical diagnosis of yeast, four-fifths were able to diagnose their problems accurately.³⁵ The rub: This level of knowledge is not representative of the women who are using the products now.
Other studies have shown less impressive results. One found that although the majority of women thought yeast was the cause of their symptoms, only about a quarter of them were correct. Instead, bacterial vaginosis, vulvar vestibulitis, and irritant dermatitis were their problems in almost half of those cases.³⁶ In another study, only 11 percent of women who did not have a prior diagnosis of yeast were able to self-diagnose correctly. Of women who had previously been diagnosed with yeast, the rate of accuracy increased, but only to 34.5 percent.³⁷
You can see why vulvar disease experts, including me, were aghast when the FDA approved OTC cream. Obviously it's difficult for women to figure out what's behind their vulvovaginal symptoms. As a result, over-the-counter products are being used inappropriately part of the time; women do not know about all the other conditions that may produce irritation, discharge, or itching. With self-misdiagnosis they experience prolonged discomfort or complications associated with their complaint. Millions of dollars are wasted by women trying to treat lichen sclerosus, vulvodynia, precancerous skin changes, and chlamydia with antifungal cream. Some of the complications may be serious if an STD or pelvic infection is missed, or if a urinary tract infection worsens, or if an inflammatory skin disease goes undetected. Remember, even professional medical people may find the diagnosis of yeast challenging.
So what's a woman to do when she needs help? I hope that highly accurate home tests for diagnosis will be available soon. In the meantime, women need to be educated not to rely on clinicians who diagnose over the phone, without doing an exam, or by looking through the speculum only. Women need to find a clinician who does basic simple tests: exam, pH, wet prep, and whiff test. Remember, if itching is present and yeast is not seen under the microscope, then a yeast culture on Sabouraud's medium is important.
Yes, self-treatment is faster and less expensive than making a doctor's appointment. That's why women like it. Unfortunately, it's just not the right course of action as often as most women would like it to be.
A yeast infection action plan
If you are having V symptoms that you think are an isolated or occasional yeast infection, here is an approach:
First, don't be hasty. Don't assume all V symptoms are a yeast infection. Don't automatically purchase OTC cream for an itch. Review Chapter 7, "The Most Bothersome Symptoms," to see if anything else fits.
See a clinician if this is your first episode of persistent V symptoms, you are pregnant, you are 13 years old or younger, you have had more than three episodes this year, you have diabetes or HIV, or you take cortisone by mouth.
Choose an OTC antifungal cream for yeast if you have had prior yeast infections clearly diagnosed by a clinician and if you got prompt, total, and lasting relief from antiyeast cream. Yeast is easy to cure in most cases; symptoms that persist may not be yeast.
If you use an OTC product and your symptoms do not improve in three days or are not gone in seven, see a clinician. Don't bother trying another brand or strength. Choose your care provider carefully; many will merely hand out more cream. You need someone who will check for other kinds of vaginitis, do a culture for resistant yeast, and evaluate for skin diseases and vulvodynia.

Steps to controlling recurrent yeast
Get confirmation. If you think you have repeated yeast infections, it is essential to confirm this by being seen by a clinician at the time the symptoms flare to prove this is yeast. Just because you have had several episodes of yeast in the past year does not necessarily mean your current itching represents another yeast infection. You might be reacting to the ingredients in all the antiyeast creams you have used. Or maybe you are irritated from wearing a panty liner every day. You need proof that you have yeast, and you need identification of the species of yeast that you have.
Reduce the risk factors. If you have repeated yeast infections, eliminate factors that are known to contribute to yeast. Controlling blood sugar in a diabetic, eliminating antibiotics, or bringing a chronic skin condition under control are examples of areas that may need work. But remember that sometimes there are no risk factors at fault; yeast may come because the vaginal police are off duty for some unknown reason.
Look at your diet. The only scientific nutritional study done in women with proven yeast infection showed that many were drinking more than a quart of milk a day and more than a quart of sugary cola a day. That's too much! Eliminating sugar and dairy products is not realistic, but a normal balanced diet will put both of those elements under control and is recommended for every part of your health and well-being.
Consider checking your partner. This is possible by obtaining the yeast culture medium from your clinician, and by placing a cotton swab dipped in your partner's ejaculate into the culture broth (see page 198). You then bring it to the clinician for examination. Eliminate oral sex, or have your partner's mouth and throat cultured for yeast. If you have multiple partners and frequent sex, you may need to work with medication to control yeast.
If all else fails, move on to suppressive medications. If you've worked with diet and lifestyle changes and you're still having yeast—and you're sure that it's yeast—you'll need to work with suppressive medications.

Early treatment for yeast infection utilized Nystatin; while still available and still used, Nystatin has been largely overtaken by a generally more effective family of creams and suppositories, the azoles, so called because they all have a similar molecular design. The azoles include butoconazole (Femstat), clotrimazole (Gyne-Lotrimin), miconazole (Monistat-3, Monistat-7), econazole, fenticonazole, and tioconazole (Monistat-1). Recently that design was redone, producing terconazole (Terazol), reported to be more effective. Finally, in the 1980s and 1990s we started to have oral medications against yeast: ketoconazole (Nizoral), fluconazole (Diflucan), and itraconazole (Sporanox).
The azoles need high doses and extended treatment to eradicate Candida glabrata or other non-albicans species. These yeasts have changed themselves (mutated) so that they respond poorly to the azoles. The triazole Terazol is effective against non-albicans yeast.
Treatment for uncomplicated yeast can be either topical, by cream or suppository, or single-dose oral therapy. All of the treatments work against the standard cause of yeast infection, Candida albicans. Drug resistance of albicans yeast is extremely rare, with only two or three cases recorded in the world.³⁸ If symptoms do not improve, a yeast culture becomes vital, because the non-albicans yeast, such as Candida glabrata or Candida tropicalis, usually will not respond to the standard treatment length.
Complicated yeast
Women with complicated yeast infections need a longer course of therapy no matter how the medication is given. Conventional five- and seven-day therapy should be increased to ten to fourteen days to achieve no more symptoms and negative culture. More than one dose of oral Diflucan is needed. The initial outbreak is controlled with 150 mg of Diflucan every other day for three doses, followed by one tablet weekly for a few weeks to suppress yeast and keep it out of the picture. For women with yeast that has recurred for years, the suppression may be safely continued for up to six months. The earlier oral antifungal drugs such as ketoconazole had the risk of possible liver damage and required careful monitoring of liver function. Fortunately Diflucan, given in weekly doses, appears safe and does not require liver monitoring.
When the vulva is severely inflamed, women need special consideration. The usual creams may not be enough and may, in fact, make the burning worse. The oral medications fail to provide immediate relief. Such patients need to start oral antifungals and pursue a variety of additional remedies: sitz baths, cool compresses or ice, low-potency hydrocortisone ointment. Oral Diflucan can take three to seven days to bring complete relief.
Dealing with a resistant yeast such as Candida glabrata can be frustrating for both patient and clinician. Some infections can take months to respond to treatment. Studies show that most non-albicans yeast will respond to conventional therapy with azoles provided that the treatment is given an adequate length of time.³⁹ One to two weeks of oral and topical azole therapy—Diflucan combined with Gyne-Lotrimin, for example—is the first step. If azole therapy fails, as is often the case, the next step is to use boric acid.
Boric acid is an agent that has been around since the days of the pharaohs. Little has been written about it for the treatment of yeast infections, probably because we have many effective modern antifungal agents. Yet boric acid is a very effective antifungal, particularly in the treatment of non-albicans yeast such as C. glabrata, where it cured about 70 percent of women in one study.⁴⁰ In another study boric acid was effective in curing 98 percent of the patients with culture-proven yeast infections that had failed to respond to the most commonly used antifungal agents.⁴¹ Boric acid 600 mg capsules are inserted vaginally one or two times daily for fourteen days. These capsules have to be made up by a pharmacist. With this dose, systemic absorption of boric acid from the vagina is minimal, but compliance is a drawback with the two-week treatment period.⁴²
Boric acid has to be used as directed. It is not to be taken by mouth; the capsules must be kept out of reach of children. Its safety in pregnancy has not been studied, and so its use in pregnancy is not recommended. High dosages can lead to severe burns. It is absorbed through damaged skin and wounds but does not penetrate intact skin. When used vaginally, it stays there and does not travel through the body.⁴³ When boric acid fails, flucytosine (Ancobon) cream or amphotericin cream may be used for a fourteen-day regimen. These are antifungals that are not commonly used, so they have to be made up by a special compounding pharmacy. When all else has failed against Candida glabrata, terbinafine (Lamisil), a new drug out for the treatment of the fungus that invades nails, is occasionally used; it may work, not because it is a great treatment for C. glabrata but because it is a new molecular structure that the yeast has not yet encountered.
Prolonged use of azole creams or Diflucan in daily doses over a period of weeks has an unfortunate side effect. Candida glabrata and other yeast can develop in a situation where all the standard albicans yeast has been eliminated by azole therapy, leaving the resistant forms to overgrow. Here is another important reason to be sure that the problem is yeast before taking these medications: Week after week of using an antifungal cream or popping a Diflucan every few days brings the risk of developing a persistent yeast infection that can take months and months of therapy to treat.
Finally, yeast-allergy shots (immunotherapy) have been used to treat difficult recurrent yeast with significant reduction in the number of relapses.⁴⁴ Weekly injections of candida extract are given for a year, with maintenance booster shots afterward. This is a therapy that is still not widely studied but has potential. You or your gynecologist would need to find an allergist to administer the injections.
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