Bacteria for Vaginal Health: Truth or Myth?

Τhere are some basic things that are good to know about the “bacteria for sale” on pharmacy shelves.

Probiotics are live microorganisms, promoted by pharmaceutical companies, claiming that when administered in adequate amounts result in a health benefit on the body by restoring, boosting or improving the gut and vaginal flora.

The scientific community claims that the microflora should maintain an equilibrium between the populations of beneficial and potentially harmful bacteria. The equilibrium of this ecosystem can be altered very often in people with a female reproductive system, and as a result they are forced to seek solutions, via food or drugstore supplements.

What are the criteria for selecting the best drugstore product?

What are the official guidelines from the scientific community?

The role of supplements that contain probiotics is to re-establish microflora mostly in the vagina, gut and skin. When it comes to the vaginal microbiome, its balance is disturbed from many conditions including infections (bacterial vaginosisvulvovaginal candidiasis), pharmacotherapy (antibiotics, hormonal therapy), diabetes, menstruation, perimenopause, menopause, pregnancy, and hormonal fluctuations due to psychological factors (e.g. stress).

The above conditions are quite common, and because of the theoretical benefits deriving from the increase in the number of healthy vaginal bacteria, there is a tendency to present probiotics as an appealing health promotion method. As a result, many patients have high expectations from a probiotic supplement, as they seek immediate relief, a natural treatment without side effects, a long-term balance of the vaginal flora and a reduction in the recurrence of vaginal discomfort.

As a result, like all good bacteria, probiotics have sprung forth and multiplied. Trillions live in our guts, and even more have begun to occupy drugstore shelves.

But we know so little about them:

1.Under which conditions were they cultured, packaged, transported and stored until the final recipient, the consumer? Probiotics are by definition alive and required to have an efficacious amount of viable bacteria at the time of administration to the host, but most probiotic preparations, especially at the end of shelf life, will also include potentially large numbers of dead and injured microorganisms. So, the creation of certified laboratories where the quality control of probiotics should be performed using universally shared validated and standardized methodologies is important.

Since 2021 there is a European legal framework for medical devices (which have stricter marketing conditions than a simple dietary supplement) and probiotic preparations are subject to a new, more controlled and more unanimous legal regime. Such a legislative change will make the probiotic sector more credible to both the scientific community and the consumer. Therefore, food such as yogurt cannot be compared as a source of controlled levels of probiotics and cannot be a substitute for a medical device, as the conditions of production, storage and transport are more unstable (e.g. refrigerated).

2.Product description: The titles on the packages consist of impressive numbers of bacterial strains with even more impressive Latin names that we know little about their role. The strain with the most extensive list of studies for vaginal disorders is the species Lactobacillus, whose role is to help maintain the pH of the vagina. Therefore, it is a good selection criterion.

3.Route of administration (oral, vaginal): the scientific community has not yet answered which is the ideal route of administration. Most scientists are concerned about taking it orally, as it is not easy to calculate what percentage of the ingested bacteria contained in the capsule succeed in reaching the rectum, ascending the vagina, and dislodging bacterial pathogens and yeasting the vaginal area. Due to the above limitations, the scientific community encourages the intravaginal application of suppositories with the bacterium Lactobacillus acidophilus, which seems to have the best characteristics of intravaginal colonization.

4.Time of use: will the medication I take or the food I eat affect the absorption of my probiotic supplement? First of all, the instructions of the manufacturerI should be carefully read. A more general advice is that Lactobacilli can be inhibited by antibiotics and should be taken at least 2–4 h after the antibiotic dose. They should be taken with food because the increased gastric pH is more favorable for the probiotics.

5.Is the health benefit long-term? Scientific studies show that probiotics, when taken with pharmacotherapy for a specific reason (e.g. antifungal therapy for candidiasis) may help in the eradication of the problem, but they do not contribute to a general maintenance of the healthy vaginal flora. When it comes to antibiotics, probiotics are often prescribed for 1–3 weeks longer than the duration of antibiotic treatment. Re-introducing physiologic bacteria after pharmacological eradication of pathogens seems rational, but in most cases, it would result in trying to cure the consequence rather than the origin of the disorder and should seek further clinical evaluation.


1. The journey of probiotics from the mouth to the vagina is not as clear as most medications. Scientists do not have a unanimous agreement about taking probiotics and their ability to improve vaginal hygiene.

2.In the coming years, due to the new legal framework, probiotic preparations will be released with much better-quality guarantees. Your doctor and your pharmacist are the best consultants.

3.If the medication one takes has vaginal as well as intestinal side effects, it is preferred to take oral probiotics, in combination with a vaginal suppository. Otherwise, if one is more concerned with the vaginal microflora, a vaginal suppository, ideally with Lactobaccilius acidophillus is best.

4.It is important to read carefully and abide by the instructions provided by the manufacturer, regarding the method of storage and dosage.

5.Media sources tend to present probiotics as an appealing health promotion method able to prevent or treat a wide variety of clinical conditions. If you notice frequent recurrences or prolongation of symptoms, it is best to consult a doctor you trust.

Do not forget: the female reproductive system is a dynamic system, with its changes, its fluctuations, its differences in odor, fluids and other signs, which we should respect, love and observe. Abuse of vaginal douches and cleaning products is not a solution. The health professional whom you trust, is the best consultant in times of need.

Words by: Aspa Theochari, Pharmacist

Gynecology 101: The abc's of sexual health.​

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