Why Do Antibiotics Cause Yeast Infections?

Why Do Antibiotics Cause Yeast Infections?


Taking antibiotics can cause vaginal yeast infections. It’s because while killing the bacteria that cause infection in your body, they also change the vaginal pH to less acidic, killing the friendly bacteria which help prevent vaginal yeast infections and bacterial vaginosis.


Why do antibiotics cause yeast infections


Antibiotics can also contribute to the formation of Candida species resistant to common antifungal medication, such as Candida galbrata. Some antibiotics have been shown to be more yeast infection inducing than others:


  • According to a study from 2001 Ampicillin and Ceftriaxone promote colonization with Candida, and some new studies show that it can have a long-term effect on human microflora, after finishing treatment.


  • Another study shows that Amoxicillin and Erythromycin are also likely contributors to Candida overgrowth


  • A study conducted on mice in 2005 shows that Cefepime, Levofloxacin, and Aztreonam are much less likely to promote Candida growth than Piperacillin-tazobactam, Ceftriaxone, Metronidazole, and Clindamycin.


Why Do Antibiotics Cause Yeast Infections


  • Another study shows that Carbapenems, Trimethoprim-sulfamethoxazole, Clindamycin, and Colistin contribute to the growth of fluconazole-resistant Candida species, which are more difficult to treat than Candida albicans.


  • Although it was believed that Tetracycline can trigger vaginal candidiasis, recent studies show that it’s got little effect on Candida growth.


Based on this research, I came up with a list of the antibiotics you should try to avoid and those that seem safer in terms of Candida colonization. Discuss with your doctor which antibiotics would be best for you and if it’s possible to switch to a safer alternative (it may not always be possible).


Antibiotics that can cause a yeast infection (with their brand names in brackets):





Trimethoprim-sulfamethoxazole (Baktrim, Sulfatrim)


Clindamycin (Cleocin HCl, Cleocin Pediatric, Cleocin Phosphate)


Colistin (Coly-mycin M.)


Piperacillin-tazobactam (Zosyn)


Ceftriaxone (Rocephin)


Metronidazole (Flagyl, Metryl, Protostat)



Amoxicillin (Amoxil, Amoxicot, Biomox, Dispermox, Moxatag, Moxilin, Trimox, Wymox)


Erythromycin (E.E.S. Granules, EryPed 200,  Ery-Tab, Erythrocin Stearate Filmtab, PCE Dispertab)


Ampicillin (Principen)


Ciprofloxacin (Cipro)



Why Do Antibiotics Cause Yeast Infections- (1)

‘Safe’ antibiotics:



Cefepime (Maxipime)


Levofloxacin (Levaquin)


Aztreonam (Azactam)


Tetracycline (Ala-Tet, Panmycin, Sumycin)



How to Avoid a Vaginal Yeast Infection While on Antibiotics?


If you want to avoid getting a vaginal yeast infection while on antibiotic treatment, make sure you try to replenish the good bacteria in your body. You can do it in three ways:



  • Insert a probiotic suppository overnight for the duration of your treatment and at least a week after you finish taking antibiotics. Take a look at my reviews of probiotic suppositories.


  • Use probiotic tampons during your period to strengthen your vaginal flora when it’s most vulnerable to infection.


Other things you can do to prevent a vaginal yeast infection while on antibiotics are:


  • Ask your doctor to prescribe you an oral antifungal pill, such as Fluconazole, once a week during your treatment as a preventive measure. You could also be advised to use antifungal suppositories during your antibiotic treatment, especially if you suffer from recurrent vaginal yeast infections. Make sure you discuss it with your doctor.








It’s worth to think twice and consider other options before taking antibiotics and only take them when absolutely necessary. According to the National Institute for Health and Care Excellence, in England alone, one in four antibiotic prescriptions are issued unnecessarily.


Why Do Antibiotics Cause Yeast Infections



Antibiotics can seriously affect your bacterial flora, leading not only to all sorts of yeast infections, but also IBS (Irritable Bowel Syndrome) and antibiotic resistance in future. While on antibiotics, follow the advice above and hopefully, you’ll be able to avoid a vaginal yeast infection.


Please share your experiences and tips in the comment section below.


  • I find it very frustrating to have to take antibiotics and then take more medication to prevent a yeast infection.
    This past year I had to see my ob/gyn two times and was treated for BV with antibiotics and was told to take an oral pill after to prevent/cure any yeast infection that may occur. I don’t like the fact that taking one medication starts another infection…..
    I would like to avoid antibiotic but if that’s the only course of action for a solution, what can you do?
    I like your preventative measures and will be sure to take those steps as to avoid a yeast infection. In your experience, which has been the most effective in avoiding a yeast infection after taking antibiotics, supplements or suppositories? Or do you use both at the same time?

    • Thanks for your comment Dinh. To be honest, I used only probiotic suppositories and sometimes that would be enough, but sometimes it wouldn’t. I think your best bet it to use both, as well as one Fluconazole pill during your antibiotic treatment, it’s a very effective oral antifungal medication.

  • The information that you provide is so important. I have taken a lot of antibiotics in my life and usually get a yeast infection from them. When prescribed antibiotics, I would always ask for a 2nd prescription for the yeast infection I knew I was sure to get. Much more information is known today about the bad stuff that can happen to our bodies from yeast. Thanks for this great post.

    • Thanks for your feedback Erin. Apart from taking antifungal medication to prevent a yeast infection while on antibiotics, it’s also worth to take a probiotic supplement to help your body reestablish its bacterial flora so it’s better prepared to fight all sorts of infections caused by yeast and harmful bacteria.

  • William "Nuggie" Nugent

    I just came across this article and I thought that I would leave a few of my thoughts.

    Let me say that I don’t think that this is where I belong, I am a guy. I am surprised, but not offended.

    I will also add I kept reading and I learned a few things. I had no idea about how women grt yeast infections.

    Overall, good job. Thanks for your thoughts.

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