Yeast Infection

What causes a yeast infection?

Our experts share what causes or increases yeast infection risk. Plus, how to treat a yeast infection treatment online with a virtual health assessment.
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Key Points:

  1. Yeast infections are caused by an overgrowth of Candida fungus. This can happen anywhere on the body but it often happens in the vagina.
  2. Anyone can get a vaginal yeast infection. But using antibiotics, periods of hormonal change and conditions like diabetes can increase yeast infection risk.
  3. Yeast infections are diagnosed by licensed medical providers through pelvic exams and samples taken from the infected area. Yeast infection prescription treatments include vaginal suppositories and oral medications.

Vaginal yeast infections can trigger uncomfortable vaginal itching and vaginal irritation. Without the right treatment, you may end up with a stubborn yeast infection that won’t go away.

If you’re wondering if stress can cause a yeast infection or worries that you may be getting a yeast infection before your period, we’ve got your back. Here’s what to know about the causes of vaginal yeast infections. Plus, how Dr. B can help you get a prescription vaginal yeast infection treatment online through a virtual consultation.

What is a yeast infection?

A yeast infection is a common fungal infection caused by an overgrowth of the Candida fungus. The Candida family of yeast naturally lives on the skin and inside the body. A yeast infection occurs when an imbalance of hormones causes it to grow unchecked. When this happens, uncomfortable symptoms can follow.

Common symptoms of a yeast infection in the vagina include:

  • Burning around the vagina
  • An itchy vagina or itchy vaginal lips
  • A thick, white vaginal discharge
  • Pain or soreness around the vagina
  • Redness or swelling of the vulva
  • Vaginal rash
  • Small cuts or cracks in the skin of the vulva
  • Pain or burning during intercourse or urination

These symptoms can be similar to other vaginal conditions. To find out which infection you have, seek a diagnosis from a medical provider.

What is the main cause of a yeast infection?

Candida is a family of yeast found naturally in small amounts on the skin and in areas like the throat and vagina. In most cases, Candida is harmless. But when the yeast overgrows, it can upset the healthy balance of bacteria and cause an infection.

Yeast infections can happen to anyone. Vaginal yeast infections are common, affecting up to 75% of people with vaginas at least once in their lifetime. But an overgrowth of Candida can also trigger symptoms on and around the penis.

Factors that can increase your risk of yeast infection include:

  • Hormonal changes that occur during pregnancy, breastfeeding or menopause
  • Taking birth control pills
  • Having uncontrolled diabetes
  • Using antibiotics that kill “good” bacteria in the vagina
  • Having a compromised or weak immune system
  • Using vaginal sprays and douches

Are yeast infections contagious?

It’s uncommon, but a yeast infection can be transmitted through vaginal, oral or anal sex.

Sexually active people with recurrent infections may wonder if sperm can cause a yeast infection. It is possible to have an allergic reaction to your partner’s semen. And sexual activity can disrupt the balance of bacteria in the vagina and lead to a yeast infection. But sperm (on its own) does not cause yeast infections.

People with penises can get yeast infections, too. This is most common when a partner already has a yeast infection. And it happens more often in those who are not circumcised.

Are yeast infections a sexually transmitted illness (STI)?

Yeast infections are not an STI. But they can share similar symptoms with STIs, including herpes and genital warts.

Because they share similar symptoms, you may worry that a yeast infection can cause a false positive herpes test result. But false positive results of herpes tests are not common. You can have both conditions at the same time. Seek help from a medical provider to find the proper treatment.

How is a yeast infection diagnosed?

To properly diagnose a yeast infection, a medical provider may:

  • Ask about your medical history. This includes your history of vaginal infections, risk factors like diabetes or medications like birth control pills and antibiotics.
  • Perform a pelvic exam. To check for signs of infection, your provider may examine your genital area by inserting a speculum into the vagina.
  • Take a sample of your vaginal discharge. Your provider may test a sample of vaginal fluid to identify the type of fungus causing the infection. This way, they can determine the best way to treat your yeast infection or another condition.

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How to treat a yeast infection online

Whether it’s your first or fifth infection, a vaginal suppository or pill for yeast infection can clear up symptoms fast. And Dr. B can help you get those prescription treatments online!

Just start an online health assessment. A licensed provider will review your treatment. If they determine that an online yeast infection prescription medication is appropriate, they’ll send it to your chosen local pharmacy.

Dr. B treats conditions across primary care, dermatology, sexual health and reproductive health. Paying patients pay only $15 per assessment. And we have a No-Cost Care program for those who qualify based on financial need. So don’t wait for relief. Get started today!


Centers for Disease Control and Prevention. (2013). Vulvovaginal Candidiasis (VVC).

Centers for Disease Control and Prevention. (2022). Genital herpes screening FAQ.

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