Imvexxy (estradiol) is a prescription drug that’s used to help treat painful sex after menopause. Imvexxy can cause side effects that range from mild to serious, such as headache.

The active ingredient in Imvexxy is estradiol. (An active ingredient is what makes a drug work.) The drug comes as a capsule that’s inserted into the vagina.

Keep reading to learn about the common, mild, and serious side effects that Imvexxy can cause. For a general overview of the drug, including details about its uses, see this article.

Some people may experience mild to serious side effects during their Imvexxy treatment.

Headache is an example of a commonly reported side effect of Imvexxy. To learn more about this side effect, see the “Side effects explained” section below.

Mild side effects have been reported with Imvexxy. These include:

In most cases, these side effects should be temporary. And some may be easily managed. But if you have symptoms that are ongoing or bothersome, talk with your doctor or pharmacist. And do not stop using Imvexxy unless your doctor recommends it.

Imvexxy may cause mild side effects other than those listed above. See the drug’s prescribing information for details.

* To learn more about this side effect, see the “Side effects explained” section below.
† An allergic reaction is possible after using Imvexxy, but this side effect wasn’t reported in studies.

Serious side effects have been reported with Imvexxy. These include:

If you develop serious side effects while using Imvexxy, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

* To learn more about this side effect, see the “Side effects explained” section below.
† An allergic reaction is possible after using Imvexxy, but this side effect wasn’t reported in studies.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Imvexxy, visit MedWatch.

Get answers to some frequently asked questions about Imvexxy’s side effects.

How long do side effects of Imvexxy usually last?

Studies of Imvexxy haven’t reported how long each side effect may last. For many drugs, side effects are temporary and will go away soon after you start or stop the drug.

But Imvexxy may raise the risk of certain side effects that cause long-term problems. This includes the risk of endometrial cancer, heart and blood vessel problems, dementia, and breast cancer.*

Talk with your doctor to learn more about possible side effects of Imvexxy and how long they may last.

* Imvexxy has boxed warnings about these risks. A boxed warning is the most serious warning from the FDA. To learn more, see the “Side effects explained” section below.

Can Imvexxy cause hair loss?

It’s unlikely. Hair loss wasn’t reported as a side effect in studies of Imvexxy.

But menopause may cause hair loss. Imvexxy is used to treat painful sex after menopause. So you may notice hair loss related to menopause while using the drug.

If you have other questions about Imvexxy and hair loss, talk with your doctor or pharmacist.

Learn more about some of the side effects Imvexxy may cause.

Boxed warnings

Imvexxy has boxed warnings for the following risks. A boxed warning is the most serious warning from the FDA.

These side effects weren’t specifically reported in studies of Imvexxy. But these are known risks of estrogen therapy in certain situations. (The active ingredient in Imvexxy is estradiol, which is a type of estrogen.)

Risk of endometrial cancer

Endometrial cancer is a type of cancer that starts in the lining of your uterus. This condition may cause symptoms such as:

Due to this risk, doctors typically won’t prescribe Imvexxy for people with unusual genital bleeding that doesn’t have a known cause.

What might help

Your doctor may recommend having routine pelvic exams during Imvexxy treatment. These exams could help identify signs of endometrial cancer.

If you have any symptoms of endometrial cancer, tell your doctor right away. They’ll likely order tests to check for this condition.

Risk of heart and blood vessel problems

Examples of heart and blood vessel problems include stroke and blood clots in a deep vein. Symptoms of stroke may include slurred speech and weakness or numbness on one side of the body. Blood clots may cause symptoms such as pain, tenderness, or warmth around the affected area.

Having a stroke, heart attack, or blood clots in the past could raise the risk of heart and blood vessel problems. Other factors that may increase this risk include:

What might help

Your doctor will advise you on your risk of heart and blood vessel problems during Imvexxy treatment. If you have symptoms of a blood clot during treatment, tell your doctor right away. But if your symptoms seem life threatening or are related to stroke, call 911 or a local emergency number.

Risk of dementia

With dementia, you have problems with thinking, memory, and communication. This condition may cause symptoms such as:

Being age 65 years or older may increase this risk.

What might help

Your doctor may have you or a caregiver watch for symptoms of dementia during Imvexxy treatment. If you have any symptoms of dementia, talk with your doctor. They can give you certain tests to help check for this condition.

Risk of breast cancer

Breast cancer may cause symptoms such as:

Due to this risk, doctors typically won’t prescribe Imvexxy for people with current or past breast cancer.

What might help

Your doctor may recommend routine screenings and self-exams for breast cancer during Imvexxy treatment. If you have symptoms of breast cancer, tell your doctor right away. They’ll likely order tests to check for this condition.

Headache

Headache was a common side effect reported in studies of Imvexxy. Headache may cause symptoms such as a dull, sharp, or throbbing pain in your head.

What might help

If you have a bothersome or long lasting headache during Imvexxy treatment, talk with your doctor. They can recommend over-the-counter options to help ease your symptoms, such as Advil (ibuprofen) and Tylenol (acetaminophen). They may also suggest home remedies to help relieve your symptoms.

Allergic reaction

Like most drugs, Imvexxy can cause an allergic reaction in some people. But this side effect wasn’t reported in studies.

Symptoms can be mild to serious and include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • swelling under your skin (usually in your eyelids, lips, hands, or feet)
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms. Examples include:

  • an oral antihistamine, such as Benadryl (diphenhydramine)
  • a product you apply to your skin, such as hydrocortisone cream

If your doctor confirms you’ve had a mild allergic reaction to Imvexxy, they’ll decide whether you should continue using the drug.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Imvexxy, they may have you switch to a different treatment.

Keeping track of side effects

During your Imvexxy treatment, consider taking notes on any side effects you’re having. You can then share this information with your doctor. This is especially helpful when you first start taking a new drug or using a combination of treatments.

Your side effect notes can include things such as:

  • what dose of the drug you were using when you had the side effect
  • how soon you had the side effect after starting that dose
  • what your symptoms were
  • how your symptoms affected your daily activities
  • what other medications you were taking
  • any other information you feel is important

Keeping notes and sharing them with your doctor will help them learn more about how Imvexxy affects you. They can then use this information to adjust your treatment plan if needed.

Below is important information you should consider before using Imvexxy.

Boxed warnings

Imvexxy has boxed warnings about the following risks. Boxed warnings are the most serious warnings from the FDA.

Endometrial cancer: Imvexxy may increase the risk of endometrial cancer (a type of cancer that starts in the lining of your uterus). Due to this risk, doctors typically won’t prescribe Imvexxy for people with unusual genital bleeding that doesn’t have a known cause.

Heart and blood vessel problems: Imvexxy may increase the risk of heart and blood vessel problems. Examples include stroke and blood clots in a deep vein.

This risk may be higher in people with certain health factors, including:

Dementia: Imvexxy may increase the risk of dementia (problems with thinking, memory, and communication). Being age 65 years or older may increase this risk.

Breast cancer: Imvexxy may increase the risk of breast cancer. Due to this risk, doctors typically won’t prescribe Imvexxy for people with current or past breast cancer.

To learn more, see the “Side effects explained” section above.

Other warnings

Imvexxy can sometimes cause harmful effects in people who have certain conditions. This is known as a drug-condition interaction. Other factors may also affect whether Imvexxy is a good treatment option for you.

Talk with your doctor about your health history before you use Imvexxy. Be sure to tell them if any of the following factors apply to you:

* The active ingredient in Imvexxy is estradiol, which is a type of estrogen.

Alcohol and Imvexxy

There are no known interactions between alcohol and Imvexxy. If you have questions about consuming alcohol during Imvexxy treatment, talk with your doctor or pharmacist.

Pregnancy and breastfeeding with Imvexxy

Imvexxy is not usually prescribed for someone who’s pregnant or breastfeeding.

Pregnancy

It’s not known whether it’s safe to use Imvexxy during pregnancy.

Imvexxy is not prescribed for people who are pregnant or able to become pregnant. The drug is used to treat painful sex after menopause. People aren’t typically able to become pregnant after menopause.

If you’re having painful sex during pregnancy, talk with your doctor. They can help determine the cause and recommend ways to ease your symptoms.

Breastfeeding

Imvexxy may not be safe to use while breastfeeding. The drug contains estradiol (a type of estrogen), which may lower breast milk supply.

If you’re breastfeeding or planning to do so, talk with your doctor about your options.

Like most drugs, Imvexxy can cause a number of side effects that range from mild to serious. But most are temporary and go away after a few days to weeks. If you have questions about side effects that Imvexxy can cause, talk with your doctor.

Examples of questions to help get you started include:

  • Do any other medications I take raise my risk of side effects from Imvexxy?
  • Does my age increase my risk of any side effects from Imvexxy?
  • Do I have a higher risk of side effects from Imvexxy because of my health history?

To learn more about Imvexxy, see these articles:

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Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.