Once you’ve finished initial treatments for breast cancer, your doctor’s number one goal will be keeping your cancer from growing or coming back. Depending on the type of breast cancer you have, your doctor may prescribe long-term hormonal therapy to help accomplish this goal and extend the length of time that your cancer is in remission (periods when all signs of cancer disappear).

Letrozole (Femara) is hormone-therapy medication for treating estrogen receptor-positive (ER-positive) breast cancers in people who’ve gone through menopause. Like any drug, letrozole can cause side effects, including a sore throat. In this article, we’ll explore some other potential causes of a sore throat and provide some tips you can try at home to help manage this side effect.

What Is Letrozole?

Some cancers may grow if your body has too much of the hormone estrogen. Known as estrogen-dependent or estrogen receptor-positive cancers, they can include breast, ovarian, and endometrial cancers.

Letrozole is a type of medication known as an nonsteroidal aromatase inhibitor (NSAI). Aromatase inhibitors work to treat ER-positive cancers by decreasing how much estrogen your body makes. In doing so, letrozole helps slow down or stop the growth of ER-positive cancer. Other examples of aromatase inhibitors include anastrozole (Arimidex) and exemestane (Aromasin).

Doctors often prescribe letrozole or another form of hormonal therapy for people who have completed initial breast cancer treatments to reduce the risk of recurrence (cancer coming back).

Letrozole May Cause a Sore Throat

In addition to more common side effects like back pain, chest pain, and hot flashes, letrozole can also cause a sore throat. A few MyBCTeam members have reported a sore throat while taking aromatase inhibitors.

Sore throat seems to be one of the less-common side effects of letrozole. However, the medication can also cause a cough, sores in your mouth or throat, dry mouth, and nausea — all of which may make your throat hurt.

In addition, letrozole can reduce your white blood cell levels, which can increase your risk of developing infections. Some infections, caused by viruses, bacteria, or fungi, can cause a sore throat. To support your immune health, practice good hygiene, like washing your hands regularly, to reduce your risk of infections.

Always talk with your doctor about new or bothersome side effects. They can help determine whether what you’re experiencing is normal and provide ways to cope with side effects.

Other Potential Causes of a Sore Throat

Although taking letrozole may cause a sore throat, there are several other reasons you may develop this symptom.

Dehydration

Not drinking enough fluids can lead to dehydration, which can make your throat feel dry and sore. Letrozole can also cause dry mouth, so it’s crucial to stay hydrated by drinking plenty of water and other hydrating beverages throughout the day. This can help keep your throat moist and prevent you from developing a dry, sore throat.

Other Medications

Certain medications, including those used in cancer treatment, may have side effects that cause throat irritation and soreness. For instance, both chemotherapy drugs and radiation therapy can cause mucositis, a condition that causes inflammation and sores in your mouth and throat.

If you take letrozole alongside other medications, discuss with your health care team the potential side effects and interactions that may contribute to a sore throat.

Oral Thrush

Oral thrush (candidiasis) is caused by a fungal infection in your mouth or throat. In addition to a sore throat, oral thrush can cause you to develop white patches in your mouth and throat, a cottony feeling in your mouth, and pain while eating or swallowing.

While oral thrush is not common in healthy adults, medications used to treat breast cancer may increase your risk of getting this infection.

Acid Reflux

Acid reflux (heartburn), a condition where stomach acid flows back into the throat, can cause throat irritation and soreness. You may experience acid reflux as a side effect of certain medications, because of stress, or due to changes in your eating habits during treatment.

Treating a Sore Throat

When experiencing a sore throat as a possible side effect of letrozole, there are strategies you can use to minimize discomfort.

Stay Hydrated

Drink plenty of fluids throughout the day to keep your throat moist and prevent dehydration, which can make a sore throat worse. When choosing things to drink, opt for soothing beverages like warm herbal teas, lukewarm water, or clear broths.

The U.S. National Academies of Sciences, Engineering, and Medicine recommends a daily intake of about 11.5 cups (2.7 liters) of fluids a day for women and 15.5 cups (3.7 liters) for men.

Practice Good Oral Hygiene

Maintaining good oral hygiene is important when managing a sore throat, especially if it’s caused by oral thrush. Be sure to brush your teeth twice daily with a soft-bristled toothbrush and use a mild, nonirritating toothpaste. Rinse with water or an alcohol-free mouthwash after meals to keep your mouth clean and reduce the risk of infection.

A MyBCTeam member recommended Biotene mouthwash and toothpaste, saying, “It made my mouth feel nice and hydrated, but not overpowered.”

Try Mouth Rinses and Washes

Several MyBCTeam members recommend rinsing your mouth and throat. While there are several types of mouthwash available over the counter for sore throat, many members recommend getting a prescription for “magic mouthwash,” the nickname for a prescription-strength mouthwash that contains a mixture of medications to help decrease the pain caused by a sore throat. One member said that they “swear by it.”

It’s important to note that there are many different recipes for magic mouthwash. Your doctor will prescribe the version that should work best for you.

You can also gargle warm salt water to help with a sore throat. Gargling with warm salt water can help reduce inflammation and provide temporary relief for a sore throat. To try it:

1. Mix 1/2 teaspoon of salt with 8 ounces of warm water.
2. Stir until the salt dissolves.
3. Gargle the solution for 30 seconds before spitting it out.

One MyBCTeam member makes a similar mouth rinse recommended by their dentist. The recipe for the rinse is 1 cup of water, 1/4 teaspoon of baking soda, and 1/8 teaspoon of salt.

Use Over-the-Counter Medications for Sore Throats

There are several over-the-counter medications and remedies that can help a sore throat.

• Throat lozenges and sprays can provide temporary relief by numbing the throat and reducing pain and irritation. Look for lozenges that contain ingredients like menthol or benzocaine, which can provide a soothing effect.
• Over-the-counter pain medications such as ibuprofen can help dull the pain of a sore throat.
• Antihistamines can help thin mucus in your nose and throat that may be contributing to your sore throat.

Be sure to talk with your doctor before adding any medication — even over-the-counter ones — to your treatment plan.

Humidify the Air

Dry air can make a sore throat feel worse. Use a humidifier in your home, particularly in your bedroom while sleeping, to add moisture to the air and relieve throat dryness.

If you use a humidifier, make sure to follow the manufacturer’s instructions on how to keep it clean. A dirty water tank or filter can become a breeding ground for bacteria or mold which can release into the air with steam or mist, potentially causing flu-like symptoms or even lung illness.

If you don’t have a humidifier, taking a steamy shower can also help increase humidity temporarily.

Avoid Irritants and Triggers

Identify and avoid any irritants or triggers that may make your sore throat worse. This may include:

• Acidic foods
• Dust
• Allergens
• Strong chemical odors
• Cigarette smoke

Talk With Your Health Care Professionals

While all of these strategies may help, you may find it useful to talk with your doctor and other health care professionals about other potential treatment options if your sore throat does not go away. Sometimes changing your dose or switching to another aromatase inhibitor can help decrease side effects.

Talk With Others Who Understand

MyBCTeam is the social network for people with breast cancer and their loved ones. On MyBCTeam, more than 64,000 members come together to ask questions, give advice, and share their stories with others who understand life with breast cancer.

Have you experienced a sore throat while taking letrozole? How did you manage it? Share your experience in the comments below, or start a conversation by posting on your Activities page.