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Fess (Functional Endoscopic Sinus Surgery)

Medically reviewed by Last updated on May 1, 2023.


What you need to know about functional endoscopic sinus surgery (FESS):

FESS removes tissue that blocks your sinus openings. This helps improve airflow and restores normal sinus function.

How to prepare for FESS:

  • Your surgeon will tell you how to prepare for surgery. He or she may tell you not to eat or drink anything after midnight on the day of your surgery. Arrange to have someone drive you home and stay with you for 24 hours.
  • Tell your surgeon about all medicines you currently take. He or she will tell you if you need to stop any medicine for surgery, and when to stop. He or she will tell you which medicines to take or not take on the day of surgery.
  • Tell your surgeon about any allergies you have, including to medicines or anesthesia.

What will happen during FESS:

  • You will be given general anesthesia to keep you asleep and free from pain during surgery. Your surgeon will use an endoscope and other small tools. Tissue that is blocking your sinus openings will be removed. A small rotating burr may also be used to widen your sinuses or scrape away tissue.
  • Samples of the tissues that are removed may be sent to the lab for tests. Bleeding will be controlled using a cauterizing device. Nasal packing, such as gauze or cotton, will be placed in your nostrils to help control bleeding and prevent infection.

What to expect after FESS:

  • You may have some pain, swelling, bruising, or bleeding after surgery. Your nose may feel stuffy. You may notice crusting. These are all normal and should get better within a few days to weeks.
  • Medicines may be given to prevent or treat pain, swelling, or a bacterial infection. Steroid medicine for swelling may be given as a spray. Your surgeon will tell you when to start using the spray, and how often to use it.
  • You may be shown how to do nasal washes with saline. You may need to do this 2 times each day.
  • You will need to go to regular follow-up visits for up to 3 months. Your surgeon will check to make sure the surgery area is healing well.
  • Your nasal cavity may need to be cleaned and have scar tissue removed. This may happen more than 1 time. A spacer or stent may be placed to keep the area open.
  • Your surgeon will tell you when it is okay to drive and do your daily activities after surgery.

Risks of FESS:

You may bleed more than expected or get an infection. Your eyes, blood vessels, nerves, or other areas may get injured during surgery. You may have trouble breathing or develop rhinosinusitis again.

Call your local emergency number (911 in the US) if:

  • You have clear fluid coming from your nose.
  • You have trouble breathing, seeing, talking, or thinking clearly.

Seek care immediately if:

  • You have a stiff neck or eye pain, especially when you look directly at light.
  • You have a severe headache that does not go away even after you take pain medicine.
  • Your face is getting numb.
  • You have pus or a foul-smelling odor coming from your nose.
  • Blood soaks through your nasal packing.

Call your doctor or surgeon if:

  • You have a fever or chills.
  • You have bruises or swelling around your nose or eyes.
  • You have nausea or are vomiting.
  • Your skin is itchy, swollen, or has a rash.
  • You have questions or concerns about your condition or care.


You may need any of the following:

  • Prescription pain medicine may be given. Ask your healthcare provider how to take this medicine safely. Some prescription pain medicines contain acetaminophen. Do not take other medicines that contain acetaminophen without talking to your healthcare provider. Too much acetaminophen may cause liver damage. Prescription pain medicine may cause constipation. Ask your healthcare provider how to prevent or treat constipation.
  • NSAIDs , such as ibuprofen, help decrease swelling, pain, and fever. NSAIDs can cause stomach bleeding or kidney problems in certain people. If you take blood thinner medicine, always ask your healthcare provider if NSAIDs are safe for you. Always read the medicine label and follow directions.
  • Antibiotics help prevent an infection.
  • Take your medicine as directed. Contact your healthcare provider if you think your medicine is not helping or if you have side effects. Tell your provider if you are allergic to any medicine. Keep a list of the medicines, vitamins, and herbs you take. Include the amounts, and when and why you take them. Bring the list or the pill bottles to follow-up visits. Carry your medicine list with you in case of an emergency.

Nasal packing:

Ask your surgeon how long the nasal packing will stay inside your nose. If it needs to be removed and replaced at home, ask how to do this.


  • Your surgeon will tell you when you can return to your normal daily activities. Do not travel by airplane or go SCUBA diving for 4 weeks. Do not exercise, do strenuous activity, or go swimming for 2 weeks, or as directed. Your surgeon may also tell you not to bend over, lift anything heavier than 10 pounds, or strain.
  • Do not blow your nose for 1 week, or as directed. You might damage the surgery area by blowing your nose.
  • Use a cool-mist humidifier to increase air moisture in your home. This may make it easier for you to breathe and help thin your nasal discharge. Wash the humidifier each day with soap and warm water to keep it free of germs.
  • Rinse or moisten your nose with salt water as directed. This may help loosen any dried blood or mucus. Ask for more information on how to prepare and do nasal washings.
  • Wash your hands often. Use soap and water. Wash your hands after you use the bathroom, change a child's diapers, or sneeze. Wash your hands before you prepare or eat food.
  • Drink liquids as directed. Ask how much liquid to drink each day and which liquids are best for you. Limit the amount of caffeine you drink.

Follow up with your doctor or surgeon as directed:

Write down your questions so you remember to ask them during your visits.

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The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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