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URL of this page: https://medlineplus.gov/druginfo/meds/a615021.html

Acetylcysteine Oral Inhalation

pronounced as (a seet'' il sis' teen)

Why is this medication prescribed?

Acetylcysteine inhalation is used along with other treatments to relieve chest congestion due to thick or abnormal mucous secretions in people with lung conditions including asthma, emphysema, bronchitis and cystic fibrosis (an inborn disease that causes problems with breathing, digestion, and reproduction). Acetylcysteine is in a class of medications called mucolytic agents. It works by thinning the mucus in the air passages to make it easier to cough up the mucus and clear the airways.

How should this medicine be used?

Acetylcysteine comes as a solution (liquid) and concentrated solution to inhale by mouth using a nebulizer (machine that turns medication into a mist that can be inhaled). When using a nebulizer, it is usually used 3 to 4 times a day. When given by other methods, acetylcysteine should be used as directed. Use acetylcysteine at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use acetylcysteine exactly as directed. Do not use more or less of it or use it more often than prescribed by your doctor. Only mix acetylcysteine with other medications if instructed to do so by your doctor.

The concentrated solution of acetylcysteine should be mixed with normal saline or sterile water and used within an hour.

There may be a slight unpleasant odor when you use acetylcysteine that goes away quickly. In an opened bottle of acetylcysteine, there may be a color change to a light purple, but it will not affect use.

Acetylcysteine should only be used with nebulizers made of plastic or glass. Acetylcysteine should not be routinely used in a hand bulb operated nebulizer or put directly into a heated nebulizer. Talk to your doctor or pharmacist about the correct nebulizer to use with acetylcysteine.

Clean your nebulizer immediately following each use. If you do not clean your nebulizer properly, the nebulizer may become clogged and may not allow medication to be inhaled. Follow the manufacturer's directions carefully and ask your doctor or pharmacist if you have any questions about cleaning your nebulizer.

Other uses for this medicine

Acetylcysteine is also sometimes used to treat people who have taken or received an overdose of acetaminophen (Tylenol, others). Talk to your doctor about the risks of using this medication for your condition.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before using acetylcysteine,

  • tell your doctor and pharmacist if you are allergic to acetylcysteine, any other medications, or any of the ingredients in acetylcysteine inhalation. Ask your pharmacist for a list of the ingredients.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take.
  • tell your doctor if you have or have ever had asthma.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while using acetylcysteine, call your doctor.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Use the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not use a double dose to make up for a missed one.

What side effects can this medication cause?

Acetylcysteine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • nausea
  • vomiting
  • fever
  • runny nose
  • swelling of the inside of the mouth
  • throat irritation
  • drowsiness
  • cool, moist skin

Some side effects can be serious. If you experience any of these symptoms call your doctor immediately or get emergency medical treatment:

  • chest tightness
  • wheezing
  • difficulty breathing or swallowing
  • coughing up blood
  • hives
  • rash
  • itching

Acetylcysteine may cause other side effects. Call your doctor if you have any unusual problems while using this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). After opening, keep this medication in the refrigerator, and dispose of any unused medication after 96 hours.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (https://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.org

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor.

Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Mucomyst®

Other names

  • N-Acetylcysteine

This branded product is no longer on the market. Generic alternatives may be available.

Last Revised - 03/15/2017