How Does Acetylcysteine Work?

Acetylcysteine, also known as N-acetylcysteine, is a mucolytic agent which breaks up the mucus in the respiratory tract and reduces its viscosity, making it easier to cough up and clear from the lungs. Acetylcysteine also has anti-inflammatory and antioxidant properties.

Acetylcysteine lowers mucus viscosity by splitting the disulfide bonds of mucoproteins, which are vital for their structure and stability. Acetylcysteine is also an antioxidant that protects the lungs by scavenging the free radicals generated by inflammatory cells.

Acetylcysteine is an orally inhaled solution that is turned into a fine mist using a nebulizer. Acetylcysteine is used in the treatment of the following conditions:

FDA-approved:

• To thin the mucus and relieve chest congestion in pulmonary diseases such as:
  • Asthma
  • Emphysema
  • Bronchitis
  • Cystic fibrosis
• Diagnostic bronchography
• Acetaminophen overdose (oral or intravenous)

Off-label:

• Prevention of contrast agent-associated nephrotoxicity administered orally
• Keratoconjunctivitis sicca (dry eyes), administered as eye drops

Orphan designation:

• Prevention of ototoxicity (toxicity to ears that can affect hearing and balance) caused by platinum-based chemotherapy to treat pediatric cancers

Side effects of acetylcysteine may include the following:

• Bronchoconstriction
• Bronchospasm
• Chest tightness
• Hemoptysis (coughing up blood)
• Increased volume of bronchial secretions
• Irritation of tracheal or bronchial tract
• Rhinorrhea (nasal discharge)
• Stomatitis (inflammation of oral mucosa)
• Disagreeable odor
• Drowsiness
• Fever
• Nausea
• Vomiting

Information contained herein is not intended to cover all possible side effects, precautions, warnings, drug interactions, allergic reactions, or adverse effects. Check with your doctor or pharmacist to make sure these drugs do not cause any harm when you take them along with other medicines. Never stop taking your medication and never change your dose or frequency without consulting your doctor.

Generic and brand names of acetylcysteine drugs include:

• acetylcysteine
• N-acetylcysteine