Effects of Acetyl Cysteine on Sputum - Uses, Adverse Effects, and Precautions

Introduction

Sputum is a thick mucus produced in the lungs to keep the respiratory tract moist and trap foreign particles. Excess mucus production is seen during lung infection or disease. The coughing reflex attempts to cough up this mucus as sputum. Drugs like Acetylcysteine ease coughing by thinning the mucus secretions.

What Is N-Acetylcysteine?

N-Acetylcysteine is derived from the semi-essential amino acid cysteine. A semi-essential amino acid can be produced in the body. Cysteine can be produced if the body's serine (amino acid) and methionine (amino acid) are present. It plays a critical role in the synthesis of glutathione and glutamate. Glutathione is an important antioxidant that maintains cellular health and protects the liver and kidneys. Glutamate is a significant neurotransmitter in the brain. Individuals with psychiatric disorders like depression, obsessive-compulsive disorder (OCD), and Parkinson's disease are low in glutathione and glutamate. N-Acetylcysteine has mucolytic, antioxidant, cytoprotective, and anti-inflammatory properties.

What Is the Mechanism of Action of Acetylcysteine?

Acetylcysteine is metabolized in the liver and excreted in the urine. After administration of a single dose, it exerts its action for 5.6 hours. A sulfhydryl compound increases the synthesis of glutathione in the liver. Glutathione has antioxidant properties. It suppresses cytokine production and exhibits anti-inflammatory properties. It regulates oxidative metabolisms and influences cellular regulatory functions. It minimizes vasoconstriction and oxidative stress.

What Is A Mucolytic Agent?

N-Acetylcysteine is a mucolytic agent. It is primarily used for treating respiratory diseases. It thins and loosens the mucus, making it easier to cough out the sputum. It is given in conditions like emphysema, bronchitis, asthma, pneumonia, tuberculosis, and cystic fibrosis. It is available as an inhalation, intravenous solution, oral capsule, oral tablet, effervescent, and compound powder. It is inhaled using a nebulizer to dissolve the thick mucus.

What Are the Effects of Acetylcysteine on Sputum?

The thickness of the mucus depends on the concentration of the mucoproteins. The sulfhydryl compound exerts mucolytic action. It opens the disulfide linkages in the mucus and reduces its viscosity. This occurs between pH 7 and 9. This reduces the thickness of the mucus and makes it easier to cough up sputum. This relieves bronchospasm when Acetylcysteine is used as an inhalation agent with the nebulizer.

Why Should Acetylcysteine Be Given?

Mucus acts as the line of defense against various harmful pathogens. It protects the epithelium from irritants in the gastrointestinal tract. It consists of proteins like immunoglobulins, glycoproteins, and antimicrobial enzymes like lysozyme. The cross-bridging polymeric gel-forming mucins act as a protective barrier against bacteria and inhibit the growth of the bacteria. It also acts as a barrier against respiratory irritants.

The mucus-secreting cells and the mucociliary escalators regulate the production of mucus. Excess mucus production is seen in COPD (chronic obstructive pulmonary disease) and asthma because of chronic irritation of the airway. Excess mucus production reduces the clearance of mucus and results in the formation of mucus plugs. The viscosity of the mucus is increased, clearance is reduced, and this initiates inflammation and fibrosis. Acetylcysteine is given in these conditions to decrease the viscosity of mucus, increase its flowability, and improves the clearance rate to ease the coughing up of the sputum.

What Are the Indications of Acetylcysteine?

It is given for conditions like:

• Chronic emphysema.

• Emphysema with bronchitis.

• Chronic asthmatic bronchitis.

• Tuberculosis.

• Bronchiectasis.

• Primary amyloidosis of the lungs.

• Pneumonia.

• Bronchitis.

• Tracheobronchitis.

• Cystic fibrosis.

• For tracheostomy care.

• Atelectasis.

• Diagnostic studies like bronchograms, bronchospirometry, and bronchial wedge.

How Is It Administered?

Acetylcysteine is available as 10 % and 20 % solutions. It is given using a nebulizer - face mask, or mouthpiece. It is also directly instilled into the tracheostomy tube. It is also given through a percutaneous intrathecal catheter. Acetylcysteine is administered as a fine nebula from the nebulizer. The nebulized solution is directly inhaled from the nebulizer or through an attached face mask or mouthpiece.

What Are the Other Uses of Acetylcysteine?

• It is used as an antidote for Paracetamol overdose.

• It preserves lung function and prevents exacerbation in COPD (chronic obstructive pulmonary disease).

• It prevents contrast-induced nephropathy in patients undergoing radiologic procedures.

• It reduces the effect of influenza infection.

• It prevents deterioration of lung function in idiopathic pulmonary fibrosis.

• It is used along with clomiphene in treating polycystic ovary syndrome and infertility.

• It may prevent post-surgical pulmonary complications in patients undergoing esophagectomy for cancer.

• It is used as an adjunct in the treatment of Helicobacter pylori infection.

• It is used in treating psychiatric disorders as it regulates the levels of glutamate, an important neurotransmitter in the brain.

• It stimulates the production of glutathione, an antioxidant that maintains cellular health.

What Are the Adverse Effects of Acetylcysteine?

Adverse effects are uncommon, but nausea, vomiting, diarrhea, transient skin rash, flushing, epigastric pain, and constipation may occur. When higher doses are given to treat Acetaminophen overdose, it may cause headache, tinnitus, urticaria, fever, chills, and anaphylaxis.

What Are the Precautions to Be Taken?

• Acetylcysteine is contraindicated in patients with previous allergies.

• It is used with caution in patients with a history of bronchospasm.

• Nebulized Acetylcysteine should be used with caution in patients with inadequate cough reflexes.

• Oral Acetylcysteine can induce vomiting and increase the risk of upper gastrointestinal bleeding in patients with esophageal varices or peptic ulcers.

• Intravenous Acetylcysteine should be used with caution in patients with heart failure and renal diseases because intravenous administration increases the volume load and results in hyponatremia (low level of sodium in the blood), seizures, and death in severe cases.

• It is also used with caution in pediatric patients requiring fluid restriction.

• It has inadequate studies for determining the risks in pregnant and breastfeeding women.

Conclusion:

Acetylcysteine is a well-known drug used to treat respiratory disorders to break mucus plugs. It is a safe and non-toxic drug. It has remarkable antioxidant and anti-inflammatory properties. It is also used in managing the symptoms of COVID (coronavirus disease). Acetylcysteine is also a dietary supplement for liver protection and immune system function. It is important to consult the physician before consuming Acetylcysteine, and it is not safe to self-medicate.