ADRYL 2% SYRUP

Indications

• Chronic obstructive pulmonary disease (COPD)
• Asthma
• Cystic fibrosis
• Chronic bronchitis

Dosage

Children: Refer to the BNF for Children for specific pediatric dosing recommendations.

Adults: Refer to the BNF for specific dosing information. Generally, the usual adult dose is 750 mg three times daily.

Mechanism of action

Carbocysteine restores the balance between sialomucins and fucomucins in mucus, likely through the stimulation of the sialyl transferase enzyme. This action decreases mucus viscosity, enhances mucociliary clearance, and reduces bacterial adherence to respiratory epithelial cells. Furthermore, it has shown to inhibit inflammation by suppressing NF-κB and ERK1/2 MAPK signaling pathways and reducing the expression of intracellular adhesion molecule 1 (ICAM-1), thus preventing viral infections and airway inflammation.

Pharmacodynamics

Carbocysteine significantly reduces sputum viscosity, cough, dyspnea, and fatigue associated with respiratory conditions. Its mucolytic action aids in clearing mucus from the respiratory tract, which is vital for preventing pulmonary infections, particularly during exacerbations of COPD. Additionally, carbocysteine exhibits anti-inflammatory properties and may protect lung cells from oxidative stress.

Pharmacokinetics

Carbocysteine is absorbed well from the gastrointestinal tract and has a bioavailability of approximately 75%. It undergoes extensive metabolism in the liver and is excreted primarily in the urine. The onset of action is typically within a few days of starting treatment, with a duration of effect lasting up to several hours. Half-life and specific metabolic pathways were not provided.

Adverse effects

• Gastrointestinal disturbances
• Nausea
• Diarrhea
• Rash
• Pruritus
• Dizziness

Precautions

• Use with caution in patients with a history of peptic ulcer
• Patients with asthma should be monitored as carbocisteine can cause bronchospasm in some individuals

Pregnancy

Carbocisteine should only be used in pregnancy if the potential benefit justifies the potential risk to the fetus, as there is limited data on its safety.

Breast-feeding

There is insufficient information on the excretion of carbocisteine in human milk, hence caution is advised when administering to breastfeeding mothers.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Oral solution
• Capsules
• Syrup

Mechanism of action

The hypersecretion of mucus characterizes serious respiratory conditions including asthma, cystic fibrosis (CF), and chronic obstructive pulmonary disease (COPD). It blocks bacterial adherence to cells, preventing pulmonary infections. Glycoproteins (fucomucins, sialomucins and sulfomucins) regulate the viscoelastic properties of bronchial mucus. Increased fucomucins can be found in the mucus of patients with COPD. Carbocisteine serves to restore equilibrium between sialomucins and fucomucins, likely by intracellular stimulation of sialyl transferase enzyme, thus reducing mucus viscosity. A study found that L-carbocisteine can inhibit damage to cells by hydrogen peroxide (H2O2) by activating protein kinase B (Akt) phosphorylation, suggesting that carbocisteine may have antioxidant effects and prevent apoptosis of lung cells. There is some evidence that carbocisteine suppresses NF-κB and ERK1/2 MAPK signalling pathways, reducing TNF-alpha induced inflammation in the lungs, as well as other inflammatory pathways. An in-vitro study found that L-carbocisteine reduces intracellular adhesion molecule 1 (ICAM-1), inhibiting rhinovirus 14 infection, thereby reducing airway inflammation.

Pharmacodynamics

Due to its mucolytic effects, carbocisteine significantly reduces sputum viscosity, cough, dyspnea and fatigue. Additionally, it prevents pulmonary infections by decreasing accumulated mucus in the respiratory tract; this is especially beneficial in preventing exacerbations of COPD caused by bacteria and viruses. It has in-vitro anti-inflammatory activity with some demonstrated action against free radicals.