From the FDA Drug Label
When nebulized into a face mask, mouth piece, or tracheostomy, 1 to 10 mL of the solution may be given every 2 to 6 hours; the recommended dose for most patients is 3 to 5 mL of the solution 3 to 4 times a day The recommended dosing of N-acetylcysteine for excessive mucous production in the US is:
- 3 to 5 mL of the solution 3 to 4 times a day when nebulized into a face mask, mouth piece, or tracheostomy 1
- 1 to 2 mL of solution may be given as often as every hour when used by direct instillation
- 1 to 2 mL of the solution every 1 to 4 hours by instillation into the tracheostomy for routine nursing care of patients with tracheostomy.
From the Research
N-acetylcysteine (NAC) for excessive mucus production is typically dosed at 600 mg twice daily by mouth in the United States, as supported by the most recent and highest quality study 2. For more severe cases, dosing may be increased to 600 mg three times daily. NAC is available as an over-the-counter supplement in capsule, powder, or effervescent tablet forms. When starting NAC, begin with the standard dose and allow 1-2 weeks to evaluate effectiveness before adjusting. Some key points to consider when using NAC include:
- Take it with food to minimize potential gastrointestinal side effects like nausea or heartburn.
- Adequate hydration is essential while using NAC to help thin mucus.
- NAC works by breaking disulfide bonds in mucus proteins, making thick secretions less viscous and easier to clear.
- It also has antioxidant properties and helps replenish glutathione levels in the body.
- Common side effects include nausea, vomiting, and an unpleasant sulfur smell.
- If using NAC long-term, periodic liver function monitoring is advisable.
- Consult a healthcare provider before starting NAC, especially if taking other medications, as it may interact with certain drugs including some antibiotics and nitroglycerin, as noted in a review of its clinical usefulness 3. The use of NAC as a mucolytic agent has been studied in various contexts, including its effects on airway epithelial function in dogs 4, and its potential benefits in treating chronic obstructive pulmonary disease (COPD) 2. Overall, NAC appears to be a safe and effective treatment for excessive mucus production, with a range of potential benefits and minimal side effects, as supported by the available evidence 5, 2, 3.