Ambroxol

BRAND NAMES

Mucolite: A widely recognized brand in India by Dr. Reddy's.

Ambrodil: Another popular Indian brand, sometimes combined with Salbutamol.

Inhalex: A Cipla product available in India.

Lasolvan / Mucosolvan: Very common international brand names.

Mucoangin: Another name for Ambroxol, especially in some European markets.

Bisolvon: A well-known brand in countries like Switzerland.

MECHANISM OF ACTION

Ambroxol acts primarily as a mucolytic and expectorant agent. It works by reducing the viscosity of mucus in the respiratory tract through the breakdown of mucopolysaccharide fibers, making the mucus thinner and less sticky. Ambroxol also stimulates the secretion of surfactant from type II alveolar cells, which helps prevent mucus from adhering to the airway walls and improves its clearance. In addition, it enhances ciliary activity in the bronchial epithelium, promoting effective mucociliary transport of mucus toward the throat for expulsion. Ambroxol also exhibits mild anti-inflammatory and local anesthetic effects, which can help reduce airway irritation and coughing.

PHARMACOKINETICS

Absorption

Ambroxol is quickly and almost completely absorbed following oral administration. However, it undergoes extensive first-pass metabolism in the liver, leading to an absolute bioavailability of about 79% for immediate-release (IR) formulations.

Distribution

After oral administration, ambroxol has a large volume of distribution of approximately 552 liters, which corresponds to about 7 L/kg.

Metabolism

Ambroxol is primarily metabolized in the liver. It undergoes phase I and phase II metabolic reactions, mainly through oxidation and conjugation processes. The principal metabolic pathway involves conversion to dibromoanthranilic acid, along with the formation of various glucuronide conjugates. These metabolites are pharmacologically inactive and are eliminated mainly through the renal route. Hepatic metabolism plays a key role in ambroxol clearance, which is why liver function can influence its pharmacokinetics.

Excretion

Approximately 90% of ambroxol is excreted through the urine, mainly in the form of metabolites, while less than 10% is eliminated as unchanged drug. A small fraction, around 5–10%, is excreted via the feces.

PHARMACODYNAMICS

Ambroxol is a mucoactive drug with multiple pharmacodynamic actions. Its main effects are mucolytic and secretagogue activities that enhance mucus clearance from the respiratory tract. In addition, it exhibits anti-inflammatory, antioxidant, local anesthetic, and possible neuroprotective properties.

DOSAGE AND ADMINISTRATION

1. Adults:

• Immediate-release tablets: 30 mg 3 times daily

• Extended-release tablets: 75 mg twice daily

• Syrup: 10 mL (typically 30 mg) 3 times daily

2. Children:

• 0–2 years: 3–5 mg 3 times daily (usually as syrup)

• 2–5 years: 5–7.5 mg 3 times daily

• 6–12 years: 15 mg 3 times daily

3. Neonates and infants:

• Only under medical supervision, often 1–2 mg/kg/day divided into 2–3 doses.

4. Inhalation (nebulizer):

• Usually 3–5 mL of solution 3 times daily for patients with severe mucus obstruction.

Administration Tips:

• Can be taken with or without food.

• Adequate hydration helps maximize the mucolytic effect.

Duration: Usually 5–10 days, depending on symptoms.

DRUG INTERACTIONS

Ambroxol generally has a good safety profile, but certain drug interactions should be considered. It may be less effective if taken with cough suppressants such as codeine or dextromethorphan, because these reduce the cough reflex needed to clear mucus. Ambroxol can also enhance the penetration of some antibiotics, like amoxicillin or erythromycin, into the bronchial secretions, potentially increasing their effectiveness. Combining ambroxol with other mucolytic agents is usually not recommended without medical guidance, as it may increase the risk of gastrointestinal irritation. Aside from these, ambroxol has minimal interactions with most common medications, including antihypertensives and antipyretics, making it generally safe for use.

FOOD INTERACTIONS

Ambroxol does not have any major food restrictions, but it is generally advised to take it with food to reduce the risk of stomach upset. Any specific food interactions are usually related to other active ingredients when ambroxol is used in combination medications.

CONTRAINDICATIONS

Ambroxol is contraindicated in patients with a known allergy to ambroxol or bromhexine, in those with active peptic ulcers, and in individuals with severe liver or kidney impairment. Certain formulations are also not recommended for neonates under 2 years without medical supervision.

SIDE EFFECTS

Common Side Effects:

• Nausea and vomiting.

• Diarrhea.

• Stomach or abdominal pain/discomfort

• Indigestion or heartburn.

• Dry mouth or throat.

• Taste disturbances (dysgeusia), sometimes a metallic taste.

• Numbness in the mouth, tongue, or throat (oral and pharyngeal hypoaesthesia).

• Mild skin rash or itching.

• Headache.

• Dizziness or weakness.

OVERDOSE

Symptoms of an ambroxol overdose may include:

• Nausea and vomiting.

• Diarrhea.

• Abdominal pain or stomach upset (dyspepsia).

• Heartburn (pyrosis).

• Restlessness (in extreme cases).

• Increased salivary secretion and retching.

• Skin rashes and other hypersensitivity reactions.

TOXICITY

Ambroxol is generally considered safe at therapeutic doses, and serious toxicity is rare. However, overdose can lead to symptoms such as nausea, vomiting, diarrhea, and abdominal pain. In some cases, dizziness, headache, or allergic reactions may occur. Severe toxicity is uncommon, and there is no specific antidote; treatment is usually supportive and symptomatic, including hydration and monitoring.