What is the recommended dosage and usage of Benzonatate for cough relief?

Benzonatate Dosage and Usage for Cough Relief

The recommended dosage of benzonatate for cough relief is 100-200 mg three times daily as needed, with a maximum daily dose of 600 mg. 1

Dosage Guidelines

• Standard adult dosage: 100-200 mg three times daily
• Maximum daily dose: 600 mg (in three divided doses)
• Age restriction: Only for adults and children over 10 years of age
• Administration: Capsules must be swallowed whole, never broken, chewed, dissolved, cut, or crushed

Placement in Cough Treatment Algorithm

Benzonatate is typically used when other treatments have failed, particularly in the following sequence:

1. First-line: Demulcents (simple linctus, honey-lemon mixtures)
2. Second-line: Opiate derivatives (codeine, hydrocodone)
3. Third-line: Peripherally acting antitussives (levodropropizine, moguisteine)
4. Fourth-line: Local anesthetics including benzonatate 2

Mechanism and Efficacy

Benzonatate works as a peripheral antitussive by anesthetizing stretch receptors in the lungs, thereby reducing the cough reflex. It is chemically related to para-amino-benzoic acid class anesthetics (like procaine and tetracaine) 1. Studies have shown it to be effective in:

• Opioid-resistant cough in advanced cancer 3
• Acute viral cough when combined with guaifenesin 4

Important Safety Warnings

• Serious risk of overdose: Can cause cardiac arrest and death within 15-20 minutes of accidental ingestion 5
• Local anesthesia risk: If capsules are chewed or broken, can cause numbness of mouth/throat and potential choking
• CNS effects: May cause adverse central nervous system effects
• Pregnancy: Category C - use only if clearly needed
• Pediatric use: Not established for children under 10 years; accidental ingestion has resulted in death 1

Special Considerations

• Elderly patients: Menthol-based products may be safer for elderly patients with cardiovascular or renal comorbidities 6
• Cancer patients: Benzonatate has shown efficacy in cancer-related cough that is unresponsive to opioids 2, 3
• Duration: If a short course of treatment does not lead to improvements, the treatment should be discontinued and another approach tried 2

Patient Instructions

• Swallow capsules whole with water
• If numbness or tingling of mouth/tongue occurs, avoid eating or drinking until resolved
• Seek medical attention if symptoms persist or worsen
• Do not exceed recommended dosage
• Keep out of reach of children

Benzonatate offers an alternative for patients with persistent cough who have not responded to other treatments, but should be used with caution due to its safety profile and potential for serious adverse effects if misused.