What is the recommended dosing for Tessalon (Benzonatate) pearls in a patient with a cough, considering factors such as age, weight, medical history, and potential interactions with other medications?

Tessalon (Benzonatate) Dosing

The standard adult dose of benzonatate (Tessalon Perles) is 100-200 mg orally three times daily, with a maximum daily dose of 600 mg. 1, 2

Standard Dosing Regimen

• Adults and children over 10 years: 100-200 mg orally three times daily (every 8 hours) as needed for cough 1, 2
• Maximum daily dose: 600 mg (three 200 mg doses) 1, 2
• Children under 10 years: Benzonatate is contraindicated due to risk of fatal overdose 3, 4

Critical Safety Warnings

Life-Threatening Risks

• Capsules must be swallowed whole and never chewed, crushed, or dissolved - doing so releases the medication rapidly and can cause severe local anesthesia of the oral mucosa, choking, and potentially fatal outcomes 3, 4
• Accidental ingestion in children can be rapidly fatal - even small amounts have caused death in infants and young children within 1 hour 3, 4
• Overdose in adults can cause cardiac arrest - ingestion of less than 30 capsules (6000 mg) has resulted in cardiac arrest, severe acidosis, and death 4

Common Adverse Effects

• Local numbness or tingling of the mouth and throat if capsule is chewed 5
• Sedation and dizziness 6
• Gastrointestinal upset 6

Clinical Position in Treatment Algorithm

Benzonatate is a fourth-line agent reserved for refractory cough that has failed multiple other therapies. 1, 2

Recommended Treatment Sequence:

1. First-line: Simple remedies (honey and lemon) or dextromethorphan 30-60 mg 1, 7
2. Second-line: Opioid derivatives (codeine, hydrocodone) if dextromethorphan fails 2
3. Third-line: Peripherally-acting antitussives (levodropropizine, moguisteine) 2
4. Fourth-line: Benzonatate 100-200 mg four times daily OR nebulized lidocaine 1, 2

When to Consider Benzonatate

• Opioid-resistant cough - particularly effective when codeine and other opioids have failed 5
• Patients requiring non-opioid alternatives - useful when opioid side effects are intolerable or opioids are contraindicated 6, 5
• Cancer-associated cough - shown 80% effectiveness in malignant pulmonary involvement unresponsive to opioids 2, 6

Special Populations

Renal Impairment

• No dose adjustment required - benzonatate is not renally excreted 1

Geriatric Patients

• Assess aspiration risk before prescribing - local anesthetic effects increase aspiration risk in frail elderly patients 2
• Use standard adult dosing but monitor closely for adverse effects 2

Pregnancy and Lactation

• Limited safety data available - use only if benefit clearly outweighs risk 6

Common Prescribing Pitfalls to Avoid

• Do not use as first-line therapy - benzonatate should only be tried after failure of simpler, safer agents like dextromethorphan 1, 2, 7
• Do not prescribe for children under 10 years - risk of fatal toxicity is too high 3, 4
• Warn patients explicitly about swallowing capsules whole - chewing or dissolving can be life-threatening 3, 4
• Do not continue indefinitely without reassessment - if no improvement after a short trial, discontinue and try alternative approaches 1
• Store securely away from children - accidental pediatric ingestion has caused rapid death 3, 4

Duration of Therapy

• Use for short-term symptomatic relief only 1
• If cough persists beyond 3 weeks despite treatment, discontinue benzonatate and pursue full diagnostic workup for underlying causes 1
• Reassess need for continued therapy regularly rather than prescribing chronic refills 1