Tessalon Perles (Benzonatate) Dosing for Adults
The standard adult dose of benzonatate is 100-200 mg orally three times daily as needed for cough, with a maximum daily dose of 600 mg. 1
Standard Dosing Regimen
- Dose: 100-200 mg per dose 1
- Frequency: Three times daily (every 8 hours) 1
- Maximum daily dose: 600 mg 1
- Administration: Swallow capsules whole; do not chew, dissolve, or break them 1
Critical Safety Considerations
Life-Threatening Risks with Overdose
Benzonatate overdose can cause rapid cardiac arrest and death, even in adults, making rational prescribing and patient education essential. 2, 3
- Ingestion of as few as 10 capsules (2000 mg) has resulted in cardiac arrest in a 17-year-old patient 2
- Adult cardiac arrest has occurred with ingestion of less than 30 capsules (6000 mg) 3
- Life-threatening events can develop within 1-2 hours of ingestion 2, 3
- Adverse effects include seizures, cardiac dysrhythmias (including bradyarrhythmias), metabolic acidosis, and potential for permanent neurological damage including blindness 2, 3
Administration Warnings
- Never chew or dissolve capsules: Local anesthesia of the oral mucosa can occur, leading to choking risk 1
- The medication provides rapid oropharyngeal anesthesia within approximately 55 seconds when capsules are opened or chewed 1
- Fatal cases have been reported in children who chewed the capsules 4
Clinical Pearls
- Benzonatate is structurally similar to local anesthetics (tetracaine, procaine), which explains its toxicity profile 2, 3
- Limited treatment options exist for overdose; management is primarily supportive with ACLS protocols 2, 3
- The medication's seemingly innocuous nature as a nonnarcotic antitussive belies its significant toxicity potential 2, 3