Contraindications to Tessalon Perles (Benzonatate)
The only absolute contraindication to benzonatate is hypersensitivity to benzonatate or related compounds (such as tetracaine or procaine). 1
Absolute Contraindication
- Hypersensitivity: Benzonatate is absolutely contraindicated in patients with known hypersensitivity to benzonatate itself or structurally related local anesthetic compounds including tetracaine and procaine. 1
Critical Relative Contraindications and High-Risk Populations
High Aspiration Risk
- Patients with impaired airway protective reflexes should avoid benzonatate or use it only with extreme caution, as its local anesthetic effect causes oropharyngeal anesthesia that suppresses protective airway reflexes and significantly increases aspiration risk. 2
- This is particularly concerning in frail patients with serious illnesses, advanced cancer, or neurological conditions affecting swallowing. 2
Pregnancy and Breastfeeding
- Use benzonatate with caution in pregnant or breastfeeding women due to limited safety data; this represents a relative contraindication requiring individualized risk-benefit assessment. 2
- The American College of Chest Physicians specifically recommends caution in these populations given the lack of adequate safety studies. 3
Critical Safety Considerations
Pediatric Overdose Risk
- Benzonatate poses extreme danger to young children, with fatal outcomes reported after accidental ingestion of as few as 1-2 capsules in children under 10 years old. 4
- Five fatalities occurred in children 2 years and younger from accidental ingestions, with symptoms including seizures, cardiac arrest, and death occurring within 15 minutes of ingestion. 4
- The capsules must never be chewed or sucked, as release of the medication in the mouth causes local anesthesia that can lead to choking. 1
Overdose Potential
- Benzonatate overdose can rapidly cause life-threatening complications including seizures, cardiac arrest, dysrhythmias, coma, respiratory arrest, and death—sometimes within 15-30 minutes of ingestion. 5, 6, 4
- Intentional overdoses carry significant mortality risk, with 20 of 31 reported overdose cases resulting in death. 4
- There are no specific antidotes, and treatment is purely supportive. 7
Appropriate Use Parameters
Clinical Positioning
- Benzonatate should be reserved for opioid-resistant cough that has not responded to peripheral antitussives, not as first-line therapy. 8, 2
- The typical dosing is 100-200 mg up to four times daily. 8, 2
Administration Precautions
- The first dose should be administered in an inpatient setting to monitor for potential reflex bronchospasm. 8, 2
- Patients must avoid food and drink for at least one hour after administration. 8, 2
Common Pitfalls to Avoid
- Never prescribe benzonatate as first-line cough therapy—it should only be used after demulcents, opioids, and peripheral antitussives have failed. 8
- Ensure rigorous patient counseling about keeping medication away from children, never chewing or sucking capsules, and recognizing signs of overdose requiring immediate medical attention. 4
- Do not prescribe for extended periods without reassessing the underlying cause of cough, as chronic cough (>3 weeks) requires diagnostic evaluation rather than continued antitussive therapy. 9