TESSALON
Clinical safety rating: caution
Comprehensive clinical and safety monograph for TESSALON (TESSALON).
Benzonatate is a local anesthetic structurally related to tetracaine that inhibits pulmonary stretch receptors and reduces the cough reflex by decreasing the sensitivity of vagal afferent fibers in the respiratory tract.
| Metabolism | Preferentially metabolized by cholinesterase and other plasma esterases to inactive metabolites. |
| Excretion | Renal: <5% unchanged; primary route is hepatic metabolism with metabolites excreted renally and fecally; exact biliary/fecal % not established in humans. |
| Half-life | Terminal elimination half-life is approximately 12-15 hours in adults; significant interindividual variability. No accumulation with q6h dosing. |
| Protein binding | Approximately 60-70%, primarily to albumin. |
| Volume of Distribution | ~2.5 L/kg; suggests extensive tissue distribution. |
| Bioavailability | Oral: ~30-40% due to extensive first-pass metabolism (hepatic and possibly pulmonary). |
| Onset of Action | Oral: 15-30 minutes for antitussive effect. |
| Duration of Action | Oral: 3-6 hours; clinical effect may persist up to 8 hours at higher doses (100 mg). |
| Molecular Weight | 596.7 |
100 mg orally three times daily as needed for cough. Maximum 600 mg/day.
| Dosage form | CAPSULE |
| Renal impairment | No specific GFR-based dose adjustments established. Use with caution in severe renal impairment (CrCl <30 mL/min) due to uncertain excretion. |
| Liver impairment | No specific Child-Pugh-based adjustments established. Limited data in hepatic impairment; use with caution. |
| Pediatric use | Not recommended for use in children under 10 years due to risk of serious adverse effects. |
| Geriatric use | No specific dose adjustment required, but monitor for dizziness, sedation, and gastrointestinal effects due to increased sensitivity. |
| 1st trimester | Insufficient human data; animal studies not available. Avoid use in first trimester unless clearly needed. |
| 2nd trimester | Limited human data; caution advised. Use only if potential benefit outweighs risk. |
| 3rd trimester | Limited human data; potential risk of neonatal respiratory depression. Avoid use near term. |
Clinical note
Comprehensive clinical and safety monograph for TESSALON (TESSALON).
| Placental transfer | Likely crosses placenta due to low molecular weight (596.7 Da) but specific data lacking. |
| Breastfeeding | Not recommended due to potential for serious adverse effects in infants, including respiratory distress and aspiration. Alternative antitussive preferred. |
| Lactation Rating |
■ FDA Black Box Warning
None
| Common Effects | Application site irritation Increased risk of infection Headache Joint pain Injection site reactions pain swelling redness |
| Serious Effects |
Hypersensitivity to benzonatateInfants <10 years of ageUse of barbiturates in combination (increased CNS depression)
| Precautions | Accidental ingestion of capsules can lead to severe toxicity including cardiac arrest and death in children, especially those under 10 years of age., Hypersensitivity reactions including bronchospasm, laryngospasm, and anaphylaxis., Caution in patients with a history of drug allergy or allergic reactions to anesthetics of the ester type (e.g., tetracaine)., Avoid administering with food or water due to risk of oral mucosal anesthesia and choking. |
| Food/Dietary |
Loading safety data…
| L5 |
| Teratogenic Risk | Pregnancy Category C. First trimester: Limited human data; animal studies not conducted. Potential risk based on mechanism (sodium channel blockade) cannot be excluded. Use only if benefit outweighs risk. Second/third trimester: No adequate studies; fetal bradycardia and hypoxia possible with maternal toxicity. |
| Fetal Monitoring | Monitor maternal respiratory rate, oxygen saturation, and CNS status. Fetal monitoring (heart rate) recommended in third trimester if used near term due to risk of fetal bradycardia. |
| Fertility Effects | No human data on fertility impairment. In animal studies, no effects on fertility observed; however, relevance to humans unknown. |
| No specific food interactions have been established. Patients may take Tessalon with or without food. Avoid grapefruit juice as it may theoretically increase benzonatate levels due to CYP inhibition, though not well studied. |
| Clinical Pearls | Tessalon (benzonatate) is a non-narcotic oral antitussive that acts by anesthetizing the stretch receptors in the respiratory tract. Onset is within 15-30 minutes; duration is 3-8 hours. Do not exceed 200 mg per dose or 600 mg per day. Advise patients to swallow capsules whole (not to chew or dissolve) to avoid oral mucosal anesthesia and choking. Use with caution in patients with a history of drug or alcohol abuse. Benzonatate has a rare but serious risk of overdose, especially in children under 10 years; accidental ingestion can be fatal and requires immediate emergency treatment. |
| Patient Advice | Swallow the capsule whole; do not chew, crush, or dissolve it in the mouth because this can cause numbness or choking. · Take exactly as prescribed; do not take more than 200 mg per capsule form or more than 600 mg per day. · Do not drive or operate machinery until you know how this medicine affects you; it may cause dizziness, drowsiness, or blurred vision. · Keep this medication out of reach of children; accidental overdose can be fatal. · Seek emergency medical help if you experience severe reactions such as chest pain, confusion, hallucinations, or difficulty breathing. · Avoid alcohol and other CNS depressants while taking this medication. · If a dose is missed, take it as soon as remembered unless it is near the time of the next dose; do not double the dose. |