Benzonatate
Cough and cold medicines
Cough and cold medicines
A peripheral cough suppressant related to local anaesthetics; capsules are swallowed whole and kept away from children.
Quick facts
- Group
- Cough and cold medicines
- Target
- Stretch receptors of the airways, lungs and pleura
- Used for
- Symptomatic relief of cough
- Key effects
- Drowsiness and dizziness · Headache · Nasal congestion
- Monitor
- Cough relief · Swallowing problems or throat numbness
- ATC
- R05DB01
No doses: the clinician sets them by the current guideline.
Mechanism of action
Benzonatate is chemically related to ester local anaesthetics such as tetracaine. It acts peripherally, numbing the stretch receptors in the airways, lungs and pleura and so reducing the cough reflex at its source. If the capsule is chewed or sucked, it numbs the mouth and throat and can cause choking, laryngospasm and bronchospasm.
- Benzonatate reaches the airways and lungs
- It numbs the stretch receptors like a local anaesthetic
- Fewer signals reach the cough centre
- The cough reflex is damped at its source
Indications
- Symptomatic relief of cough Acute bronchitis →
Adverse effects
Common
- Drowsiness and dizziness
- Headache
- Nausea and constipation
- Nasal congestion, chills, skin rash
Contraindications
- Hypersensitivity to benzonatate or to para-aminobenzoic acid local anaesthetics (procaine, tetracaine)
- Young children (accidental ingestion risk)
Key interactions
- Other CNS depressants and psychoactive drugs
- Reports of confusion and visual hallucinations in combination
What is monitored
- Cough relief
- Swallowing problems or throat numbness
Administration and safety
- Capsules are swallowed whole: never chewed, sucked, crushed or broken
- Stored where children cannot reach them; the capsules look like candy
Pregnancy and breastfeeding
Human data are limited; it is used in pregnancy only if clearly needed.
Nursing care
- Teach to swallow capsules whole
- Warn about the danger to children and safe storage
- If the mouth or throat feels numb, the patient does not eat or drink until feeling returns
Pharmacokinetics
- Absorption
- Oral capsules
- Metabolism
- Hydrolysed by plasma esterases
- Onset and duration
- Within 15 to 20 minutes, lasting 3 to 8 hours
Test yourself
Think of the answer, then tap the question to see it.
Where does benzonatate act?
Peripherally, on stretch receptors in the airways, lungs and pleura.
Why must benzonatate capsules never be chewed?
Local anaesthesia of the mouth and throat can cause choking, laryngospasm and bronchospasm.
Which drug group is benzonatate chemically related to?
Ester local anaesthetics derived from para-aminobenzoic acid (procaine, tetracaine).
Connections
← Back to the class: Cough and cold medicines
Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: DailyMed - BENZONATATE capsule (DailyMed (U.S. National Library of Medicine), 2026); Benzonatate: MedlinePlus Drug Information (MedlinePlus (U.S. National Library of Medicine), 2017); ATCDDD - ATC/DDD Index (WHO Collaborating Centre for Drug Statistics Methodology, 2026).
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Representative model, for educational purposes only.