Benzonatate (Tessalon Perles) is a prescription, non-narcotic antitussive medication used for the symptomatic relief of cough. It suppresses the cough reflex without containing opioid ingredients. Physicians prescribe it to manage coughs associated with respiratory conditions like the common cold or bronchitis.
How Benzonatate Works to Suppress Cough
Benzonatate functions as a local anesthetic, which is the basis for its cough-suppressing action. Its primary effect is peripheral, focusing on sensory nerves outside the central nervous system. The drug anesthetizes the stretch receptors found in the respiratory passages, lungs, and pleura. By reducing the activity of these receptors, benzonatate decreases the signals sent through the vagus nerve to the brain that trigger the cough reflex. The cough-relieving effect begins quickly, often within 15 to 20 minutes, and lasts for approximately three to eight hours.
Common Reactions to Benzonatate Use
Most individuals tolerate benzonatate well when taken as prescribed. However, like all medications, it may produce mild and temporary effects.
Frequently reported minor reactions involve the central nervous system. Patients may experience drowsiness, dizziness, or mild sedation, which can affect concentration and coordination. Headaches are also common.
Digestive system upsets are possible, including mild nausea, upset stomach, and constipation. Other infrequent effects include a chilly sensation or a stuffy nose.
Serious and Emergency Adverse Effects
The safety profile of benzonatate includes serious reactions requiring immediate medical attention.
Hypersensitivity reactions, while uncommon, can be severe and present as rash, itching, or hives. More severe allergic responses include life-threatening events such as bronchospasm, laryngospasm, or cardiovascular collapse.
Mental status changes have been observed in rare cases, including confusion, visual hallucinations, and unusual behavior. These psychological effects should prompt immediate cessation of the drug and medical consultation.
A specific danger arises if the capsule is broken, chewed, or sucked, releasing the potent anesthetic agent into the mouth and throat. This localized exposure causes rapid numbness in the mouth, tongue, and pharynx. This can lead to a feeling of choking or difficulty swallowing and breathing.
Accidental overdose represents the gravest risk, particularly in children younger than 10 years old. Ingestion of even one or two capsules by toddlers has resulted in fatal outcomes. Overdose symptoms manifest quickly, often within 15 to 20 minutes, and include restlessness, tremors, seizures, and rapid progression to coma or cardiac arrest.
Safe Administration and Precautions
The most important instruction for taking benzonatate is to swallow the liquid-filled capsules whole. The capsule must never be chewed, crushed, dissolved, or cut open, as this releases the anesthetic drug and causes numbness in the mouth and throat. If the mouth or throat feels numb after administration, avoid eating or drinking until the sensation subsides to prevent choking.
The drug should not be given to children under 10 years of age. Medication must be stored in a child-resistant container completely out of reach of children due to the high risk of fatal overdose. Benzonatate can increase the effects of other central nervous system depressants. Patients should use caution before combining this medication with alcohol or other sedating drugs, as this may intensify drowsiness or dizziness.