Benzonatate - Indication, Dosage, Precautions, Side Effects, and Pharmacological Aspects

Introduction

Benzonatate is administered to treat coughs brought on by the flu or a cold. It should not be used in cases of chronic cough brought on by smoking, asthma, emphysema, or if there exists an unusually high production of mucus or phlegm. Benzonatate belongs to the class of drugs called antitussives, which are also known as cough suppressants. It functions by directly acting on the lungs and airways and decreasing the cough reflex. The cough center in the brain may also be affected by it.

For Patients:

What Are the Causes of Cough?

Numerous things, such as irritants, including smoking, strong odors, mold, dust, pollen, and pet dander, can cause coughing. Additionally, some drugs, like ACE inhibitors for blood pressure or mucus buildup, may cause it. Acute coughing can be caused by medical illnesses such as colds, the flu, bronchitis, sinusitis, pneumonia, and whooping cough. Persistent bronchitis, asthma, allergies, COPD (chronic obstructive pulmonary disease), throat diseases, postnasal drip, and cardiac problems like heart failure can all be causes of persistent coughing. These numerous reasons demonstrate how complicated coughing is and how crucial it is to find its underlying causes to treat it effectively.

How Is Benzonatate Used?

Benzonatate capsules and perles are available for oral consumption. The capsule has a liquid filling (perles), or it can be solid. It can be consumed at least three times a day as instructed. The patient should carefully read and follow the instructions on the drug label. In case of any confusion, they should consult their doctors or pharmacists. Benzonatate should be consumed as directed by the healthcare professional. The frequency and the amount of the drug should not be changed until the doctor advises. The patient should not break, dissolve, or cut the liquid-filled capsule before consuming it. It should not be sucked or chewed. Instead, swallow them as a whole. If the drug is chewed or sucked, it can cause the release of Benzonatate directly into the mouth resulting in a temporary anesthetic effect on the oral cavity, eventually leading to choking. If the mouth, tongue, throat, or face feels numb or tingly, avoid eating or drinking. Seek immediate medical attention if tingling or numbness sensations persist or worsen. The medicine should be kept away from children’s reach as deaths have been reported in cases of accidental consumption.

The daily recommended dose of Benzonatate is 600 mg (milligrams), and the recommended single dose is 200 mg. The drug should not exceed more than the recommended dose. If a single dose of Benzonatate is missed, the subsequent dose is taken at the next scheduled time. Two doses of Benzonatate should not be taken at the same time. The illness and treatment response will decide the drug dosage. Taking a dose over 200 milligrams at once is not advised. A higher drug dose than recommended will not make the cough disappear more quickly. However, doing so could have dangerous side effects.

Typically, this medication is taken as needed. If the patient regularly takes Benzonatate and forgets to take a particular dose, they should skip it and keep taking the medication as directed. A second dose should never be taken to compensate for the missed dose.

What Should the Patient Inform the Doctor Before Taking Benzonatate?

• Patients should inform the doctor about allergic reactions to Procaine, Tetracaine, Benzonatate, or other ingredients in Benzonatate capsules. They must also inform the doctor about allergy reactions to other medicines.

• Patients should inform the doctor if they are pregnant or thinking of conceiving a child or breastfeeding a child. Contact the doctor if pregnancy is positive during the treatment course of this medicine.

• Patients should inform the doctor if they take any prescribed or over-the-counter medications, vitamins, and herbal supplements. The doctor might change the dosage of medications or monitor the patient carefully for any side effects.

• Patients should inform the doctor or dentist if they are planning to undergo any surgery or dental surgery.

• Patients should inform the doctor if they have been prescribed other drugs that can make a person drowsy, like cough relievers containing Codeine or Hydrocodone. It also includes opioid pain relievers. The patient must also be informed if they have a habit of alcohol or marijuana consumption.

• Patients must also inform the doctors if they are taking drugs for sleep or anxiety disorders like Alprazolam, Lorazepam, and Zolpidem. They must also inform the doctors if they have prescribed antihistamines like Cetrizine and Diphenhydramine or muscle relaxants like Cyclobenzaprine or Carisoprodol.

How Is Benzonatate Stored and Disposed?

Keep the drug in its original container and ensure it is properly and tightly sealed. It is crucial to keep the drug out of children's reach and hence store it in a closed and child-proof container as they might be attracted to the design and appearance of the liquid-filled capsules. If ingested by children, there is always a risk of fatality in children. The drug should never be kept in a place where it is hot and humid, like in the bathrooms. It should always be stored at room temperature, away from heat and moisture.

All medications should be kept out of the sight and reach of children, as many of the packages (such as weekly pill containers and ones for ointments, drops for the eye, inhalers, and patches) are not child-resistant and are simple for children to open. Always secure safety caps and put the drug in a secure place right away. The drug should be placed up such that it remains out of the reach and sight of young children. This will prevent cases of accidental poisoning.

Unused and expired medications must be disposed of carefully to prevent pets, kids, and others from ingesting them. However, the drug must not be disposed of in the toilet. Instead, a medicine take-back program is the best way to eliminate the medication.

What Are the Side Effects of Benzonatate?

There are many side effects of Benzonatate. Doctors should be notified immediately if these symptoms appear and remain longer.

• Vomiting.

• Drowsiness.

• Burning sensation in the eyes.

• Constipation.

• Pain in the head.

• Stuffiness of the nose.

• Feeling cold.

• Dizziness.

The serious side effects of Benzonatate, which should be notified immediately to the doctors, are mentioned below.

• Skin rashes and hives.

• Chest numbness.

• A feeling of throat tightening.

• Hallucinations and confusion.

• Breathing difficulties and shortness of breath.

• Itching of the body.

For Doctors:

Description of Benzonatate

Benzonatate is an antitussive agent that belongs to the group of non-narcotic drugs, unlike most of the other drugs that are used for cough. It is administered orally.

• Chemical Formula - 2, 5, 8, 11, 14, 17, 20, 23, 26-nonaoxaoctacosan-28-yl p-(butyl amino).

• Molecular Formula - C30H53NO11.

• Molecular Weight - 603.7.

It is available in two forms: Perles and capsules. Perles are available with 100 mg Benzonatate content, and capsules are available with 200 mg Benzonatate content.

What Are the Pharmacological Aspects of Benzonatate?

Benzonatate exerts its peripheral action by numbing the stretch receptors in the lungs, pleura, and respiratory passages by reducing their activity. This, in turn, lessens the cough reflex at the point of origin. The drug starts working within 15 to 20 minutes, and its beneficial effects last three to eight hours. When used as directed, Benzonatate exerts no inhibiting impact on the respiratory center.

What Are the Indications and Contraindications for Benzonatate?

• Indication - Benzonatate is prescribed to treat cough symptoms.

• Contraindication - Any allergic reaction to Benzonatate or its ingredients.

Drug Precautions and Warnings:

• Precaution - Benzonatate has chemical similarities to the para-amino benzoic anesthetic group, which includes anesthetic drugs like Procaine and Tetracaine. Hence, the drug is known to have adverse effects on the CNS (central nervous system), which can be linked to its susceptibility to other drugs of the same class or its interconnection with concomitant drugs.

• Hypersensitivity - It has been reported that severe hypersensitivity reactions, including bronchospasm, laryngospasm, and cardiovascular collapse, may be brought on by the local anesthetic action, which is mainly caused by sucking or chewing the capsule as opposed to swallowing it. Intervention with vasopressor drugs and supportive measures are needed for severe reactions.

• Psychiatric Effects - Patients taking Benzonatate alongside other prescribed medications have also reported isolated cases of bizarre behavior, such as confusion and visual hallucinations.

• Accidental Consumption and Death - The drug should be kept away from children’s reach. Death as a result of accidental consumption of Benzonatate has been documented in children less than ten years of age. Within 15 to 20 minutes of ingestion, signs and symptoms of overdosing have been documented, and deaths have been documented within an hour. Upon accidental consumption, medical attention is needed immediately. Restlessness, tremors, convulsions, coma, and cardiac arrest are the possible signs and symptoms.

What Are the Adverse Reactions Associated With Benzonatate?

Below are the adverse reactions reported due to the use of Benzonatate.

• Hypersensitivity Reactions - Hypersensitivity reaction is caused due to the anesthetic effect caused due to Benzonatate as a result of chewing and sucking the tablets. It can lead to bronchospasm, laryngospasm, and collapse of the cardiovascular system.

• CNS Problem - The most common side effects seen are headache, dizziness, visual hallucinations, mental confusion, and sedation.

• Gastrointestinal Issue - The most commonly seen gastrointestinal (GI) problems are nausea, GI upset, and constipation.

• Dermatological Problems - Skin eruptions and pruritus are the most commonly seen adverse reactions related to the skin.

• Others - Congestion of the nose, burning sensation in the eyes, feeling of numbness in the chest, hypersensitivity, and chilly sensation are the other adverse reactions reported.

Overdosage

Both intentional and accidental overdoses have the potential to be fatal, especially in younger children (less than ten years of age). The medication shares several characteristics with other topical anesthetics and Tetracaine regarding pharmacology and toxicology. These medicines are typically well absorbed after consumption.

• Signs and Symptoms of Overdosing -The adverse reactions due to overdosing of the drug Benzonatate are visible within 15 to 30 minutes of its consumption. Chewing or dissolving capsules in the mouth will quickly cause oropharyngeal anesthesia, which could compromise the airway and result in choking. CNS stimulation may result in tremors and restlessness, which may progress to clonic convulsions and then profound CNS depression. Within an hour of ingestion, coma, convulsions, cardiac arrest, and cerebral edema, all resulting in death, have been documented.

Treatment of Overdosage

Medical attention and treatment should be taken immediately in case of overdosing. The gastric contents of the stomach should be removed. Activated charcoal slurry should be administered to the patient in abundance. Gag and cough reflexes are depressed even in conscious patients. Hence, it is necessary to be extra cautious to prevent aspiration of any drug administered orally or in gastric contents of the stomach. For the treatment of convulsions occurring during a drug overdose, a short-acting barbiturate is administered intravenously. It is precisely titrated for the smallest effective dose. The treatment for severe intoxication due to drug overdose must include intensive support to regulate the function of respiration and the cardiovascular-renal system. CNS stimulants should never be used to treat the symptoms of a drug overdose caused by Benzonatate.

How Is Benzonatate Supplied?

Perles come in bottles of 100 or 500 capsules by count.

• Perles - 100 mg comes in a bottle of 100 capsules whose NDC (National Drug Code) is 0069-0122-01. The letter “T” is imprinted.

• Perles - 300 mg comes in a bottle of 500 capsules whose NDC is 0069-0122-02. The letter “T” is imprinted on the capsule.

• Capsules - 200 mg- It comes in bottles of 200 capsules whose NDC is 0069-0124-01. The imprinted number on the capsule is 0698.

The drug is stored at a temperature of 25 degrees Celsius, and drug transportation is done at a temperature range of 15 to 27 degrees Celsius.

Drug Use in Specific Population

• Pregnancy - Benzonatate has not been used in animal reproduction studies. Additionally, it is unknown if Benzonatate, when given to a pregnant woman, can harm the fetus or affect a woman's ability to reproduce. Benzonatate should only be administered to a pregnant woman when necessary.

• Lactating Mothers - It is unknown whether Benzonatate gets eliminated in human milk. Traces and the presence of medicine have been noted in human milk, and hence, precautions should be taken while administering Benzonatate to a nursing mother.

• Pediatric Population - Studies for reporting safety and efficacy in children below ten years of age have not been conducted, and hence, safety data has not been established. Deaths in children below ten years of age due to accidental consumption have been documented, and hence, it should always be kept away from children’s reach.

• Carcinogenesis, Mutagenesis, and Fertility Impairment - No studies have been conducted to document the effect of Benzonatate on mutagenicity, carcinogenicity, and reproduction.