Bambuterol

Bambuterol is an Anti-Asthmatic agent belonging to the Long-Acting Beta 2 Adrenergic Receptor Agonist Pharmacological class.

Bambuterol is approved for the treatment of Bronchospasm, Emphysema, and Bronchial Asthma.

The common side effects associated with Bambuterol are Headache, palpitations, nausea, nervousness, anxiety, dry mouth, etc.

Bambuterol is available in the form of oral tablets and syrups.

Bambuterol is available in Turkey, Thailand, the U.S., India, and Japan.

Bambuterol belonging to the pharmacological class of Long-Acting Beta 2 Adrenergic Receptor Agonist, acts as an Anti-asthmatic/Bronchodilator therapeutic agent.

Bambuterol acts via a series of pathways causing increasing cAMP, thereby deactivating myosin light chain kinase and activating myosin light chain phosphate leading to smooth muscle relaxation in the bronchioles. Bambuterol hence leads to Bronchodilation of the smooth muscles and reverses bronchospasm. Bambuterol has a quick onset of action of minutes, and the duration of action lasts up to 13 hours or more.

Bambuterol is available in tablet and syrup form.

• Bambuterol oral tablet to be swallowed whole with water/liquid.

• Bambuterol oral syrup is to be taken orally.

Bambuterol can be used in the treatment of bronchospasm in patients more than 12 yrs old, bronchial asthma, and emphysema.

Bambuterol can help to relax bronchial smooth muscle leading to Bronchodilation and improving the patient's respiration.

Bambuterol is approved for use in the following clinical indications:

• Bronchospasm
• Emphysema
• Bronchial Asthma

Bambuterol should be used as maintenance therapy in asthma and other pulmonary diseases where bronchospasm is a complicating factor. Bambuterol is used once daily, preferably shortly before bedtime. The dose should be individualized.

• Adult Patients:

The recommended initial dose of Bambuterol is 10mg (10ml). The dose can be increased to 20mg (20ml) after 1-2 weeks, depending on the clinical effect of the initial dosing. In patients who have previously tolerated oral beta2- agonists well, the recommended initial dose is 20mg (20ml).

In patients with impaired renal function, the recommended initial dose is 5mg (5ml).

• Elderly:

10mg (10ml)or 20mg(20ml).

Patients 2-5 years:

The recommended normal dose is 10mg (10ml).

Patients 6-12 years: The recommended initial dose is 10mg (10ml). The dose can be increased to 20mg (20ml) after 1-2 weeks, depending on the clinical effect. Because of differences in kinetics, doses above 10mg (10ml) are not recommended in disoriented children.

Bambuterol should be used in the treatment of bronchospasm along with appropriate dietary restrictions:

• To maintain good respiratory health, smoking cessation is a must.

• Diet containing refined and high energy-dense foods, red and processed meat, added sugar, salt, preservatives, low antioxidants and vitamins, low fiber, food with a high glycemic index, and saturated and trans fat food needs to be restricted.

The dietary restriction should be individualized as per patient requirements.

Bambuterol may be contraindicated in the following:

• Hypersensitive to any components of the medication

The treating physician must closely monitor the patient and keep pharmacovigilance as follows:

• Deterioration of Asthmatic Condition:

There might be a deterioration of the asthma condition over a period of time. The increased usage of Bambuterol is a noted marker for the destabilization of the condition. Therefore a re-evaluation of the patient’s condition should be considered and the usage of anti-inflammatory agents such as corticosteroids should be considered.

• Anti-Inflammatory agent’s usage:

The use of Bambuterol alone might not be adequate to control asthmatic conditions, therefore early consideration of Corticosteroids should be taken.

Cardiovascular events:

Bambuterol has the potential of causing Myocardial Ischemia, Cardiac Arrest, changes in the ECG curve such as flattening of the T segment, prolongation of the Q-Tc segment,  and ST segment depression found to be associated with the beta 2 adrenergic agonist.

• Seizures:

Rare cases of seizures have been reported with the usage of Bambuterol.

• Hypokalemia:

Bambuterol causes a decrease in potassium levels which potentially produces adverse cardiac events. In acute asthma conditions, the use of Xanthine, Steroids, and Diuretics should be avoided or closely monitored as it may lead to hypoxia

• Diabetes Mellitus:

During Bambuterol usage, a patient with Diabetes Mellitus condition might suffer from hyperglycemia and will be unable to compensate in the condition of ketoacidosis

There is no sufficient scientific evidence traceable regarding the use and safety of bambuterol in concurrent use with alcohol.

Bambuterol or the components of the drug medication has not been known to be excreted in milk but a decision should be made by the treating physician whether to continue or discontinue this medication and should be only used if the benefits outweigh the risks.

• Pregnancy Category C:

There is no well-known established data on Bambuterol use in pregnant women, and fetal abnormalities have been reported in animal studies, but a decision should be made by the treating physician whether to continue or discontinue this medication, and should be only used if the benefits outweigh the risks.

No known interactions with food are noted.

The adverse reactions related to Bambuterol can be categorized as :

• Insomnia
• Trembling
• Muscle cramp
• Restlessness
• Headache
• Palpitations

The clinically relevant drug interactions of bambuterol are briefly summarized here

• Bambuterol prolongs the muscle-relaxing effect of suxamethonium or succinylcholine. This is due to the fact that plasma cholinesterase, which inactivates suxamethonium, is partly inhibited by bambuterol. This inhibition is dose-dependent and fully reversible.

• Beta-receptor blocking agents including eye drops, especially those which are non-selective, might totally or partly inhibit the effect of beta-stimulants. Hypokalemia may result from Bambuterol therapy and may be potentiated by the simultaneous treatment with xanthine derivatives, steroids, and diuretics.

The common side effects of Bambuterol include the following:

• Insomnia
• Trembling
• Muscle cramp
• Restlessness
• Headache
• Palpitations

The use of the molecule Bambuterol should be prudent in the following group of special populations:

• Breastfeeding Warning of Bambuterol:

Bambuterol or the components of the drug medication has not been known to be excreted in milk but a decision should be made by the treating physician whether to continue or discontinue this medication and should be only used if the benefits outweigh the risks.

• Pregnancy warning:

Pregnancy Category C

There is no well-known established data on Bambuterol use in pregnant women

No fetal abnormalities have been reported in animal studies, but a decision should be made by the treating physician whether to continue or discontinue this medication, and should be only used if the benefits outweigh the risks

• Use in labor or delivery
• Pediatric use

Bambuterol is indicated in patients less than 12 yrs. of age as there is enough clinical trials data. Usually, an oral dose of tablets or syrups is about 10 mg-20mg which is much lower than the adult doses.

The physician should be vigilant about the knowledge pertaining to the identification and treatment of overdosage of molecule Bambuterol.

No case of Bambuterol overdosage has been reported. However, it is likely that overdosing might result in high levels of terbutaline. The symptoms and signs as recorded after overdosage with Bambuterol are Headache, anxiety, tremor, tonic muscle cramps, palpitations, and tachycardia. A fall in blood pressure is sometimes found to occur after terbutaline overdosage. Laboratory findings state that hyperglycemia and lactacidosis sometimes occur.

A High dose of Bambuterol may cause hypokalemia as a result of the redistribution of potassium. Overdosage with Bambuterol is likely to cause a considerable inhibition of plasma cholinesterase, which may last for days.

Treatment of overdosage

• Usually, no treatment is required for the overdosage of Bambuterol.
• But in severe cases of overdosage, the following measures should be considered:
• Gastric lavage
• Activated charcoal.
• Determine acid-base balance
• Blood glucose and electrolytes
• Monitoring heart rate and rhythm and blood pressure.

The preferred antidote for overdosage with Bambuterol is using a cardioselective beta-blocking agent, but beta-blocking drugs should be used with caution in patients with a history of bronchospasm. If the beta2-mediated reduction in peripheral vascular resistance significantly contributes to the fall in blood pressure, a volume expander should be given.

Pharmacodynamics:

Bambuterol is a prodrug of the adrenergic beta-receptor agonist terbutaline.Bambuterol predominantly stimulates beta2-receptors and thus produces relaxation of bronchial smooth muscle, followed by inhibition of the release of endogenous spasmogens, inhibition of edema caused by endogenous mediators, and increased mucociliary clearance.

Pharmacokinetics:

• Absorption:

The absorption of oral doses of Bambuterol is found to be 20%. The absorption is not influenced by the simultaneous intake of food.

• Metabolism & Excretion:

Bambuterol is slowly metabolized via hydrolysis in the form of plasma cholinesterase and oxidation to active terbutaline.

About 1/3rd of the absorbed dose of bambuterol is metabolized in the intestinal wall and in the liver, mainly to intermediary metabolites. Out of the administered dose of bambuterol, about 10% of Bambuterol is converted to a metabolite, terbutaline in adults. Reduced clearance of terbutaline is found in children, but they also generate less terbutaline than adults. Therefore children aged 6-12 years should be given adult doses, whereas smaller children (2-5 years) usually need less. Maximum plasma concentration of the active metabolite terbutaline is found to be achieved within 2-6 hours. The effect duration lasts up to at least 24 hours. A Steady-state is reached after 4-5 days of treatment with Bambuterol. The plasma half-life of Bambuterol after oral administration is about 13 h. The plasma half-life of the actively generated metabolite, terbutaline is about 22 h. Bambuterol and its metabolites are mainly excreted via the kidneys as urine.

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1. https://www.pdr.net/drug-summary/Bambuterol-Sulfate-Tablets-Bambuterol-sulfate-1659#:~:text=Bambuterol sulfate is contraindicated in,been reported after Bambuterol administration.
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