Monograph: |
Bromhexine hydrochloride
A white or almost white crystalline powder. Very slightly soluble in water ; slightly soluble in alcohol and in dichloromethane. Protect from light.
Stability studies of bromhexine and identification of its degradation products. It is estimated that under normal storage conditions bromhexine is stable for 10 years and aqueous solutions for 5 years.
Adverse Effects
Gastro - intestinal side - effects may occur occasionally with bromhexine and a transient rise in serum aminotransferase values has been reported. Other reported adverse effects include headache, dizziness, sweating, and skin rashes. Inhalation of bromhexine has occasionally produced cough or bronchospasm in susceptible subjects.
Precautions
Since mucolytics may disrupt the gastric mucosal barrier bromhexine should be used with care in patients with a history of peptic ulceration.. Care is also advisable in asthmatic patients. Clearance of bromhexine or its metabolites may be reduced in patients with severe hepatic or renal impairment.
Pharmacokinetics
Bromhexine hydrochloride is rapidly absorbed from the gastro - intestinal tract and undergoes extensive first - pass metabolism in the liver : its oral bioavailability is stated to be only about 20%. It is widely distributed to body tissues. About 85 to 90% of a dose is excreted in the urine mainly as metabolites. Ambroxol is a metabolite of bromhexine. Bormhexine is highly bound to plasma proteins. It has a terminal elimination half - life of up to about 12 hours. Bromhexine crosses the blood - brain barrier and small amounts cross the placenta.
Administration of bromhexine hydrochloride by mouth to healthy subjects produced peak plasma concentrations after about 1 hour. Only small amounts were excreted unchanged in the urine with a half - life of about 6.5 hours.
Uses and Administration
Bromhexine is a mucolytic used in the treatment of respiratory disorders associated with productive cough. Bromhexine is usually given by mouth in a dose of 8 to 16 mg of the hydrochloride three times daily. It has also been given by deep intramuscular or slow intravenous injection or inhaled as an aerosol solution.
Bromhexine has also been used orally and topically in the treatment of dry eye associated with abnormal mucus production. (see below)
Dry eye. Bromhexine has been used orally in the treatment of dry eye in sjogren's syndrome but results have been conflicting, and it appears to have no effect on tear secretion in healthy subjects. It has also been tried topically.
Respiratory - tract infection. USE WITH AN ANTIBACTERIAL.
Bromhexine has been shown to enhance the penetration of erythromycin into bronchial secretions and although bromhexine is often administered with other antibiotics as an adjuvant in the treatment of respiratory infections, few controlled studies appear to have been conducted to determine if any additional benefit is obtained. However, among those studies that have been carried out one reported that bromhexine improved the response to cephalexin and another that it improved the response to amoxycillin.
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