Bromhexine

Key facts

• Bromhexine (found in cough syrups and tablets) is a mucolytic. It breaks down the chemical bonds in thick mucus so a cough can clear it more effectively.
• It's for a wet, productive cough with thick phlegm, not a dry tickly cough; adults typically take it two to three times a day with water.
• Rare but serious skin reactions, including blistering rashes, have been reported. Stop it and seek care if your skin blisters or your mouth develops sores.
• See a doctor if your cough lasts more than a week, brings up blood, or comes with fever and breathlessness, since these need a diagnosis, not just mucus thinning.

What bromhexine treats

Bromhexine treats the thick, sticky mucus that builds up during a chest cold, acute bronchitis, or a flare of chronic bronchitis. By loosening that mucus it makes coughs more productive and, for many people, more comfortable. It does not treat the underlying infection or inflammation, so it does not replace antibiotics, inhalers, or other treatment a doctor prescribes for the cause of the cough.

How bromhexine works

Sticky mucus is held together by chemical bonds between long mucus-protein molecules. Bromhexine breaks these bonds, turning thick clumps into thinner, more fluid secretions that your cough reflex and the airway's tiny hairs (cilia) can move out of the lungs more easily.

Before you take it

• Avoid bromhexine if you have had an allergic reaction to it or to related mucolytics in the past.
• Tell your pharmacist if you have a history of stomach ulcers, since mucolytics can loosen the stomach's protective mucus layer too.
• Use caution with severe liver or kidney disease; your dose may need adjusting.
• If you're pregnant, trying to conceive, or breastfeeding, check with a health professional before use, since safety data in pregnancy are limited.

Side effects

Common effects are mild: nausea, stomach upset, headache, or loose stools.

Stop and seek urgent medical care for any of these:

• A blistering rash, peeling skin, or sores in the mouth or eyes.
• Facial or throat swelling, or difficulty breathing.
• Severe stomach pain, black stools, or vomiting blood.

Safety essentials

• Rare but serious skin reactions have been reported with bromhexine and related mucolytics. Any new rash, especially with blistering or mouth sores, means stop the medicine and get medical care the same day.
• Don't use it to mask a cough that won't go away, brings up blood, or comes with weight loss or night sweats; these need medical assessment, not more mucolytic.
• Buy only from a licensed pharmacy, since counterfeit cough medicines are a known problem in some markets.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.