You could try Bronchoforce as this is traditionally used for a mucus cough and I would also suggest cutting right down on dairy products such as milk and cheese as this can contribute to the problem in some people.
You may also find a high strength garlic supplement helpful if taken over time.
Dehydration can often be a factor too so do make sure that you are drinking plenty of plain water every day.
Do you have questions? Please feel free to ask.
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