Dear sir,

Thank you for posting your query on XXXXXXX

Well looking into your problem i think you suffer from heavy bacterial infection specially pseudomonal infections give rise to green coloured sputum most commonly.

Black coloured sputum can be present in heavy smokers , in some fungal infections like mucormycosis , in persons who have worked in coal mines - Coal workers pneumoconiosis etc. but these seem to be less likely possibilty in your case.

Most probable thing in your case that some times food particles get stuck to mucus in throat then come along with cough sticking to phlegm as dark coloured particles specially when dark coloured foods like chocolate are eaten.

I advise you to see a pulmonologist , get a chest x XXXXXXX done ,get sputum routine microscopy with culture sensitivity . Malignancy needs to be excluded as you give history of weight loss .

Hope it answers your query.

Take care.

Dr Shruti

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