1 doctor weighed in:

What are the causes of black phlem?

1 doctor weighed in
Dr. Dennis Clifford
Internal Medicine - Pulmonary Critical Care

In brief: Several

Old blood, carbon from dust, carbon from smoke are all possible causes.

In brief: Several

Old blood, carbon from dust, carbon from smoke are all possible causes.
Dr. Dennis Clifford
Dr. Dennis Clifford
Thank
Get help from a real doctor now
Dr. Aaron Milstone
Board Certified, Internal Medicine - Pulmonology
23 years in practice
1M people helped
Continue
108,000 doctors available
Read more answers from doctors