Oral Bacteria Dysbiosis in Patients with Linezolid-Induced Black Hairy Tongue: A Case Series.

Linezolid-induced black hairy tongue is a self-limiting benign disease that is rare. Here, we report three patients who developed black hairy tongue after linezolid treatment. The severe dysbiosis of oral bacterial communities was observed in all these patients. Proteobacteria was the most prevalent phylum (over 90%) at the black tongue stage. Furthermore, the dramatic oral bacterial alteration took a long time to reverse after the BHT resolved.