 Linezolid was associated with significantly greater mortality than the comparator antibiotics . When data from all participants were pooled , the study found that 21 @.@ 5 % of those given linezolid died , compared to 16 % of those not receiving it . The difference was found to be due to the inferiority of linezolid in the treatment of Gram @-@ negative infections alone or mixed Gram @-@ negative / Gram @-@ positive infections . In participants whose infection was due to Gram @-@ positive bacteria alone , linezolid was as safe and effective as vancomycin . In light of these results , the FDA issued an alert reminding healthcare professionals that linezolid is not approved for the treatment of catheter @-@ related infections or infections caused by Gram @-@ negative organisms , and that more appropriate therapy should be instituted whenever a Gram @-@ negative infection is confirmed or suspected . 
