 When used for short periods, linezolid is a relatively safe drug. Common side effects of linezolid use (those occurring in more than 1 % of people taking linezolid) include diarrhea (reported by 3 – 11 % of clinical trial participants), headache (1 – 11 %), nausea (3 – 10 %), vomiting (1 – 4 %), rash (2 %), constipation (2 %), altered taste perception (1 – 2 %), and discoloration of the tongue (0.2 – 1 %). Fungal infections such as thrush and vaginal candidiasis may also occur as linezolid suppresses normal bacterial flora and opens a niche for fungi (so-called antibiotic candidiasis). Less common (and potentially more serious) adverse effects include allergic reactions, pancreatitis, and elevated transaminases, which may be a sign of liver damage. Unlike some antibiotics, such as erythromycin and the quinolones, linezolid has no effect on the QT interval, a measure of cardiac electrical conduction. Adverse effects in children are similar to those that occur in adults.
