Linezolid is an antibiotic used for the treatment of infections caused by Gram-positive bacteria that are resistant to other antibiotics. Linezolid is active against most Gram-positive bacteria that cause disease, including streptococci, vancomycin-resistant enterococci (VRE), and methicillin-resistant Staphylococcus aureus (MRSA). The main uses are infections of the skin and pneumonia although it may be used for a variety of other infections including drug-resistant tuberculosis. It is used either by injection into a vein or by mouth.When given for short periods, linezolid is a relatively safe antibiotic. It can be used in people of all ages and in people with liver disease or poor kidney function. Common side effects with short-term use include headache, diarrhea, rash, and nausea. Serious side effects may include serotonin syndrome, bone marrow suppression, and high blood lactate levels, particularly when used for more than two weeks. If used for longer periods it may cause  nerve damage, including optic nerve damage, which may be irreversible.As a protein synthesis inhibitor, linezolid works by suppressing bacterial protein production. This either stops growth or results in bacterial death. Although many antibiotics work this way, the exact mechanism of action of linezolid appears to be unique in that it blocks the initiation of protein production, rather than one of the later steps. As of 2014, bacterial resistance to linezolid has remained low. Linezolid is a member of the oxazolidinone class of medications.Linezolid was discovered in the mid-1990s, and was approved for commercial use in 2000.
Chemotherapy drugs associated with CIPN include thalidomide, the epothilones such as ixabepilone, the vinca alkaloids vincristine and vinblastine, the taxanes paclitaxel and docetaxel, the proteasome inhibitors such as bortezomib, and the platinum-based drugs cisplatin, oxaliplatin and carboplatin. and optic neuropathy, which is most common after several months of treatment and may also be irreversible. Although the mechanism of injury is still poorly understood, mitochondrial toxicity has been proposed as a cause; linezolid is toxic to mitochondria, probably because of the similarity between mitochondrial and bacterial ribosomes. Lactic acidosis, a potentially life-threatening buildup of lactic acid in the body, may also occur due to mitochondrial toxicity. Because of these long-term effects, the manufacturer recommends weekly complete blood counts during linezolid therapy to monitor for possible bone marrow suppression, and recommends that treatment last no more than 28 days. A more extensive monitoring protocol for early detection of toxicity in seriously ill patients receiving linezolid has been developed and proposed by a team of researchers in Melbourne, Australia. The protocol includes twice-weekly blood tests and liver function tests; measurement of serum lactate levels, for early detection of lactic acidosis; a review of all medications taken by the patient, interrupting the use of those that may interact with linezolid; and periodic eye and neurological exams in patients set to receive linezolid for longer than four weeks.The adverse effects of long-term linezolid therapy were first identified during postmarketing surveillance. Bone marrow suppression was not identified during Phase III trials, in which treatment did not exceed 21 days.