Zyvox medical uses
Linezolid (Zyvox) is a synthetic prescription antibiotic of the oxazolidinone class. It is used to treat serious bacterial infections, including pneumonia, skin infections, and infections that are resistant to other antibiotics.

It has a very high bioavailability allowing for rapid conversion from intravenous to oral therapy.

Zyvox works by inhibiting the initiation of bacterial protein synthesis - a mechanism of action that is unique to oxazolidinone class.

Zyvox dosage

Pneumonia and Complicated Skin Infections
Adults and adolescents 12 and older: 600 mg every 12 hours for 10 to 14 days.
Children (birth through 11 yr of age): 10 mg for every 2.2 pounds of body weight taken every 8 hours for 10 to 14 days.

Uncomplicated Skin Infections
Adults: 400 mg every 12 hours for 10 to 14 days.
Adolescents 12 years and older: 600 mg every 12 hours for 10 to 14 days.
Children under 5 years old: 10 mg for every 2.2 pounds of body weight taken every 8 hours for 10 to 14 days.
Children 5 to 11 years old: 10 mg for every 2.2 pounds of body weight taken every 12 hours for 10 to 14 days.

Enterococcus faecium Infections
Adults and adolescents 12 and older: 600 mg every 12 hours for 14 to 28 days.
Children (birth through 11 yr of age): 10 mg for every 2.2 pounds of body weight taken every 8 hours for 14 to 28 days.

Zyvox side effects

Most common side effects include the following: diarrhea, nausea, and vomiting. Less common side effects are headache, taste alterations, fungal infections, tongue discoloration, and abnormal findings on liver function tests.

Thrombocytopenia, a decrease in platelet count below 75% of normal or baseline, may be associated with the higher dose or treatment duration exceeding two weeks.

The FDA has recently reported cases of myelosuppression (anemia, leukopenia, and pancytopenia) warranting the monitoring of hematologic parameters and has issued a warning that myelosuppression is considered a potential side effect.

Precautions

If you have a condition called phenylketonuria and must avoid the amino acid phenylalanine, it's important to know that the liquid formulation of Zyvox contains this substance.
Lactic acidosis
Zyvox can cause lactic acidosis - very rare but potentially fatal side effect - especially if the treatment lasts longer than the recommended 28 days. It is caused by a buildup of lactic acid in the blood. Notify your doctor immediately if you experience repeated nausea and vomiting, dizziness, unusual tiredness or weakness, light-headedness, low body temperature, rapid breathing or trouble breathing, sleepiness, slow or irregular heartbeat, unexpected or unusual stomach discomfort, unusual muscle pain.
Myelosuppression (including anaemia, leucopenia, pancytopenia and thrombocytopenia) has been reported in patients receiving linezolid.
Peripheral and optic nerve damage
May occur primarily with long courses of treatment more than 28 days.

Zyvox drug interactions

Linezolid is a weak monoamine oxidase inhibitor (MAOI), and should not be used at the same time with other MAOIs.

The use with medications that increase concentrations of serotonin in the central nervous system may result in serotonin toxicity. These include triptans (e.g., sumatriptan, rizatriptan), SSRIs, tricyclic antidepressants, sibutramine, buspirone.

Food Interactions:

When taken with foods or beverages with high tyramine content, Zyvox can cause an increase in blood pressure. Common foods known to have high tyramine content include aged cheeses, soy sauce, fermented or air-dried meats, sauerkraut, tap beers, red wines.
Avoid consuming large amounts of tyramine rich foods

Pregnancy & Lactation

Pregnancy Risk Factor: C
Pregnancy category C. Caution is urged if used in breastfeeding mothers.

Breast-Feeding:
It is not known if linezolid is excreted in breast milk. The drug has 100% bioavailable which may increase the exposure to a nursing infant.

References:

1. U.S. Food and Drug Administration. Linezolid (Zyvox) U.S. Prescribing Information.