Oral ZYVOX is 100% bioavailable13

In a study of 12 healthy participants, oral and IV ZYVOX both reached maximum plasma concentration levels within 2.2 hours

An open-label, phase 2, modified crossover study assessed the absolute bioavailability of oral ZYVOX compared to IV dosing. Twelve healthy male and female subjects aged 25 to 53 years each received a single 375-mg dose of ZYVOX as oral tablets while fasting. After 7 days, each subject received a 375-mg dose of ZYVOX as an IV infusion. (Adapted from Welshman et al. Biopharm Drug Dispos. 2001.13)

This phase 2 study was not conducted using the approved 600–mg q12h ZYVOX dose.
Please see full prescribing information.

Pharmacokinetic data do not necessarily correlate with clinical results.


  • ZYVOX mean plasma concentrations after oral and IV doses are almost identical in adults.13
  • When clinically appropriate, patients can seamlessly transition from IV ZYVOX to oral ZYVOX without reduction in efficacy or dosage adjustment.
  • When clinically appropriate, oral ZYVOX:
    • Allows for flexibility of treatment setting7
    • Does not require insertion of PICC* lines in certain patients27
    • Allows for patients to be discharged to home7

* Peripherally inserted central catheter



Important Safety Information

ZYVOX use is contraindicated in patients with known hypersensitivity to ZYVOX or any of the other product components.

ZYVOX should not be used in patients taking any medicinal product which inhibits monoamine oxidases A or B (e.g. phenelzine, isocarboxazid) or within 2 weeks of taking any such product.

Myelosuppression (including anemia, leukopenia, pancytopenia, and thrombocytopenia) has been reported in patients receiving ZYVOX. In cases where the outcome is known, when ZYVOX was discontinued, the affected hematologic parameters have risen toward pretreatment levels. Complete blood counts should be monitored weekly in patients who receive ZYVOX, particularly in those who receive ZYVOX for longer than two weeks, those with pre-existing myelosuppression, those receiving concomitant drugs that produce bone marrow suppression, or those with a chronic infection who have received previous or concomitant antibiotic therapy. Discontinuation of therapy with ZYVOX should be considered in patients who develop or have worsening myelosuppression.

Peripheral and optic neuropathy have been reported primarily in patients treated with ZYVOX for longer than the maximum recommended duration of 28 days. If patients experience symptoms of visual impairment, prompt ophthalmic evaluation is recommended. If peripheral or optic neuropathy occurs, the continued use of ZYVOX in these patients should be weighed against potential risks.

Spontaneous reports of serotonin syndrome including fatal cases have been reported with the co-administration of ZYVOX and serotonergic agents. Unless patients are carefully observed for signs and/or symptoms of serotonin syndrome or neuroleptic malignant syndrome-like (NMS-like) reactions, ZYVOX should not be administered to patients with carcinoid syndrome and/or patients taking any of the following medications: serotonin reuptake inhibitors, tricyclic antidepressants, serotonin 5-HT1 receptor agonists (triptans), meperidine, bupropion, or buspirone.

In some cases, a patient already receiving a serotonergic antidepressant or buspirone may require urgent treatment with ZYVOX. If alternatives to ZYVOX are not available and the potential benefits of ZYVOX outweigh the risks of serotonin syndrome or NMS-like reactions, the serotonergic antidepressant should be stopped promptly and ZYVOX administered. The patient should be monitored for two weeks (five weeks if fluoxetine was taken) or until 24 hours after the last dose of ZYVOX, whichever comes first. The patient should also be monitored for discontinuation symptoms of the antidepressant.

A mortality imbalance was seen in an investigational study in ZYVOX-treated patients with catheter-related bloodstream infections. ZYVOX is not approved and should not be used for the treatment of patients with catheter-related bloodstream infections or catheter-site infections. ZYVOX has no clinical activity against Gram-negative pathogens and is not indicated for the treatment of Gram-negative infections. It is critical that specific Gram-negative therapy be initiated immediately if a concomitant Gram-negative pathogen is documented or suspected.

Clostridium difficile associated diarrhea has been reported with use of nearly all antibacterial agents, including ZYVOX, and may range in severity from mild diarrhea to fatal colitis.

Unless patients are monitored for potential increases in blood pressure, ZYVOX should not be administered to patients with uncontrolled hypertension, pheochromocytoma, thyrotoxicosis and/or patients taking any of the following: directly and indirectly acting sympathomimetic, vasopressive, and dopaminergic agents.

Lactic acidosis has been reported with the use of ZYVOX. Patients receiving ZYVOX who develop recurrent nausea, vomiting, unexplained acidosis, or a low bicarbonate level should receive immediate medical evaluation.

Convulsions have been reported in patients treated with ZYVOX. In some of these cases, a history of seizures or risk factors for seizures was reported.

Postmarketing cases of symptomatic hypoglycemia have been reported in patients with diabetes mellitus receiving insulin or oral hypoglycemic agents when treated with ZYVOX, a reversible, non-selective MAO inhibitor. While a causal relationship between ZYVOX and hypoglycemia has not been established, diabetic patients should be cautioned of potential hypoglycemic reactions when treated with ZYVOX. If hypoglycemia occurs, a decrease in the dose of insulin or oral hypoglycemic agent, or discontinuation of oral hypoglycemic agent, insulin, or ZYVOX may be required.

Prescribing ZYVOX in the absence of a proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.

The most commonly reported adverse events (>2%) in adults across phase 3 clinical trials were diarrhea, nausea, and headache.


ZYVOX Indications

ZYVOX formulations are indicated in the treatment of the following infections caused by susceptible strains of the designated microorganisms. ZYVOX is not indicated for the treatment of Gram-negative infections. It is critical that specific Gram-negative therapy be initiated immediately if a concomitant Gram-negative pathogen is documented or suspected.

Nosocomial pneumonia caused by Staphylococcus aureus (methicillin-susceptible and -resistant strains) or Streptococcus pneumoniae.

Complicated skin and skin structure infections, including diabetic foot infections, without concomitant osteomyelitis, caused by Staphylococcus aureus (methicillin-susceptible and -resistant strains), Streptococcus pyogenes, or Streptococcus agalactiae. ZYVOX has not been studied in the treatment of decubitus ulcers.

Vancomycin-resistant Enterococcus faecium infections, including cases with concurrent bacteremia.

Uncomplicated skin and skin structure infections caused by Staphylococcus aureus (methicillin-susceptible only) or Streptococcus pyogenes.

Community-acquired pneumonia caused by Streptococcus pneumoniae, including cases with concurrent bacteremia, or Staphylococcus aureus (methicillin-susceptible strains only).

To reduce the development of drug-resistant bacteria and maintain the effectiveness of ZYVOX and other antibacterial drugs, ZYVOX should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.