Zyvox works to stop bacteria growth. It belongs to a drug class known as oxazolidinone antibiotics. However, Zyvox is also a monoamine oxidase inhibitor (MAOI). MAOIs are associated with certain drug and food interactions.

It is available orally as a tablet and as a suspension (liquid). It is also available as an injection. This article will focus on the oral forms of Zyvox.

What Is Zyvox Used For?

The Food and Drug Administration (FDA) approved Zyvox for various bacterial infections, including:

Brand Name(s): Zyvox

Administration Route: Oral

Drug Availability: Prescription

Therapeutic Classification: Antibiotic

Available Generically: Yes

Controlled Substance: N/A

Active Ingredient: Linezolid

Dosage Form(s): Tablet, powder for suspension

Nosocomial (acquired in a healthcare facility such as a hospital) pneumonia caused by bacteria called Staphylococcus aureus (methicillin-susceptible and methicillin-resistant) or Streptococcus pneumoniae. Community-acquired pneumonia (acquired outside of a healthcare setting) caused by bacteria called Streptococcus pneumoniae, or Staphylococcus aureus (methicillin-susceptible) Complicated and uncomplicated infections of the skin and skin structure, including diabetic foot infections Infections caused by a bacteria called Enterococcus faecium that is resistant to an antibiotic called vancomycin

Zyvox does not work for viral infections such as the common cold, flu, or COVID-19. Zyvox is only used to treat certain types of bacterial infections. 

How to Take Zyvox

Before taking Zyvox, read the patient information that comes with your prescription. Consult your healthcare provider if you have any questions. 

Take Zyvox exactly as directed for the full prescribed length of time. Do not stop taking your medication before your treatment regimen is complete unless your healthcare provider tells you to do so. Skipping doses or stopping the medicine too soon can make your infection resistant to the antibiotic.

The oral forms of Zyvox (tablet or suspension) can be taken with or without food.

Before taking the liquid suspension, gently mix (do not shake) the suspension by turning the bottle upside down three to five times. Measure the prescribed dose with an oral dosing syringe or another medication-measuring device. Do not use kitchen tools to measure medication.

Storage

Store Zyvox at room temperature (68 degrees to 77 degrees Fahrenheit), away from heat, direct light, and moisture. Keep Zyvox in its original labeled container and out of the reach of children and pets. Do not freeze it. If you use the suspension form, discard any remaining liquid after 21 days.

Off-Label Uses

Healthcare providers sometimes prescribe Zyvox for off-label uses, meaning for conditions not specifically indicated by the FDA. 

Oral Zyvox may be prescribed off-label for:

Endocarditis  Pulmonary tuberculosis that is resistant to other drugs Septic arthritis Prosthetic joint infections Spinal implant infections Central nervous system (CNS) infections such as meningitis

What Are the Side Effects of Zyvox?

This is not a complete list of side effects and others may occur. A healthcare provider can advise you on side effects. If you experience other effects, contact your pharmacist or a healthcare provider. You may report side effects to the FDA at fda.gov/medwatch or 1-800-FDA-1088.

Common Side Effects

The most common side effects of Zyvox are:

Stomach problems like pain, nausea, vomiting, and diarrheaHeadacheDizziness RashLow platelet countsLow red blood cell counts

Severe Side Effects

Call your healthcare provider right away if you have serious side effects. Call 911 if your symptoms feel life-threatening or think you’re having a medical emergency. 

Serious side effects can include the following:

Hypersensitivity reaction or anaphylaxis Severely high blood pressure (hypertensive crisis) Angioedema (swelling under the skin) Stevens-Johnson syndrome or toxic epidermal necrolysis (life-threatening skin reactions with symptoms of red and purple rash, fever, sore throat, burning eyes, and blistering, peeling skin) Superinfection (getting a second infection in addition to the first infection) Antibiotic-associated diarrhea (severe diarrhea that can be life-threatening): This may occur up to two months after the antibiotic treatment is complete. Low red and white blood cell counts Low platelets  Low blood sugar Peripheral neuropathy (numbness and weakness in the hands and feet) Optic neuropathy (damage to the optic nerve of the eye) Vision loss or changes Serotonin syndrome (a life-threatening reaction caused by the buildup of too much serotonin) QT prolongation/torsades de pointes (heart rhythm conditions) Hyponatremia (low sodium levels) Syndrome of inappropriate antidiuretic hormone secretion (also known as SIADH)

Long-Term Side Effects

In some cases, Zyvox can cause long-term or delayed side effects. Some effects are mild, such as tongue or tooth discoloration or vitamin B6 deficiency. 

Other long-term or delayed side effects are considered moderate, such as:

Low platelet levelsLow red blood cell levelsFungal infectionsAntibiotic-associated diarrheaNumbness and weakness of the hands and feet

More severe long-term or delayed side effects can include:

Serotonin syndromeSeizuresSevere skin reactionsElectrolyte imbalanceDamage to the optic nerve in the eye

How Much Zyvox Should I Take?

Modifications

In certain cases, your healthcare provider may adjust your dosage of Zyvox or monitor you more closely while taking this medication.

If you experience a serious side effect, you or your healthcare provider may send a report to the FDA’s MedWatch Adverse Event Reporting Program or by phone (800-332-1088).

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

For oral dosage forms (suspension or tablets): For bacterial infections: Adults and children 12 years of age and older—400 or 600 milligrams (mg) every 12 hours. Children younger than 12 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 10 milligrams (mg) per kilogram (kg) of body weight every 8 or 12 hours as determined by your doctor.

ChildrenZyvox can be used in children. The healthcare provider may determine dosing based on the child’s age and weight.

Pregnancy Consult your healthcare provider if you are pregnant or plan to become pregnant. The prescribing information states that Zyvox should be used with caution in pregnancy. There is not enough data on the use of Zyvox during pregnancy in humans. Some data from animal studies (conducted in rats, mice, and rabbits) showed that Zyvox may potentially harm or cause death to the fetus. However, this has not been seen in the limited amount of human data available.

BreastfeedingPeople who are breastfeeding should consult their provider for medical advice before taking Zyvox.

Older AdultsIn clinical studies, Zyvox was similarly effective and safe in older (aged 65 years and above) and younger adults.1 No dosage adjustment is required in older individuals. However, some older adults experience greater sensitivity to certain medications. Consult your healthcare provider for medical guidance.

Kidney or Liver ProblemsPeople with kidney or liver problems should consult their healthcare provider for medical guidance before using Zyvox.

Missed Dose

If you miss a dose of Zyvox, take it as soon as you can. Skip the missed dose if it is almost time for the next dose. Do not take two doses together.

Overdose: What Happens If I Take Too Much Zyvox?

If you take more than the prescribed dose of Zyvox, contact your healthcare provider for the next steps. In the event of an overdose, you may need supportive care or hemodialysis for the removal of the drug.

Precautions

What Are Reasons I Shouldn’t Take Zyvox?

Zyvox is not appropriate for everyone. Avoid taking Zyvox if you are allergic to Zyvox or any of its ingredients or have taken monoamine oxidase inhibitors (MAOIs) in the last 14 days.

If someone collapses, has a seizure, has trouble breathing, or can’t wake up after taking too much Zyvox, call 911 immediately.

If your or your child’s symptoms do not improve within 28 days or if they become worse, check with your doctor.

You should not use this medicine if you or your child have used an MAO inhibitor (MAOI), including isocarboxazid, phenelzine, Eldepryl®, Marplan®, Nardil®, or Parnate® within the past 14 days. Also, do not use this medicine if you or your child are also using the following medicines: buspirone (Buspar®), dobutamine (Dobutrex®), dopamine (Intropin®), epinephrine (Adrenalin®), norepinephrine (Levophed®), cold medicines or decongestants (eg, phenylpropanolamine, pseudoephedrine, or Sudafed®), medicine to treat depression (eg, amitriptyline, bupropion, doxepin, fluoxetine, nortriptyline, paroxetine, Celexa®, Effexor®, Elavil®, Lexapro®, Paxil®, or Zoloft®), medicine to treat migraine headaches (eg, sumatriptan, zolmitriptan, Axert®, Imitrex®, or Zomig®), or narcotic pain medicines (eg, meperidine, Demerol®).

Linezolid can lower the number of white blood cells in your blood temporarily, increasing the chance of getting an infection. It can also lower the number of platelets, which are necessary for proper blood clotting. If this occurs, there are certain precautions your doctor may ask you to take, especially when your blood count is low, to reduce the risk of infection or bleeding:

If you can, avoid people with infections. Check with your doctor immediately if you think you or your child are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination. Check with your doctor immediately if you notice any unusual bleeding or bruising, black, tarry stools, blood in the urine or stools, or pinpoint red spots on your skin.

This medicine may cause infertility to men. Talk with your doctor before using this medicine if you plan to have children.

This medicine may cause diarrhea, and in some cases it can be severe. It may occur 2 months or more after you stop taking this medicine. Do not take any medicine to treat diarrhea without first checking with your doctor. If you have any questions or if mild diarrhea continues or gets worse, check with your doctor.

You may develop low blood sugar while you or your child are taking this medicine. You may feel weak, drowsy, confused, anxious, or very hungry. You may have trouble seeing or have a headache that won’t go away. Ask your doctor what you should do if this happens. Some things that can lead to low blood sugar are exercising more than normal or waiting too long to eat.

This medicine may cause a serious reaction called lactic acidosis (build-up of acid in the blood). Call your doctor right away if you or your child feel very tired, weak, or nauseated, if you vomit or have trouble breathing, or if you feel lightheaded or fainting.

This medicine may cause serious condition called serotonin syndrome when taken with certain medicines, including medicines to treat depression (SSRIs) or narcotic pain medicines. Check with your doctor first before taking any other medicines. Contact your doctor right away if you or your child experience agitation, confusion, diarrhea, fever, overactive reflexes, poor coordination, restlessness, shivering, sweating, or trembling or shaking.

Check with your doctor right away if blurred vision, difficulty in reading, or any other change in vision occurs during treatment with this medicine. Your eyes may need to be checked by an ophthalmologist (eye doctor).

When taken with certain foods or drinks, linezolid can cause an increase in blood pressure. To avoid this, do not eat large amounts of foods or drink beverages that have a high tyramine content (most common in foods that are aged, fermented, pickled, or smoked to increase their flavor, including aged cheeses, air-dried, fermented, or smoked fish, meat, or poultry, sauerkraut, soy sauce, red wine, or tap beer). If a list of these foods and beverages is not given to you, ask your doctor to provide one.

Check with your doctor right away if you have agitation, coma, confusion, decreased urine output, depression, dizziness, headache, hostility, increased thirst, irritability, lethargy, muscle pain or cramps, muscle twitching, nausea or vomiting, rapid weight gain, seizures, stupor, swelling of the face, ankles, or hands, or unusual tiredness or weakness. These may be symptoms of hyponatremia (low sodium levels in the blood) or syndrome of inappropriate antidiuretic hormone (SIADH).

Do not take other medicines unless thy have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

You should also stay away from foods high in tyramine when taking Zyvox, such as aged cheeses, cured/smoked/processed meats, pickled or fermented foods, and beer.

Additionally, the liquid form of Zyvox contains phenylalanine, which can be harmful to people with phenylketonuria (PKU). Notify your healthcare provider if you have PKU. 

Before taking Zyvox, tell your healthcare provider about all of your medical conditions and medications you take, including prescription and over-the-counter (OTC) drugs, vitamins, and supplements. This will ensure your provider can prescribe Zyvox safely.

What Other Medications Interact With Zyvox?

It is important to remember to avoid taking MAOIs with Zyvox. These medications should be avoided within 14 days of starting Zyvox. MAOI medications include:

Marplan (isocarboxazid)Nardil (phenelzine)Azilect (rasagiline)Eldepryl, Zelepar (selegiline)Parnate (tranylcypromine)

Other medications that should not be taken with Zyvox include:

Strattera (atomoxetine)  Bupropion Buspar, Vanspar (buspirone)  Nydrazid (isoniazid)  Eskalith or Lithobid (lithium)  Remeron (mirtazapine)  Opioid pain medications such as codeine, morphine, oxycodone, and tramadol Orap (pimozide)  Pseudoephedrine  Serotonin and norepinephrine reuptake inhibitor (SNRI) antidepressants including Cymbalta (duloxetine) and Effexor XR (venlafaxine) Selective serotonin reuptake inhibitor (SSRI) antidepressants including Lexapro (escitalopram), Prozac (fluoxetine), and Luvox (fluvoxamine) Stimulants such as amphetamine, dexmethylphenidate, and dextroamphetamine St. John’s Wort Trazodone  Tricyclic antidepressants such as amitriptyline, clomipramine, and desipramine Triptans for migraine such as rizatriptan, sumatriptan, and zolmitriptan

What Medications Are Similar?

Like Zyvox, Sivextro is another oxazolidinone antibiotic. It contains the ingredient tedizolid.

Vancomycin is another antibiotic that is used for serious infections, as well as antibiotic-associated diarrhea.  

There are many other classes of oral antibiotics, which can be used for various bacterial infections. Some classes of antibiotics and examples of drugs in each class include:

Cephalosporin antibiotics such as Ceftin (cefuroxime), Duricef (cefadroxil), Keflex (cephalexin), and Omnicef (cefdinir) Lincosamide antibiotics such as clindamycin Macrolide antibiotics such as Biaxin (clarithromycin), Zithromax (azithromycin), and erythromycin Penicillin antibiotics: Augmentin (amoxicillin and clavulanic acid), penicillin, amoxicillin Quinolone antibiotics such as levofloxacin and ciprofloxacin Sulfa antibiotics: Bactrim (trimethoprim/sulfamethoxazole) Tetracycline antibiotics such as doxycycline, minocycline, and tetracycline

Your healthcare provider will prescribe the antibiotic expected to work against the bacteria that is causing the infection. 

This list is a list of antibiotic drugs also prescribed for bacterial infections. It is NOT a list of drugs recommended to take with Zyvox. Ask your pharmacist or a healthcare provider if you have questions.

How Can I Stay Healthy While Taking Zyvox?

Before taking Zyvox, discuss your medical conditions and history with your healthcare provider.

Many drugs interact with Zyvox. Tell your healthcare provider about your medications, including prescription and OTC drugs, vitamins, and supplements. This helps ensure that Zyvox will be prescribed safely and that your healthcare provider can monitor you appropriately while you take Zyvox. Check with your healthcare provider before you start or stop any other medications. Notify them if you start to have any vision changes. 

Zyvox may lower your blood sugar. If you have diabetes, your healthcare provider may adjust your insulin or diabetes medication dose. Monitor your blood sugar carefully and notify your healthcare provider of hypoglycemic (low blood sugar) episodes. Be sure to have fast-acting carbohydrates (such as glucose tablets) with you. Also, keep glucagon (injection or nasal spray) on hand in case of a low blood sugar emergency.