Zosyn (piperacillin and tazobactam)

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Brand Name

Zosyn {Pfizer}

Generic Name

piperacillin and tazobactam, pronounced pi PER a sil in and tay zoe BAK tam


What is Zosyn?

Zosyn is an antibiotic prescribed to treat a variety of different infections including those of the bones and joints, respiratory tract, gastrointestinal tract, skin, and severe vaginal infections. The combination of piperacillin and tazobactam makes this an effective antibiotic.

Zosyn may also be used for conditions that are not described in this medication guide.


Key Facts About Zosyn

Zosyn may cause bleeding, particularly if you have kidney disease or if you use certain medications. Tell your doctor if you are using any medication to prevent blood clots like alteplase (Activase), bivalirudin (Angiomax), clopidogrel (Plavix), dabigatran (Pradaxa), dipyridamole (Persantine, Aggrenox), enoxaparin (Lovenox), fondaparinux (Arixtra), heparin, tenecteplase (TNKase), ticlopidine (Ticlid), tinzaparin (Innohep) or warfarin (Coumadin, Jantoven).

Zosyn is in FDA pregnancy category B. Zosyn is not known to harm an unborn baby. You should tell your doctor if you are pregnant, or if you plan to become pregnant before you start to take Zosyn. You should not use Zosyn without telling your doctor if you are breastfeeding a baby, as Zosyn passes into breast milk.

Zosyn may cause diarrhea during treatment. This may be a side effect or the sign of a possible new infection. If you have diarrhea that is watery or bloody, you should stop taking Zosyn right away and call your doctor. Do not use any anti-diarrhea medications unless your doctor tells you to.


Before You Take Zosyn

You should not use Zosyn if you are allergic to piperacillin, tazobactam or any other penicillin antibiotic like: amoxicillin (Amoxil, Augmentin, Dispermox, Moxatag), ampicillin (Principen, Unasyn), dicloxacillin (Dycill, Dynapen), oxacillin (Bactocill), ticarcillin (Timentin) or penicillin (Bicillin L-A, PC Pen VK, Pfizerpen).

Tell your doctor if you have kidney disease or are on dialysis.

Let your doctor know if you have a bleeding or blood clotting disorder, an electrolyte imbalance like low levels of potassium in your blood or cystic fibrosis before taking Zosyn.

If you are on a low salt diet, or if you have a history of any type of allergy, especially to a cephalosporin antibiotic like cefdinir (Omnicef), cefprozil (Cefzil), cefuroxime (Ceftin) or cephalexin (Keflex) you should tell your doctor prior to taking Zosyn.


Zosyn Drug Interactions

You should inform your doctor if you are taking any of the following:

  • abciximab (ReoPro)
  • alteplase (Activase)
  • anagrelide (Agrylin)
  • antibiotics like kanamycin (Kantrex), neomycin (Mycifradin, Neo Fradin, Neo Tab), paromomycin (Humatin, Paromycin), streptomycin and tobramycin (Nebcin, Tobi)
  • argatroban (Acova)
  • bivalirudin (Angiomax)
  • cilostazol (Pletal)
  • clopidogrel (Plavix)
  • dabigatran (Pradaxa)
  • dalteparin (Fragmin)
  • dipyridamole (Persantine)
  • enoxaparin (Lovenox)
  • eptifibatide (Integrelin)
  • fondaparinux (Arixtra)
  • heparin
  • lepirudin (Refludan)
  • prasugrel (Effient)
  • probenecid (Benemid)
  • tenecteplase (TNKase)
  • ticlopidine (Ticlid)
  • tinzaparin (Innohep)
  • tirofiban (Aggrastat)
  • urokinase (Abbokinase)
  • warfarin (Coumadin, Jantoven)

Other drugs you take that are not listed may interact with Zosyn. You should tell your doctor about all of the medications you use. This includes prescription drugs, vitamins, supplements and herbal products, and over the counter medications. You should not begin taking a new medication without telling your doctor first.


Directions for Taking Zosyn

You should take Zosyn exactly as your doctor has prescribed you to. Do not use Zosyn in larger or smaller amounts, or for shorter or longer than recommended. Follow the directions on your prescription label exactly.

Zosyn is a medication that is injected into your vein through an IV. You may be taught to use the injections at home. You should not self-inject Zosyn if you do not fully understand how to give yourself the injection and properly dispose of the used needles, syringes, IV tubing, and other items used to inject the medicine.

The Zosyn IV infusion is typically done slowly. The IV infusion may take 30 minutes or longer to complete.

You should receive a dose of Zosyn for roughly 7-10 days, depending on your infection type. Your doctor will tell you how often you should be administered Zosyn.

If you are using the Zosyn injections at home you will need to mix this medication with a liquid or diluent before using it. Be sure that you understand how to properly mix and store Zosyn. You should not use Zosyn if it has changed colors or if you see particles in it. If this happens you should contact your doctor for a new prescription.

Prepare your dosage of Zosyn only when you are ready to use it, and not before.

The disposable needles should be used one time only. You must throw away all used needles in a puncture-proof container. If you do not own a puncture-proof container your pharmacist can tell you how to get one. Be sure to keep used needles and your puncture-proof container away from children and pets.

You can store unmixed Zosyn and the liquid diluent at a cool room temperature.

Any Zosyn that you have mixed in an IV bag must be used within 24 hours if you keep it at room temperature.

Mixed Zosyn in an infusion pump must be used within 12 hours, if you keep it at room temperature.

You may also store mixed Zosyn in an IV bag in the refrigerator for up to 7 days. Do not freeze Zosyn. Throw away any unused Zosyn mixture that has not been used within that time.

You can take Zosyn with or without food.

You must take Zosyn for the full amount of time your doctor has prescribed for you to take it. Your symptoms may improve before the infection is completely cleared, but you still need to complete your course of antibiotic treatment. Failure to do so may result in an increased risk of further infections that are resistant to antibiotics.

Zosyn can cause you to have unusual results with certain medical tests. Let any doctor know that you seeing know you are taking Zosyn.

If you miss a dose of Zosyn you should attempt to take the missed dose as soon as you remember. However, if it is almost time for your next scheduled dose do not take the missed dose in addition to your regular dose.

Zosyn Side Effects:

If you experience any of the following adverse effects you should stop taking Zosyn and seek medical help immediately:

  • allergic reaction that includes breathing difficulties, hives and swelling of your face, lips, throat or tongue
  • diarrhea that is watery or bloody
  • easy bruising or bleeding, including purple or red pinpoint spots under your skin.
  • fever with confusion, weakness, dark urine, pale or yellowed skin
  • flu symptoms with fever, chills and body aches
  • light headed and short of breath
  • seizures or convulsions
  • trouble concentrating with rapid heart rate
  • unusual bleeding, such as from your mouth, nose, rectum or vagina
  • white patches or sores inside your mouth or on your lips

Less serious Zosyn side effects may include:

  • agitation and anxiety
  • constipation
  • diarrhea
  • dizziness
  • insomnia
  • irritation, pain or swelling at the injection site
  • runny nose
  • skin rash and itching
  • upset stomach
  • vaginal itching or discharge

It should be noted that this is not a complete list of possible side effects of Zosyn. You should contact your physician for a complete list and medical advice regarding these effects.


Zosyn Description and Dosing

Zosyn is available in an intravenous infusion, to be administered over 30 minutes.

The usual total daily dose of Zosyn for adults is 3.375 g every six hours totaling 13.5 g (12.0 g piperacillin/1.5 g tazobactam).

Zosyn dosages vary for each individual based on their age, condition and situation. Your doctor will tell you the right dose of Zosyn for you to take. Do not change or alter your Zosyn dose without talking to your doctor first.

If you suspect that you have overdosed with the Zosyn you should seek emergency help immediately.


Ingredients in Zosyn

Zosyn is supplied in the following sizes:

Zosyn 2.25 g vial provides piperacillin sodium equivalent to 2 grams of piperacillin and tazobactam sodium equivalent to 0.25 g of tazobactam. Each vial contains 5.58 mEq (128 mg) of sodium.

Zosyn 3.375 g vial provides piperacillin sodium equivalent to 3 grams of piperacillin and tazobactam sodium equivalent to 0.375 g of tazobactam.

Zosyn 4.5 g vial provides piperacillin sodium equivalent to 4 grams of piperacillin and tazobactam sodium equivalent to 0.5 g of tazobactam.

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The information contained in this drug guide is intended as an educational resource only. This guide is not exhaustive and does not contain all available information about this drug.This guide is not intended as medical advice for individual conditions or treatment.

The information provided in this guide does not replace the need for the advice and services of medical professionals or the need for medical examination. Always talk to your physician or pharmacist before taking any prescription medication or over the counter drugs (including any supplements) or before making any changes to your treatment. Only your doctor, nurse or pharmacist can provide you with safe and effective advice regarding your drug treatment.

The use of the information in this guide is at your sole risk. This information is provided "AS IS" with no warranties to accuracy or timeliness.

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