Levaquin vs. Zosyn: What's the difference?
- Levaquin (levofloxacin) and Zosyn (piperacillin and tazobactam) are antibiotics used to treat bacterial infections.
- Levaquin is used to treat bacterial infections of the sinuses, skin, lungs, ears, airways, bones, and joints; urinary infections; prostatitis; infectious diarrhea caused by E. coli, Campylobacter jejuni, and Shigella; obstetric infections, including mastitis (infection of the breast); inhalational anthrax exposure; and to prevent and treat plague caused by Yersinia pestis.
- Zosyn is used to treat bacterial infections such as pneumonia, appendicitis, pelvic inflammatory disease, E. coli cellulitis, and postpartum endometriosis.
- Side effects of Levaquin and Zosyn that are similar include nausea, vomiting, diarrhea, headache, constipation, difficulty sleeping, dizziness, stomach/abdominal pain, rash, and itching.
- Side effects of Levaquin that are different from Zosyn include gas. Levaquin and other fluoroquinolone antibiotics have been associated with tendinitis and even rupture of tendons, particularly the Achilles tendon.
- Side effects of Zosyn that are different from Levaquin include upset stomach, stool changes, fever, agitation, Candida (oral [thrush] or genital yeast infection), high blood pressure, chest pain, fluid retention (edema), anxiety, runny or stuffy nose, and shortness of breath.
What is Levaquin? What is Zosyn?
Levaquin (levofloxacin) is an antibiotic used to treat bacterial infections of the sinuses, skin, lungs, ears, airways, bones, and joints; urinary infections; prostatitis; infectious diarrhea caused by E. coli, Campylobacter jejuni, and Shigella; obstetric infections, including mastitis (infection of the breast); inhalational anthrax exposure; and to prevent and treat plague caused by Yersinia pestis. Levaquin stops multiplication of bacteria by preventing the reproduction and repair of their genetic material, DNA. It is in a class of antibiotics called fluoroquinolones that includes ciprofloxacin (Cipro), norfloxacin (Noroxin), ofloxacin (Floxin), trovafloxacin (Trovan), and lomefloxacin (Maxaquin).
Zosyn (piperacillin and tazobactam) is a combination of two antibiotics prescribed to treat a variety of bacterial infections such as pneumonia, appendicitis, pelvic inflammatory disease, E. coli cellulitis, and postpartum endometriosis. Piperacillin is an extended-spectrum penicillin antibiotic, but it can be destroyed by an enzyme produced by bacteria called beta lactamase. Tazobactam inhibits beta lactamase and prevents the destruction of piperacillin. Tazobactam is given with piperacillin to enhance the activity of piperacillin in eradicating bacterial infections.

QUESTION
Bowel regularity means a bowel movement every day. See AnswerWhat are the side effects of Levaquin and Zosyn?
Levaquin
Serious side effects and warnings include:
- Levofloxacin as well as other antibiotics in the fluoroquinolone class of antibiotics have been associated with tendinitis and even rupture of tendons, particularly the Achilles tendon.
- Fluoroquinolones have neuromuscular blocking activity and can worsen muscle weakness in individuals with myasthenia gravis.
The most frequently reported side effects are:
- Nausea or vomiting
- Diarrhea
- Headache
- Constipation
Less common side effects include:
- Difficulty sleeping
- Dizziness
- Abdominal pain
- Rash
- Abdominal gas
- Itching
Rare allergic reactions have been described are:
What are the serious side effects (adverse effects) of levofloxacin?
Possible serious side effects of levofloxacin include:
- Peripheral neuropathy
- Central nervous system effects
- Hypoglycemia
- Hyperglycemia
- Clostridium difficile-associated diarrhea
- Abnormal heartbeats
- Liver dysfunction
- Sun sensitivity
Other serious side effects and adverse events of levofloxacin include:
- Levofloxacin should be used with caution in patients with central nervous system diseases such as seizures, because rare seizures have been reported in patients receiving Levaquin.
- Levofloxacin should be avoided in children and adolescents less than 18 years of age, as safe use in these patients has not been established.
- Many antibiotics, including levofloxacin, can alter the normal bacteria in the colon and encourage overgrowth of a bacterium responsible for the development of inflammation of the colon, (C. difficile or pseudomembranous colitis). Patients who develop signs of pseudomembranous colitis after starting Levaquin (diarrhea, fever, abdominal pain, and possibly shock) should contact their doctor immediately.
- Patients taking Levofloxacin can develop sensitivity of the skin to direct sunlight (photosensitivity) and should avoid exposure to sunlight or use sunblock.
- Fluoroquinolones worsen low blood glucose levels when combined with sulfonylureas (for example, glyburide [Micronase, Diabeta, Glynase, Prestab]).
- Because of serious side effects associate with fluoroquinolones, they should not be used for treating uncomplicated urinary tract infections, acute bacterial exacerbation of chronic bronchitis or acute bacterial sinusitis unless there are no other alternatives.
Zosyn
Common side effects associated with piperacillin/tazobactam include:
- diarrhea,
- headache,
- constipation,
- nausea,
- difficulty sleeping,
- rash,
- vomiting,
- upset stomach,
- itching,
- stool changes,
- fever,
- agitation,
- Candida (oral [thrush] or genital yeast infeciton),
- high blood pressure,
- dizziness,
- stomach pain,
- chest pain,
- edema,
- anxiety,
- rhinitis, and
- shortness of breath.
Rare side effects occurring with a frequency of less than 1% are:
- agranulocytosis,
- hypersensitivity type reactions,
- anemia,
- canker sores,
- atrial fibrillation,
- bradycardia,
- cardiac arrest,
- cardiac arrhythmia,
- heart failure, and
- Clostridium difficile associated diarrhea.
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What is the dosage of Levaquin vs. Zosyn?
Levaquin
- The usual dose is 250-750 mg given once daily for 3-14 days depending on the type of infection.
- Anthrax is treated with 500 mg daily for 60 days.
- It is important to take oral formulations at least 2 hours before or 2 hours after any antacid or mineral supplement containing iron, calcium, zinc, or magnesium since these bind Levaquin and prevent its absorption into the body.
Zosyn
The usual total daily dose of piperacillin/tazobactam for adults is 3.375 g every six hours totaling 13.5 g (12.0 g piperacillin/1.5 g tazobactam). The usual duration of piperacillin/tazobactam treatment is from 7 to 10 days. Piperacillin/tazobactam should be administered by intravenous infusion over 30 minutes.
What drugs interact with Levaquin and Zosyn?
Levaquin
- Iron, calcium, zinc, or magnesium can attach to levofloxacin and other fluoroquinolones and prevent their absorption from the intestine into the blood. Therefore, products (for example, antacids) that contain iron, calcium, zinc, or magnesium should be taken at least 2 hours before or 2 hours after levofloxacin. Other drugs that contain these minerals and can similarly interact with levofloxacin include sucralfate (Carafate) and didanosine (Videx, Videx EC).
- Taking nonsteroidal anti-inflammatory drugs (NSAIDs) with levofloxacin may increase the risk of central nervous stimulation, resulting in over-excitation. There have been reports of changes in blood sugar (increases and decreases) in patients treated with fluoroquinolones and antidiabetic agents.
- Fluoroquinolones may increase the effect of warfarin (Coumadin, Jantoven).
Zosyn
- Probenecid may inhibit the renal tubular secretion (elimination via the kidneys) of piperacillin/tazobactam. This may cause higher, prolonged blood levels of piperacillin/tazobactam. The half-life of piperacillin is prolonged by 21% and the half-life of tazobactam by 71%.
- Piperacillin/tazobactam may inhibit platelet aggregation (formation of a blood clot) which may increase the risk for bleeding. Co-administration with blood thinning agents such as warfarin (Coumadin) requires close monitoring for signs or symptoms of bleeding.
- Piperacillin/tazobactam may prolong the neuromuscular blockade of vecuronium (Norcuron).
- Piperacillin/tazobactam may decrease the renal (kidney) elimination of methotrexate (Trexall). Patients on concurrent therapy with methotrexate should be monitored frequently for signs or symptoms of methotrexate toxicity.

SLIDESHOW
Bacterial Infections 101: Types, Symptoms, and Treatments See SlideshowAre Levaquin and Zosyn safe to use while pregnant or breastfeeding?
Levaquin
Levaquin is not recommended for use in pregnant women since Levaquin causes joint and bone deformities in juvenile animals of several species. Levaquin is excreted in breast milk. Mothers should decide whether to stop breastfeeding or discontinue Levaquin.
Zosyn
No evidence of fetal harm has been reported from use of piperacillin/tazobactam, piperacillin alone, and tazobactam alone in mice and rats (animal studies). Piperacillin/tazobactam is known to cross the placenta. Piperacillin/tazobactam is approved for the treatment of postpartum infections. As with all medications, piperacillin/tazobactam should be used cautiously in pregnancy. Potential benefits of treatment should be weighed against any potential risk to the fetus. Piperacillin and tazobactam is classified as FDA pregnancy risk category C.
Piperacillin is excreted into human milk in small amounts. Excretion of tazobactam in human milk has not been studied. Due to the lack of safety data, piperacillin/tazobactam should be used cautiously in females who are breastfeeding.
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Summary
Levaquin (levofloxacin) and Zosyn (piperacillin and tazobactam) are antibiotics used to treat bacterial infections. Levaquin is used to treat bacterial infections of the sinuses, skin, lungs, ears, airways, bones, and joints; urinary infections; prostatitis; infectious diarrhea caused by E. coli, Campylobacter jejuni, and Shigella; obstetric infections, including mastitis (infection of the breast); inhalational anthrax exposure; and to prevent and treat plague caused by Yersinia pestis. Zosyn is used to treat bacterial infections such as pneumonia, appendicitis, pelvic inflammatory disease, E. coli cellulitis, and postpartum endometriosis.
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