Generic Name: Unasyn Brand Name(s): Generics only. No brands available.

Uses

What is Unasyn® (ampicillin/sulbactam) used for?

Unasyn® is a penicillin antibiotic. It works by blocking the bacteria’s cell wall growth, which kills the bacteria.

It is commonly used for treating infections caused by certain bacteria.

How should I take Unasyn® (ampicillin/sulbactam)?

Unasyn® is given as an injection at your doctor’s office, hospital, or clinic.

How do I store Unasyn® (ampicillin/sulbactam)?

Unasyn® is best stored at room temperature away from direct light and moisture. To prevent drug damage, you should not store Unasyn® in the bathroom or the freezer. There may be different brands of Unasyn® that may have different storage needs. It is important to always check the product package for instructions on storage, or ask your pharmacist. For safety, you should keep all medicines away from children and pets.

You should not flush Unasyn® down the toilet or pour them into a drain unless instructed to do so. It is important to properly discard this product when it is expired or no longer needed. Consult your pharmacist for more details about how to safely discard your product.

Precautions & warnings

What should I know before using Unasyn® (ampicillin/sulbactam)?

Before using this drug, tell your doctor if:

  • You are pregnant or breastfeeding. This is because, while you are expecting or feeding a baby, you should only take medicines on the recommendation of a doctor.
  • You are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, such as herbal and complementary medicines.
  • You have allergy with any of active or inactive ingredients of Unasyn® or other medications.
  • You have any other illnesses, disorders, or medical conditions.

Is it safe during pregnancy or breastfeeding?

There are no adequate studies in women for determining risk when using Unasyn® during pregnancy or while breastfeeding. Please always consult with your doctor to weigh the potential benefits and risks before taking Unasyn®. Unasyn® is pregnancy risk category B, according to the US Food and Drug Administration (FDA).

FDA pregnancy risk category reference below:

  • A=No risk
  • B=No risk in some studies
  • C=There may be some risk
  • D=Positive evidence of risk
  • X=Contraindicated
  • N=Unknown

Side effects

What side effects can occur from Unasyn® (ampicillin/sulbactam)?

Check with your doctor if any of these most common side effects persist or become bothersome:

  • Mild diarrhea
  • Pain, swelling, or redness at injection site

Seek medical attention right away if any of these severe side effects occur:

  • Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue)
  • Bloody stools or severe diarrhea
  • Chest pain
  • Chills
  • Fever
  • Severe nausea or vomiting
  • Stomach pain or cramps
  • Unusual bruising or bleeding
  • Vaginal irritation or discharge
  • Vein inflammation or tenderness
  • White patches in mouth

Not everyone experiences these side effects. There may be some side effects not listed above. If you have any concerns about a side-effect, please consult your doctor or pharmacist.

Interactions

What drugs may interact with Unasyn® (ampicillin/sulbactam)?

Unasyn® may interact with other drugs that you are currently taking, which can change how your drug works or increase your risk for serious side effects. To avoid any potential drug interactions, you should keep a list of all the drugs you are using (including prescription drugs, nonprescription drugs, and herbal products) and share it with your doctor and pharmacist. For your safety, do not start, stop, or change the dosage of any drugs without your doctor’s approval.

Products that may interact with this drug, such as:

  • Tetracyclines (e.g., doxycycline)
  • Probenecid
  • Allopurinol
  • Heparin
  • Methotrexate
  • Anticoagulants (e.g., warfarin)
  • Aminoglycosides (e.g., gentamicin), birth control pills, or live oral typhoid vaccine

Does food or alcohol interact with Unasyn® (ampicillin/sulbactam)?

Unasyn® may interact with food or alcohol by altering the way the drug works or increase the risk for serious side effects. Please discuss with your doctor or pharmacist any potential food or alcohol interactions before using this drug.

What health conditions may interact with Unasyn® (ampicillin/sulbactam)?

Unasyn® may interact with your health condition. This interaction may worsen your health condition or alter the way the drug works. It is important to always let your doctor and pharmacist know all the health conditions you currently have.

Especially if any of the followings apply to you:

  • Kidney problems
  • Mononucleosis (“mono”)
  • Liver problems or yellowing of the skin or eyes

Dosage

The information provided is not a substitute for any medical advice. You should ALWAYS consult with your doctor or pharmacist before using Unasyn® (ampicillin/sulbactam).

What is the dose of Unasyn® (ampicillin/sulbactam) for an adult?

Gynecologic Infections

The recommended dose is 1.5 g (1 g ampicillin + 0.5 g sulbactam) to 3 g (2 g ampicillin + 1 g sulbactam) IV/IM q6hr; not to exceed 12 g/day.

Intra-Abdominal Infections

The recommended dose is 1.5 g (1 g ampicillin + 0.5 g sulbactam) to 3 g (2 g ampicillin + 1 g sulbactam) IV/IM q6hr; not to exceed 12 g/day.

Skin & Skin Structure Infections

The recommended dose is 1.5 g (1 g ampicillin + 0.5 g sulbactam) to 3 g (2 g ampicillin + 1 g sulbactam) IV/IM q6hr; not to exceed 12 g/day.

Orbital Cellulitis

The recommended dose is 3 g (2 g ampicillin + 1 g sulbactam) IV q6hr.

Pelvic Inflammatory Disease

The recommended dose is 3 g (2 g ampicillin + 1 g sulbactam) IV q6hr.

Pneumonia

Aspiration or community acquired: The recommended dose is 1.5 g (1 g ampicillin + 0.5 g sulbactam) to 3 g (2 g ampicillin + 1 g sulbactam) IV q6hr for 5 or more days.

Hospital acquired: The recommended dose is 3 g IV q6hr for 5 or more days.

Pyelonephritis:

The recommended dose is 3 g (2 g ampicillin + 1 g sulbactam) IV q6hr for 14 days

Severe infection requiring hospitalization

The recommended dose is 1.5 g (1 g ampicillin + 0.5 g sulbactam) to 3 g (2 g ampicillin + 1 g sulbactam) IV q6hr for 5-7 days.

Enterococcus infection resistant to penicillin/susceptible to aminoglycosides:

The recommended dose is 3 g (2 g ampicillin + 1 g sulbactam) IV q6hr for 6 weeks if not aminoglycoside resistant; >6 weeks if aminoglycoside resistant.

HACEK infection:

The recommended dose is 3 g (2 g ampicillin + 1 g sulbactam) IV q6hr for 4 weeks.

What is the dose of Unasyn® (ampicillin/sulbactam) for a child?

Skin Infections

>1 year (<40 kg): The recommended dose is 200 mg/kg/day IV divided q6hr; not to exceed 14 days of therapy.

>1 year (>40 kg): The recommended dose is 1.5 g (1 g ampicillin + 0.5 g sulbactam) to 3 g (2 g ampicillin + 1 g sulbactam) q6hr; not to exceed 12 g/day.

Epiglottitis

Children and adolescents: The recommended dose is 100-200 mg ampicillin/kg/day IV divided q6hr.

Mild/Moderate Infection

  • >1 month-1 year: The recommended dose is 100-150 mg ampicillin/kg/day IV/IM divided q6hr.
  • >1 year: The recommended dose is 100-200 mg ampicillin/kg/day IV/IM divided q6hr.

Meningitis/Severe Infections

  • >1 month-1 year: The recommended dose is 200-300 mg ampicillin/kg/day IV/IM divided q6hr.
  • >1 year: The recommended dose is 200-400 mg ampicillin/kg/day IV/IM divided q6hr.

Peritonsillar and Retropharyngeal Abscess

  • Children and adolescents: The recommended dose is 200 mg ampicillin/kg/day IV divided q6hr.

How is Unasyn® (ampicillin/sulbactam) available?

Unasyn® is available in the following dosage forms and strengths:

  • 5g (ampicillin 1g/sulbactam 0.5g)
  • 3g (ampicillin 2g/sulbactam 1g)
  • 15g (ampicillin 10g/sulbactam 5g)

What should I do in case of an emergency or overdose?

In case of an emergency or an overdose, call your local emergency services or go to your nearest emergency room.

What should I do if I miss a dose?

If you miss a dose of Unasyn®, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and take your regular dose as scheduled. Do not take a double dose.

Hello Health Group does not provide medical advice, diagnosis or treatment.

Sources

Review Date: June 8, 2017 | Last Modified: June 8, 2017

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