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Brand Name(s):

  • Unasyn® (as a combination product containing Ampicillin, Sulbactam)

WHY is this medicine prescribed?

The combination of ampicillin and sulbactam injection is used to treat certain infections caused by bacteria, including infections of the skin, female reproductive organs, and abdomen (stomach area). Ampicillin is in a class of medications called penicillin-like antibiotics. It works by stopping the growth of bacteria. Sulbactam is in a class of medications called beta-lactamase inhibitors. It works by preventing bacteria from destroying ampicillin.

Antibiotics such as ampicillin and sulbactam injection will not work for colds, flu, or other viral infections. Using antibiotics when they are not needed increases your risk of getting an infection later that resists antibiotic treatment.

HOW should this medicine be used?

Ampicillin and sulbactam injection comes as a powder to be mixed with liquid and injected intravenously (into a vein) or intramuscularly (into a muscle) every 6 hours (4 times daily). The length of treatment depends on the type of infection you have. Your doctor will tell you how long to use ampicillin and sulbactam injection. After your condition improves, your doctor may switch you to another antibiotic that you can take by mouth to complete your treatment.

You may receive ampicillin and sulbactam injection in a hospital, or you may use the medication at home. If you will be using ampicillin and sulbactam injection at home, your health care provider will show you how to use the medication. Be sure that you understand these directions, and ask your healthcare provider if you have any questions.

You should begin to feel better during the first few days of treatment with ampicillin and sulbactam injection. If your symptoms do not improve or if they get worse, call your doctor. If you still have symptoms of infection after you finish ampicillin and sulbactam injection, tell your doctor.

Use ampicillin and sulbactam injection until you finish the prescription, even if you feel better. If you stop using ampicillin and sulbactam injection too soon or if you skip doses, your infection may not be completely treated and the bacteria may become resistant to antibiotics.

Are there OTHER USES for this medicine?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What SPECIAL PRECAUTIONS should I follow?

Before receiving ampicillin and sulbactam injection,

  • tell your doctor and pharmacist if you are allergic to ampicillin; sulbactam; penicillin antibiotics; cephalosporin antibiotics such as cefaclor, cefadroxil, cefazolin (Ancef, Kefzol), cefdinir, cefditoren, cefepime (Maxipime), cefixime (Suprax), cefotaxime (Claforan), cefotetan, cefoxitin (Mefoxin), cefpodoxime, cefprozil, ceftaroline (Teflaro), ceftazidime (Fortaz, Tazicef, in Avycaz), ceftibuten, ceftriaxone,cefuroxime (Ceftin, Zinacef), and cephalexin (Keflex); any other medications; or any of the ingredients in ampicillin and sulbactam injection. Ask your pharmacist for a list of the ingredients.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: allopurinol (Aloprim, Lopurin, Zyloprim), or probenecid (Probalan, in Col-Probenecid). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have or have ever had liver disease, especially if it occurred after using a penicillin antibiotic. Your doctor may tell you not to use ampicillin and sulbactam injection.
  • tell your doctor if you have mononucleosis (a virus also called 'mono'), and if you have or have ever had allergies, asthma, hives, hay fever, or kidney disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while using ampicillin and sulbactam injection, call your doctor.

What SPECIAL DIETARY instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What SIDE EFFECTS can this medicine cause?

Ampicillin and sulbactam injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • diarrhea
  • nausea
  • vomiting
  • redness, irritation, or pain at the injection site

Some side effects can be serious. If you experience any of these symptoms, stop using ampicillin and sulbactam injection and call your doctor immediately or get emergency medical treatment:

  • rash
  • peeling or blistering of the skin
  • itching
  • hives
  • difficulty breathing or swallowing
  • wheezing
  • swelling of the eyes, face, mouth, lips, tongue, throat, hands, feet, ankles or lower legs
  • hoarseness
  • severe diarrhea (watery or bloody stools) that may occur with or without fever and stomach cramps (may occur up to 2 months or more after your treatment)
  • yellowing of the skin or eyes
  • pain in the upper right part of your stomach
  • dark urine
  • a return of fever, cough, sore throat, chills, and other signs of infection

Ampicillin and sulbactam injection may cause other side effects. Call your doctor if you have any unusual problems while using this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( Web Site ) or by phone (1-800-332-1088).

What should I do in case of OVERDOSE?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at Web Site. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

  • seizures

What OTHER INFORMATION should I know?

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to ampicillin and sulbactam injection.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are using ampicillin and sulbactam injection. If you are diabetic, use Clinistix or TesTape (not Clinitest) to test your urine for sugar while using this medication.

Ask your pharmacist any questions you have about ampicillin and sulbactam injection.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.

Selected Revisions: May 15, 2018.