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URL of this page: https://medlineplus.gov/druginfo/meds/a693021.html

Ampicillin and Sulbactam Injection

pronounced as (am pi sill' in) (sul bak' tam)

Why is this medication 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.

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. 

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.

Ask your pharmacist or doctor for a copy of the manufacturer’s information for the patient.

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 or pharmacist if you are allergic to this medication, any part of this medication, or any other medications, foods or substances. Tell your doctor or pharmacist about the allergy and what symptoms you had.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take while taking ampicillin and sulbactam injection. 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 medication cause?

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

  • nausea, vomiting, diarrhea
  • 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, itching, hives
  • peeling or blistering of the skin
  • swelling of the eyes, face, mouth, lips, tongue, throat, hands, feet, ankles or lower legs; difficulty breathing or swallowing; wheezing; 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 (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Your healthcare provider will tell you how to store your medication. Store your medication only as directed. Make sure you understand how to store your medication properly.

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reach https://www.upandaway.org

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. 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.

Do not let anyone else take your medication. Your prescription is probably not refillable. If you still have symptoms of infection after you finish the ampicillin and sulbactam injection, call your doctor.

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.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.

Brand names of combination products

  • Unasyn® (containing Ampicillin, Sulbactam)
Last Revised - 04/15/2026