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Ampicillin Injection

Ampicillin Injection 

En Español (Spanish Version)

(am" pi sil' in)

WHY is this medicine prescribed?

Ampicillin injection is used to treat certain infections that are caused by bacteria such as meningitis (infection of the membranes that surround the brain and spinal cord) and lung, blood, heart, urinary tract, and gastrointestinal tract infections. Ampicillin injection is in a class of medications called penicillins. It works by killing bacteria.

Antibiotics such as ampicillin injection will not work for colds, flu, or other viral infections. Taking 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 injection comes as a powder to be mixed with fluid and injected intravenously (into a vein) or intramuscularly (into a muscle). The frequency and length of your treatment depends on the type of infection you have.

You may receive ampicillin injection in a hospital or you may administer the medication at home. If you will be receiving ampicillin injection at home, your healthcare 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 injection. If your symptoms do not improve or get worse, call your doctor.

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

Are there OTHER USES for this medicine?

Ampicillin injection is also used in some pregnant women to prevent passing an infection to the baby during birth. Ampicillin injection is also sometimes used to prevent infection in people who are having certain types of surgery. Talk to your doctor about the risks of using this medication for your condition.

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 injection,

  • tell your doctor and pharmacist if you are allergic to ampicillin; penicillins; cephalosporin antibiotics such as cefaclor, cefadroxil, cefazolin (Ancef, Kefzol), cefdinir, cefditoren (Spectracef), cefepime (Maxipime), cefixime (Suprax), cefotaxime (Claforan), cefotetan, cefoxitin (Mefoxin), cefpodoxime, cefprozil, ceftaroline (Teflaro), ceftazidime (Fortaz, Tazicef, in Avycaz), ceftibuten (Cedax), ceftriaxone (Rocephin), cefuroxime (Zinacef), and cephalexin (Keflex); any other medications; or any of the ingredients in ampicillin 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, Zyloprim); other antibiotics; oral contraceptives; and probenecid (in Col-Probenecid, Probalan). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have mononucleosis (a virus also called 'mono') or have or have ever had allergies, asthma, hives, or hay fever.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while receiving ampicillin 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 injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• nausea

  • diarrhea
  • vomiting

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

• rash

• itching

• hives

  • difficulty breathing or swallowing
  • 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)
  • seizures
  • a return of fever, cough, sore throat, chills, and other signs of infection

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 ( 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.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( for more information if you do not have access to a take-back program.

What should I do in case of OVERDOSE?

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.

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 injection.

If you are diabetic and test your urine for sugar, use Clinistix or TesTape (not Clinitest) to test your urine while using this medication.

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.

Brand Names

  • Omnipen-N®[¶]
  • Penbritin-S®[¶]
  • Polycillin-N®[¶]
  • Totacillin-N®[¶]
  • Also available generically

Other Names

  • Aminobenzylpenicillin

This branded product is no longer on the market. Generic alternatives may be available.

Medication Information

The information contained in this tool is intended as an educational aid only. It is not intended as medical advice for individual conditions or treatment. It is not a substitute for a medical exam, nor does it replace the need for services provided by medical professionals. Talk to your doctor, nurse or pharmacist before taking any prescription or over the counter drugs (including any herbal medicines or supplements) or following any treatment or regimen. Only your doctor, nurse, or pharmacist can provide you with advice on what is safe and effective for you.

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