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Ampicillin - Oral

Pronunciation: AM-pi-SIL-in

Common Brand Name(s): Penbritin

Important: How To Use This Information

This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.

Uses

Ampicillin is used to treat a wide variety of bacterial infections. It is a penicillin-type antibiotic. It works by stopping the growth of bacteria.

This antibiotic treats only bacterial infections. It will not work for viral infections (such as common cold, flu). Using any antibiotic when it is not needed can cause it to not work for future infections.

How To Use

Take this medication by mouth as directed by your doctor, usually 4 times a day (every 6 hours). Take ampicillin on an empty stomach (1 hour before or 2 hours after a meal) with a full glass of water. Drink plenty of fluids while using this medication unless your doctor tells you otherwise.

The dosage is based on your medical condition and response to therapy.

For the best effect, take this antibiotic at evenly spaced times. To help you remember, take this medication at the same time(s) every day.

Continue to take this medication until the full prescribed amount is finished even if symptoms disappear after a few days. Stopping the medication too early may result in a return of the infection.

Tell your doctor if your condition lasts or gets worse.

Side Effects

Nausea, vomiting, diarrhea, or mouth/tongue sores may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including:

  • nausea or vomiting that doesn't stop
  • sore throat or fever that doesn't go away
  • dark urine
  • stomach/abdominal pain
  • yellowing eyes or skin
  • easy bruising or bleeding

This medication may rarely cause a severe intestinal condition due to a bacteria called C. difficile. This condition may occur during treatment or weeks to months after treatment has stopped. Tell your doctor right away if you develop:

  • diarrhea that doesn't stop
  • abdominal or stomach pain/cramping
  • blood/mucus in your stool

If you have these symptoms, do not use anti-diarrhea or opioid products because they may make symptoms worse.

Use of this medication for prolonged or repeated periods may result in oral thrush or a new vaginal yeast infection (oral or vaginal fungal infection). Contact your doctor if you notice white patches in your mouth, a change in vaginal discharge or other new symptoms.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

  • rash
  • itching/swelling (especially of the face/tongue/throat)
  • severe dizziness
  • trouble breathing

Ampicillin can commonly cause a mild rash that is usually not serious. However, you may not be able to tell it apart from a rare rash that could be a sign of a severe allergic reaction. Get medical help right away if you develop any rash.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

Before taking ampicillin, tell your doctor or pharmacist if you are allergic to it; or to penicillin or cephalosporin antibiotics; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

  • kidney disease
  • a certain type of viral infection (infectious mononucleosis)

Ampicillin may cause live bacterial vaccines (such as typhoid vaccine) to not work well. Tell your health care professional that you are using ampicillin before having any immunizations/vaccinations.

Older adults may be at greater risk for side effects while using this drug.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

Ampicillin passes into breast milk. Consult your doctor before breast-feeding.

Drug Interactions

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug include:

  • methotrexate
  • tetracyclines

This medication may interfere with certain lab tests (such as certain diabetic urine tests), possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug.

Overdose

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Alberta residents can call PADIS (Poison and Drug Information Service) 24 hours a day at 1-800-332-1414. Canada residents can call a provincial poison control center. Symptoms of overdose may include: diarrhea that doesn't stop, severe vomiting, unusual change in the amount of urine, or seizures.

Notes

Do not share this medication with others.

This medication has been prescribed for your current condition only. Do not use it later for another infection unless your doctor tells you to.

If you are using this drug for a long time, lab and/or medical tests (such as kidney/liver function, complete blood count) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.

Missed Dose

If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Use your next dose at the regular time. Do not double the dose to catch up.

If you have questions about missing a dose or you don't have more medication, contact your healthcare provider or pharmacist.

Storage

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

This information does not replace the advice of a doctor. Healthwise, Incorporated, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content.