Penbritin

Brand Name:Penbritin, Novo-Ampicillin, Nu-Ampi, Apo-Ampi

Prescription needed: Yes

What is this drug used for?

Ampicillin is an antibiotic used to treat various bacterial infections such as pneumonia, meningitis, urinary and gastrointestinal tract infections and infections of the blood.

Is there any reason not to take this drug?

Do not take this medication if you are allergic to ampicillin, or if you have ever had a serious allergic reaction to other beta lactam antibiotics such as penicillin, amoxicillin, cloxacillin or any of the group of drugs called cephalosporins.

Always disclose your full medical history with the medical team that is taking care of you, in order for them to provide you with the safest and most effective care. Inform your doctor if you have any kidney problems as your dose of ampicillin may need adjustment.

What about possible side effects?

This medication is usually well tolerated but you should be aware of some potential side effects. The following side effects are more common and can be quite bothersome, but unless they are severe, you should continue taking ampicillin as prescribed. Contact your doctor or pharmacist to get advice on how to manage these side effects for the course of treatment.

  • diarrhea
  • upset stomach and stomach cramps
  • nausea and/or vomiting
  • minor skin rash

Antibiotics may make you prone to oral thrush infections and vaginal yeast infections. Contact your doctor or pharmacist regarding treatments.

If you have a condition called infectious mononucleosis, you are at higher risk of experiencing a skin rash related to ampicillin.

Call your doctor immediately if you experience any of the following more serious side effects:

  • difficulty breathing or swallowing
  • severe dizziness
  • severe headache
  • hives all over the body or near the face and throat
  • itching all over the body
  • seizures
  • severe skin rash
  • swelling of the lips, face or tongue
  • unusual bleeding or bruising
  • wheezing
  • blood in the stool
This is not a complete list of side effects. If you are concerned about these or other unusual symptoms while taking this medication, ask your doctor and/or pharmacist for more information and advice.

What if I am taking other drugs?

Always provide your doctor with a list of all other drugs you are taking (including over-the-counter medications and herbal/natural products) as they may interact with and/or may change the safety or effectiveness of either drug. Tell your doctor specifically if you are taking any of the following drugs:

  • allopurinol – may make you more prone to getting skin rashes related to use of ampicillin
  • atenolol – ampicillin may reduce how well atenolol controls blood pressure and angina
  • birth control pills – there have been case reports suggesting antibiotics may decrease how well your birth control pills work to prevent pregnancy. While this interaction is unlikely, for peace of mind, consider using an additional method of birth control (i.e. condom) for the rest of that cycle
  • warfarin – may result in excessive blood thinning effects. Consult with your doctor about additional blood testing when starting ampicillin and when finishing
  • tetracycline antibiotics e.g. Minocycline, doxycycline, tetracycline – decreased effect of ampicillin
  • probenecid – increased chances of side effects from ampicillin
  • methotrexate – ampicillin may increase risks of side effects from methotrexate
  • typhoid vaccine e.g. Vivotif – wait at least 24 hours after stopping ampicillin to vaccinate with the oral typhoid vaccine
This is not a complete list of drug interactions. Ask your doctor or pharmacist to review your own list of medications.

Other information:

If you have diabetes and regularly check your urine for sugar using Clinitest tablets, ampicillin may contribute to incorrect results. 

Children: Safely used in appropriate doses.

Seniors: Safely used in appropriate doses.

Pregnant women: Safe for use in pregnancy

Women who are nursing: Ampicillin passes into breast milk in low concentrations and is considered safe for use in nursing women. Your infant may experience diarrhea or mild skin rash. Just like adults have the risk of an allergic reaction, there is also the risk of an allergic reaction in your infant.  

People who drive or operate machinery: Safely used.

Alcohol: No specific problems with alcohol consumption. Always drink in moderation.

Overdose: Symptoms of overdose include hallucinations, seizures, and confusion. If an overdose is suspected, seek emergency medical help right away.

Stopping the drug: In order to clear up your infection completely, you must take ampicillin for the entire prescribed course of treatment even if you feel better.

If you miss a dose: Take any missed dose as soon as possible, then continue as prescribed on your medication bottle. Taking ampicillin around the clock as prescribed will ensure optimal effect. Do not take a double dose.

Storage: Store ampicillin as directed on the packaging. Closed container; cool, dry location away from excess moisture (not in the bathroom) always out of reach of children.

Dietary precautions: Food decreases the amount of ampicillin your body can absorb if taken at the same time. Ampicillin should be taken on an empty stomach, either 1 hour before a meal or 2 hours after a meal.

Some of the stomach-related side effects may be minimized if you add some yoghurt or buttermilk to your diet while on a course of ampicillin. Remember to separate from ampicillin as directed above.