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(ampicillin) Capsules, USP 250mg and 500mg
Principen for Oral Suspension
(ampicillin) for Oral Suspension, USP 125mg/5ml and 250mg/5ml
- Patient Information:
Details with Side Effects
Ampicillin trihydrate is a semisynthetic penicillin derived from the basic penicillin nucleus, 6-aminopenicillanic acid. Ampicillin is designated chemically as (2S, 5R, 6R)-6-[(8)-2-Amino-2-phenylacetamido]-3,3-dimethyl-t-oxo-4-thia-1- azabicyclo[3.2.0] heptane-2-carboxylic acid. The chemical formula is C16H19N3O4S·3H2O and its molecular weight is 403.45.
This is the anhydrous form of ampicillin. It is prepared as the trihydrate form attached to 3 water (H2O) molecules.
What are the possible side effects of ampicillin (Principen)?
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have a serious side effect such as:
- fever, sore throat, and headache with a severe blistering, peeling, and red skin rash;
- diarrhea that is watery or bloody;
- fever, chills, body aches, flu symptoms;
- easy bruising or bleeding, unusual weakness;
- urinating less than usual or not at all;
- agitation, confusion, unusual thoughts or behavior;...
What are the precautions when taking ampicillin (Principen)?
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).
Kidney function declines as you grow older. This medication is removed by the kidneys. Therefore, elderly people may be more sensitive to this drug.
This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor.
Last reviewed on RxList: 1/29/2005
This monograph has been modified to include the generic and brand name in many instances.
Additional Principen Information
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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