• Basic Info
• Top Questions
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What is carbenicillin?
Carbenicillin is an antibiotic in the penicillin group of drugs. It fights bacteria in your body. Carbenicillin is used to treat many different types of infections caused by bacteria, such as bladder infection. Carbenicillin may also be used for purposes other than those listed in this medication guide.

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What are the possible side effects of carbenicillin?

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 any of these serious side effects:

• 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;

• severe skin rash, itching, or peeling;

• agitation, confusion, unusual thoughts or behavior; or

• seizure (black-out or convulsions).

Less serious side effects are more likely to occur, such as:

• nausea, vomiting, stomach pain;

• vaginal itching or discharge;

• headache;

• swollen, black, or "hairy" tongue; or

• thrush (white patches or inside your mouth or throat).

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

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How should I take carbenicillin?
Take this medication exactly as it was prescribed for you. Do not take the medication in larger amounts, or take it for longer than recommended by your doctor. Follow the directions on your prescription label. Take the medicine with a full glass of water. Carbenicillin should be taken on an empty stomach, at least 1 hour before or 2 hours after eating a meal. To be sure this medication is helping your condition, your blood will need to be tested on a regular basis. Your kidney or liver function may also need to be tested. Do not miss any scheduled visits to your doctor.

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What is the most important information I should know about carbenicillin?
Do not use this medication if you are allergic to carbenicillin or to any other penicillin antibiotic, such as amoxicillin (Amoxil), ampicillin (Omnipen, Principen), dicloxacillin (Dycill, Dynapen), oxacillin (Bactocill), penicillin (Beepen-VK, Ledercillin VK, Pen-V, Pen-Vee K, Pfizerpen, V-Cillin K, Veetids), and others. Before using carbenicillin, tell your doctor if you are allergic to cephalosporins such as Ceclor, Ceftin, Duricef, Keflex, and others, or if you have asthma, kidney disease, a bleeding or blood clotting disorder, or a history of any type of allergy.

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What happens if I miss a dose?
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at your next regularly scheduled time. Do not take extra medicine to make up the missed dose.

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What other drugs will affect carbenicillin?
Before taking carbenicillin, tell your doctor if you are using any of the following drugs: methotrexate (Rheumatrex, Trexall); or probenecid (Benemid). If you are using any of these drugs, you may not be able to use carbenicillin, or you may need dosage adjustments or special tests during treatment. There may be other drugs not listed that can affect carbenicillin. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

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Can I take this if I am pregnant or trying to get pregnant or if I am breastfeeding?

Carbenicillin has been assigned to pregnancy category B by the FDA. Animal studies have failed to reveal evidence of fetal harm. There are no controlled data in human pregnancy. There are no literature reports of adverse fetal effects. Carbenicillin should only be given during pregnancy when need has been clearly established.

Carbenicillin class antibiotics are excreted into human milk; however, the amounts are unknown. The manufacturer recommends that caution be used when administering carbenicillin to nursing women.

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Who should NOT use this medication?

• Known hypersensitivity to any penicillin.

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What does my medication look like?
Carbenicillin is available with a prescription under the brand name Geocillin. Other brand or generic formulations may also be available. Ask your pharmacist any questions you have about this medication, especially if it is new to you. Geocillin 382 mg--oblong, yellow, film-coated tablets

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What happens if I overdose?
Seek emergency medical attention if you think you have used too much of this medicine. Symptoms of an carbenicillin overdose may include confusion, behavior changes, a severe skin rash, upset stomach, urinating less than usual, or seizure (black-out or convulsions).

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What should I discuss with my healthcare provider before taking carbenicillin?
Do not use this medication if you are allergic to carbenicillin or to any other penicillin antibiotic, such as: amoxicillin (Amoxil, Amoxicot, Biomox, Dispermox, Trimox); ampicillin (Omnipen, Principen); dicloxacillin (Dycill, Dynapen); oxacillin (Bactocill); or penicillin (Beepen-VK, Ledercillin VK, Pen-V, Pen-Vee K, Pfizerpen, V-Cillin K, Veetids, and others). Before using carbenicillin, tell your doctor if you are allergic to any drugs (especially cephalosporins such as Ceclor, Ceftin, Duricef, Keflex, and others), or if you have:

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Can I stop taking the medication if I feel better?
If you have been diagnosed with a disease for which an antibiotic is needed, you must complete the prescribed course of treatment. Even if you start to feel better, do not skip any doses and remember to take the medication until it is all gone.

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I am on so many medications; do I have to take them all?
This is called polypharmacy—many different medications being used at the same time by one person. Sometimes, being on multiple medications is acceptable and appropriate but at other times it may be problematic. If you are receiving your medications from multiple physicians you need to ensure that they all know what medications you are taking. The best way to do this is to make a list of all the medications you are currently using, including all nutritional supplements, homeopathic remedies, vitamins and over-the-counter drugs (if possible, also include all the diseases you have been diagnosed with). Give a copy to every doctor who takes care of you so they have it on file, this way they can avoid duplicating medications and perhaps even try to consolidate some. After every doctor's visit remember to update the list accordingly. Also, as much as you possibly can, try to use the same pharmacy to fill all your prescriptions, this way any potential drug interactions can be caught and averted.

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Where can I get more information?
More Information

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