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Penicillin

What is Penicillin

Penicillin is an antibiotic in the class of drugs called penicillins. It fights bacteria in your body.

Penicillin is used to treat many different types of infections, such as tonsillitis, pneumonia, strep throat, bronchitis, and infections of the skin.

Penicillin may also be used for purposes other than those listed in this medication guide.

General medical information about Penicillin

Take all of the Penicillin that has been prescribed for you even if you begin to feel better. Your symptoms may begin to improve before the infection is completely treated.

Penicillin may decrease the effectiveness of birth control pills. Use a second method of birth control while taking Penicillin to protect against pregnancy.

Who should not take Penicillin

If you have ever had an allergic reaction to another penicillin or to a cephalosporin, do not take Penicillin unless your doctor is aware of your allergy and monitors your therapy.

Before taking this medication, tell your doctor if you have kidney disease, stomach or intestinal disease, or infectious mononucleosis. You may not be able to take Penicillin because of an increased risk of side effects.

If you are a diabetic, some glucose urine tests may give false positive results while you are taking Penicillin.

Penicillin is in the FDA pregnancy category B. This means that it is unlikely to harm an unborn baby. Do not, however, take Penicillin without first talking to your doctor if you are pregnant.

It is not known whether Penicillin passes into breast milk. Do not take this medication without first talking to your doctor if you are breast-feeding a baby.

How should take Penicillin

Take Penicillin exactly as directed by your doctor. If you do not understand these instructions, ask your pharmacist, nurse, or doctor to explain them to you.

Take each dose with a full glass of water.

Penicillin can be taken with or without food. Do not drink fruit juice or carbonated beverages (soda) with your dose, however. These beverages will decrease the effectiveness of the drug.

Penicillin should be taken at evenly spaced intervals throughout the day and night to keep the level in your blood high enough to treat the infection.

Shake the liquid form of Penicillin well before measuring a dose. To ensure that you get a correct dose, measure the suspension with a dose-measuring spoon or cup, not a regular tablespoon. If you do not have a dose-measuring device, ask your pharmacist where you can get one.

Take all of the Penicillin that has been prescribed for you even if you begin to feel better. Your symptoms may start to improve before the infection is completely treated.

Store the tablets and capsules at room temperature and store the suspension in the refrigerator for longer use. The suspension is good for 14 days if it is stored in the refrigerator. Throw away any unused liquid after this amount of time.

If you miss a dose:

Take the missed dose as soon as you remember. However, if it is almost time for your next dose, skip the dose you missed and take only your next regularly scheduled dose. Do not take a double dose of this medication unless otherwise directed by your doctor.

If you have only missed one dose, you can take the rest of your scheduled doses for the day at evenly spaced intervals.

What happens if you overdose:

Seek emergency medical attention.

Symptoms of an Penicillin overdose include muscle spasms or weakness, pain or twitching, pain in the fingers or toes, loss of feeling in the fingers or toes, seizures, confusion, coma, and agitation.

Avoid while taking Penicillin

Alcohol may irritate your stomach if taken with Penicillin, so use it with moderation.

Possible side effects of Penicillin

If you experience any of the following serious side effects, stop taking Penicillin and seek emergency medical attention:
- an allergic reaction (shortness of breath; closing of your throat; hives; swelling of your lips, face, or tongue; rash; or fainting);
- seizures;
- severe watery diarrhea and abdominal cramps; or
- unusual bleeding or bruising.

Other, less serious side effects may be more likely to occur. Continue to take Penicillin and talk to your doctor if you experience
- mild nausea, vomiting, diarrhea, or abdominal pain;
- white patches on the tongue (thrush/yeast infection);
- itching or discharge of the vagina (vaginal yeast infection); or
- black, "hairy" tongue or sore mouth or tongue.

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.

What other drugs will affect Penicillin

Some drugs may decrease the effects of Penicillin and prevent it from properly treating your infection. Before taking Penicillin, tell your doctor if you are taking any of the following drugs:
- cholestyramine (Questran) or colestipol (Colestid); or
- another antibiotic (for the same or for a different infection) such as erythromycin (Ery-Tab, E-Mycin, E.E.S., others), tetracycline (Sumycin, others), minocycline (Minocin), doxycycline (Doryx, Vibramycin, others), or any other.

Penicillin may decrease the effectiveness of birth control pills. Use a second method of birth control while taking Penicillin to protect against pregnancy.

Penicillin increases the effects of methotrexate, and you may need a dose adjustment during therapy with Penicillin.

Penicillin also increases the side effects of allopurinol (Zyloprim) and may cause a rash.

Probenecid (Benemid) increases the effects of Penicillin. These drugs may be used together for this purpose; however, be sure your doctor is aware if you are taking probenecid. You may need a lower dose of penicillin.

Drugs other than those listed here may also interact with Penicillin. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines.

All prescription drugs:

A
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B
baclofen
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C
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G
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H
herceptin humalog humira hydroxyzine hyzaar  
I
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K
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L
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M
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N
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O
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P
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S
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T
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V
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X
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Y
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