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Drugs & Medications

Lanacillin VK

GENERIC NAME(S): PENICILLIN V POTASSIUM

Uses

Penicillin is an antibiotic used to treat and prevent a wide variety of bacterial infections. It works by stopping the growth of bacteria.

This antibiotic treats and prevents only bacterial infections. It will not work for virus infections (such as the common cold, flu). Unnecessary use or overuse of any antibiotic can lead to its decreased effectiveness.

How to use Lanacillin VK

Take this medication by mouth as directed by your doctor. This medication may be taken with or without food. However, penicillin is best absorbed when taken on an empty stomach (1 hour before or 2 hours after meals).

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

Antibiotics work best when the amount of medicine in your body is kept at a constant level. Therefore, take this drug at evenly spaced intervals.

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 allow bacteria to continue to grow, which may result in a return of the infection.

Tell your doctor if your condition persists or worsens.

Side Effects

Upset stomach, nausea, vomiting, diarrhea, and mouth sores may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

Although this effect is uncommon, you may develop a black, "hairy" tongue while taking this medication. This effect is harmless and usually goes away after treatment. Maintain good oral hygiene, and brush your tongue with a soft toothbrush twice a day. Consult your doctor or pharmacist for more information.

Remember that your doctor has prescribed this medication because he or she 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 immediately if any of these unlikely but serious side effects occur: unusual tiredness, joint/muscle pain.

Tell your doctor immediately if any of these rare but very serious side effects occur: easy bruising/bleeding.

This medication may rarely cause a severe intestinal condition (Clostridium difficile-associated diarrhea) due to a type of resistant bacteria. This condition may occur during treatment or weeks to months after treatment has stopped. Do not use anti-diarrhea products or narcotic pain medications if you have any of the following symptoms because these products may make them worse. Tell your doctor immediately if you develop: persistent diarrhea, abdominal or stomach pain/cramping, blood/mucus in your stool.

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, seek immediate medical attention if you notice any of the following symptoms of a serious allergic reaction: rash, itching/swelling (especially of the face/tongue/throat), new fever, severe dizziness, trouble breathing.

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.

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 penicillin, tell your doctor or pharmacist if you are allergic to it; or to other antibiotics including penicillin-type medications (such as amoxicillin, ampicillin) or cephalosporins (such as cephalexin, cefuroxime); 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 problems.

Kidney function declines as you grow older. This medication is removed by the kidneys. Therefore, older adults may be more sensitive to this drug.

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

This drug passes into breast milk. Consult your doctor before breast-feeding.

Interactions

Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor or pharmacist first.

Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: vaccines that contain live bacteria, methotrexate, tetracyclines, khat, guar gum.

Before taking penicillin, tell your doctor or pharmacist if you are also taking probenecid. Probenecid slows down the removal of penicillin from your body, resulting in higher levels of this antibiotic in your bloodstream. For certain types of difficult-to-treat infections, your doctor may prescribe these 2 medications together in order to achieve this effect. Consult your doctor or pharmacist for more details.

Although most antibiotics probably do not affect hormonal birth control such as pills, patch, or ring, some antibiotics may decrease their effectiveness. This could cause pregnancy. Examples include rifamycins such as rifampin or rifabutin. Be sure to ask your doctor or pharmacist if you should use additional reliable birth control methods while using this antibiotic.

Penicillin may cause false positive results with certain diabetic urine testing products (cupric sulfate-type). This drug may also affect the results of certain lab tests. Make sure laboratory personnel and your doctors know you use this drug.

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

Overdose

If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe vomiting, persistent diarrhea.

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 told to do so by your doctor. A different medication may be necessary in that case.

With prolonged treatment, laboratory and/or medical tests (such as kidney function, complete blood counts) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.

Missed Dose

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

Storage

Store at room temperature between 59-86 degrees F (15-30 degrees C) away from light and moisture. Do not store in the bathroom. Keep all medicines 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 for more details about how to safely discard your product.

Information last revised March 2013. Copyright(c) 2013 First Databank, Inc.

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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, expect as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

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