Nafcillin

Pronunciation: naf-SIL-in
Generic Name: Nafcillin
Brand Name: Generic only. No brands available.

Nafcillin is used for:

Treating and preventing infections caused by certain bacteria.

Nafcillin is a penicillin antibiotic. It works by stopping susceptible bacteria from making cell walls. This results in bacterial death.

Do NOT use Nafcillin if:

• you are allergic to any ingredient in Nafcillin or another penicillin antibiotic (eg, amoxicillin)


• you are taking a tetracycline antibiotic (eg, doxycycline)

Contact your doctor or health care provider right away if any of these apply to you.

Before using Nafcillin:

Some medical conditions may interact with Nafcillin. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

• if you are pregnant, planning to become pregnant, or are breast-feeding


• if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement


• if you have allergies to medicines or other substances


• if you have had a severe allergic reaction (eg, severe rash, hives, breathing difficulties, dizziness) to a cephalosporin antibiotic (eg, cephalexin) or other beta-lactam antibiotic (eg, imipenem)


• if you have asthma

Some MEDICINES MAY INTERACT with Nafcillin. Tell your health care provider if you are taking any other medicines, especially any of the following:

• Tetracyclines (eg, doxycycline) because they may decrease Nafcillin's effectiveness


• Anticoagulants (eg, warfarin), heparin, or methotrexate because their actions and the risk of their side effects may be increased by Nafcillin


• Aminoglycosides (eg, tobramycin), oral contraceptives (birth control pills), or anticoagulants (eg, warfarin) because their effectiveness may be decreased by Nafcillin

This may not be a complete list of all interactions that may occur. Ask your health care provider if Nafcillin may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use Nafcillin:

Use Nafcillin as directed by your doctor. Check the label on the medicine for exact dosing instructions.

• Nafcillin is usually given as an injection at your doctor's office, hospital, or clinic. If you will be using Nafcillin at home, a health care provider will teach you how to use it. Be sure you understand how to use Nafcillin. Follow the procedures you are taught when you use a dose. Contact your health care provider if you have any questions.


• Do not use Nafcillin if it contains particles, is cloudy or discolored, or if the vial is cracked or damaged.


• Keep this product, as well as syringes and needles, out of the reach of children and pets. Do not reuse needles, syringes, or other materials. Ask your health care provider how to dispose of these materials after use. Follow all local rules for disposal.


• To clear up your infection completely, use Nafcillin for the full course of treatment. Keep using it even if you feel better in a few days.


• If you miss a dose of Nafcillin, use it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not use 2 doses at once.

Ask your health care provider any questions you may have about how to use Nafcillin.

Important safety information:

• If your symptoms do not get better within a few days or if they get worse, check with your doctor.


• Some injectable penicillins contain sodium. Contact your doctor for more information if you are on a salt-restricted diet or if your condition could be worsened with an increase in salt intake (eg, congestive heart failure).


• Nafcillin only works against bacteria; it does not treat viral infections (eg, the common cold).


• Be sure to use Nafcillin for the full course of treatment. If you do not, the medicine may not clear up your infection completely. The bacteria could also become less sensitive to this or other medicines. This could make the infection harder to treat in the future.


• Long-term or repeated use of Nafcillin may cause a second infection. Tell your doctor if signs of a second infection occur. Your medicine may need to be changed to treat this.


• Mild diarrhea is common with antibiotic use. However, a more serious form of diarrhea, (pseudomembranous colitis) may rarely occur. This may develop while you use the antibiotic or within several months after you stop using it. Contact your doctor right away if stomach pain or cramps, severe diarrhea, or bloody stools occur. Do not treat diarrhea without first checking with your doctor.


• Hormonal birth control (eg, birth control pills) may not work as well while you are using Nafcillin. To prevent pregnancy, use an extra form of birth control (eg, condoms).


• Lab tests, including white blood cell counts, liver or kidney function, or blood tests, may be performed while you use Nafcillin. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.


• Use Nafcillin with caution in the ELDERLY; they may be at higher risk of developing blood clots.


• Use Nafcillin with extreme caution in CHILDREN and NEWBORNS who have diarrhea or an infection of the stomach or bowel.


• PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Nafcillin while you are pregnant. Nafcillin is found in breast milk. If you are or will be breast-feeding while you use Nafcillin, check with your doctor. Discuss any possible risks to your baby.

Possible side effects of Nafcillin:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Mild diarrhea; nausea; pain at the injection site; vomiting.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); bloody stools; chills; fever; muscle pain; pain, redness, or swelling at the injection site; severe diarrhea; stomach pain or cramps ; vaginal irritation or discharge.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

See also: Nafcillin side effects (in more detail)

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include agitation; confusion; hallucinations; jerking movements; seizures; stupor.

Proper storage of Nafcillin:

Nafcillin is usually handled and stored by a health care provider. If you are using Nafcillin at home, store Nafcillin as directed by your pharmacist or health care provider. Keep Nafcillin out of the reach of children and away from pets.

General information:

• If you have any questions about Nafcillin, please talk with your doctor, pharmacist, or other health care provider.


• Nafcillin is to be used only by the patient for whom it is prescribed. Do not share it with other people.


• If your symptoms do not improve or if they become worse, check with your doctor.


• Check with your pharmacist about how to dispose of unused medicine.

This information is a summary only. It does not contain all information about Nafcillin. If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.

Issue Date: February 1, 2012

Database Edition 12.1.1.002

Copyright © 2012 Wolters Kluwer Health, Inc.

More Nafcillin resources

• Nafcillin Side Effects (in more detail)
• Nafcillin Use in Pregnancy & Breastfeeding
• Nafcillin Drug Interactions
• Nafcillin Support Group
• 1 Review for Nafcillin - Add your own review/rating

• Nafcillin Prescribing Information (FDA)


• nafcillin injection Concise Consumer Information (Cerner Multum)


• Nafcillin Sodium Monograph (AHFS DI)

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