Treats infections caused by bacteria. This medicine belongs to a class of drugs called penicillins.
There may be other brand names for this medicine.
When This Medicine Should Not Be Used
You should not use this medicine if you have had an allergic reaction to nafcillin or other types of penicillin. Some forms of this medicine contain dextrose and should not be used if you are allergic to corn or corn products.
How to Use This Medicine
- Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine is given through a needle placed in one of your veins.
- A nurse or other trained health professional will give you this medicine.
- Keep using this medicine for the full treatment time, even if you feel better after the first few doses. Your infection may not clear up if you stop using the medicine too soon.
If a dose is missed:
- This medicine needs to be given on a fixed schedule. If you miss a dose or forget to use your medicine, call your doctor or pharmacist for instructions.
How to Store and Dispose of This Medicine
- If you store this medicine at home, keep it in the refrigerator. Do not freeze.
- Keep all medicine away from children and never share your medicine with anyone.
- Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any leftover medicine, containers, and other supplies. You will also need to throw away old medicine after the expiration date has passed.
Drugs and Foods to Avoid
Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
- Make sure your doctor knows if you are also using tetracycline antibiotics (such as doxycycline, minocycline, Minocin®, or Sumycin®), cyclosporine (Sandimmune®, Neoral®), or a blood thinner such as warfarin (Coumadin®).
Warnings While Using This Medicine
- Make sure your doctor knows if you are pregnant or breastfeeding, or if you have asthma, liver disease, or kidney disease.
- Make sure your doctor knows if you are allergic to cephalosporin antibiotics, such as cefaclor, cefadroxil, cephalexin, or Ceclor®.
- If you have severe diarrhea, ask your doctor before taking any medicine to stop the diarrhea.
- Your doctor will need to check your blood or urine at regular visits while you are using this medicine. Be sure to keep all appointments.
- If your symptoms do not improve or if they get worse, call your doctor.
Possible Side Effects While Using This Medicine
Call your doctor right away if you notice any of these side effects:
- Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
- Black or hairy tongue.
- Decrease in how much or how often you urinate.
- Fever, chills, cough, sore throat, and body aches.
- Lightheadedness or fainting.
- Pain, itching, burning, swelling, or a lump under your skin where the needle is placed.
- Red or dark brown urine.
- Severe diarrhea, especially if it is bloody, or severe stomach cramps or pain.
- Sores or white patches on your lips, mouth, or throat.
- Unusual bleeding or bruising.
- Unusual weakness or tiredness.
If you notice these less serious side effects, talk with your doctor:
- Mild diarrhea, nausea, or vomiting.
- Muscle or joint pain.
- Skin rash.