Do NOT use Vantin if:

• you are allergic to any ingredient in Vantin or to any other cephalosporin antibiotic (eg, cephalexin, cefprozil).

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

Tell your health care provider 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, foods, or other substances
• if you have diarrhea, a stomach or intestinal infection, or a blood clotting problem
• if you have had a severe allergic reaction (eg, severe rash, hives, difficulty breathing, dizziness) to a penicillin antibiotic (eg, amoxicillin) or other beta-lactam antibiotic (eg, imipenem).

Some medicines may interact with Vantin. Tell your health care provider if you are taking any other medicines, especially any of the following:

• Aminoglycosides (eg, gentamicin), cyclosporine, or diuretics (eg, furosemide, hydrochlorothiazide) because the risk of side effects on the kidney may be increased.

This may not be a complete list of all interactions that may occur. Ask your health care provider if Vantin 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.

Important safety information:

• 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.
• Vantin only works against bacteria; it does not treat viral infections (eg, the common cold).
• Be sure to use Vantin 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 Vantin 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.
• Lab tests, including liver function, kidney function, and complete blood cell counts, may be performed while you use Vantin. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
• Pregnancy and breast-feeding: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Vantin while you are pregnant. The medicine is found in breast milk. Do not breastfeed while taking Vantin.

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:

Diarrhea; headache; loose stools; nausea; upset stomach; 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; seizures; severe diarrhea; skin rash; stomach pain/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.