Health Library

Norfloxacin (By mouth)

Norfloxacin (nor-FLOX-a-sin)

Treats infections. This medicine is a quinolone antibiotic.

Brand Name(s):

When This Medicine Should Not Be Used:

How to Use This Medicine:

Tablet

• Your doctor will tell you how much medicine to use. Do not use more than directed. Take this medicine at the same time each day.
• Take this medicine at least 1 hour before or 2 hours after you eat a meal or use dairy products such as milk, cheese, cream, or yogurt. Take the medicine only with water. Do not take it with milk or with any juice that has calcium added to it.
• Drink extra fluids so you will urinate more often and help prevent kidney problems.
• Take all of the medicine in your prescription to clear up your infection, even if you feel better after the first few doses.
• This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
• Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
• Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Some foods and medicines can affect how norfloxacin works. Tell your doctor if you are using any of the following:
  • Cisapride, clozapine, cyclosporine, erythromycin, nitrofurantoin, probenecid, ropinirole, tacrine, theophylline, tizanidine
  • Blood thinner (including warfarin)
  • Diabetes medicine (including glyburide)
  • Medicine for depression or mental illness
  • Medicine for heart rhythm problems (including amiodarone, procainamide, quinidine, sotalol)
  • NSAID pain medicine (including aspirin, celecoxib, diclofenac, ibuprofen, naproxen)
  • Steroid medicine (including hydrocortisone, methylprednisolone, prednisone)
• Take norfloxacin at least 2 hours before or 2 hours after you take antacids containing aluminum or magnesium, zinc, iron, sucralfate, or didanosine. This includes vitamin/mineral supplements.
• This medicine slows the digestion of caffeine, so it might affect you for longer than normal.

Warnings While Using This Medicine:

• Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, diabetes, heart disease, myasthenia gravis, G6PD deficiency, or a history of heart rhythm problems (such as QT prolongation) or seizures. Tell your doctor if you have ever had tendon or joint problems, including rheumatoid arthritis, or if you have received a transplant.
• This medicine may cause the following problems:
  • Tendinitis or tendon rupture (may happen after treatment ends)
  • Nerve damage in the arms or legs
  • Liver damage
  • Heart rhythm changes
• This medicine may make you dizzy or lightheaded. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.
• This medicine can cause diarrhea. Call your doctor if the diarrhea becomes severe, does not stop, or is bloody. Do not take any medicine to stop diarrhea until you have talked to your doctor. Diarrhea can occur 2 months or more after you stop taking this medicine.
• This medicine may make your skin more sensitive to sunlight. Wear sunscreen. Do not use sunlamps or tanning beds.
• Call your doctor if your symptoms do not improve or if they get worse.
• Keep all medicine out of the reach of children. Never share your medicine with anyone.

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
• Blistering, peeling, red skin rash
• Change in how much or how often you urinate
• Dark urine or pale stools, nausea, vomiting, loss of appetite, stomach pain, yellow skin or eyes
• Diarrhea that may contain blood
• Fast, slow, or uneven heartbeat
• Numbness, tingling, weakness, or burning pain in your hands, arms, legs, or feet
• Pain, stiffness, swelling, or bruises around your ankle, leg, shoulder, or other joint
• Seizures, severe headache, unusual thoughts or behaviors, trouble sleeping, feeling anxious, confused, or depressed, seeing, hearing, or feeling things that are not there
• Unusual bleeding, bruising, or weakness

If you notice these less serious side effects, talk with your doctor:

• Mild diarrhea or nausea

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 9/6/2024