This medication may rarely cause tendon damage (e.g., tendinitis, tendon rupture) during or after treatment. Your risk for tendon problems is greater if you are over 60 years of age, if you are taking corticosteroids (such as prednisone), or if you have had a kidney, heart or lung transplant. Stop exercising, rest, and seek immediate medical attention if you develop joint/muscle/tendon pain or swelling.Who should not take norfloxacin?
Read the Medication Guide provided by your pharmacist before you start taking norfloxacin and each time you get a refill. If you have any questions, consult your doctor or pharmacist.
Take this medication by mouth, usually twice a day, at least 1 hour before or 2 hours after a meal or dairy products (e.g., milk, yogurt). Take with a full glass of water (8 ounces or 240 milliliters). The dosage is based on your medical condition and response to treatment. Drink plenty of fluids while taking this medication unless your doctor tells you otherwise.
Take this medication at least 2 hours before or 2 hours after taking any drugs that contain magnesium, aluminum, or calcium. Some examples include quinapril, certain forms of didanosine (chewable/dispersible buffered tablets or pediatric oral solution), vitamins/minerals, and antacids. Follow the same instructions if you take calcium-enriched juice, bismuth subsalicylate, sucralfate, iron, and zinc. These medications/products bind with norfloxacin and prevent its full absorption.
Antibiotics work best when the amount of medicine in your body is kept at a constant level. It is important not to miss a dose. To help you remember, take this medication at the same times every day.
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.
See also Warning section.
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: sunburn (sun sensitivity).
Tell your doctor immediately if any of these rare but very serious side effects occur: unusual bruising/bleeding, signs of a new infection (e.g., new/persistent fever, persistent sore throat), unusual change in the amount of urine, signs of liver problems (e.g., unusual tiredness, stomach/abdominal pain, persistent nausea/vomiting, yellowing eyes/skin, dark urine).
Seek immediate medical attention if any of these rare but very serious side effects occur: severe/persistent headache, vision changes, shaking (tremors), seizures, severe dizziness, fainting, fast/irregular heartbeat, mental/mood changes (e.g., anxiety, confusion, hallucinations, depression, rare thoughts of suicide).
Rarely, this medication may cause serious, possibly permanent, nerve problems (peripheral neuropathy). Stop taking norfloxacin and tell your doctor right away if you have any of the following symptoms: pain/numbness/burning/tingling/weakness in your arms, hands, legs, or feet, changes in how you sense touch/pain/temperature/vibration/body position.
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. 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), 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.
Before taking norfloxacin, tell your doctor or pharmacist if you are allergic to it; or to other quinolone antibiotics such as ciprofloxacin, gemifloxacin, levofloxacin, moxifloxacin, or ofloxacin; 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: certain metabolic disorder (G6PD deficiency), diabetes, heart problems (e.g., recent heart attack), joint/tendon problems (e.g., tendonitis, bursitis), kidney disease, myasthenia gravis, nerve problems (such as peripheral neuropathy), seizure disorder, conditions that increase your risk of seizures (e.g., brain/head injury, brain tumors, cerebral atherosclerosis).
Norfloxacin may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can infrequently result in serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away.
The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using norfloxacin, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions: certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG), family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death).
Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/"water pills") or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using norfloxacin safely.
This medication may rarely cause serious changes in blood sugar levels, especially if you have diabetes. Watch for symptoms of high blood sugar including increased thirst and urination. Also watch for symptoms of low blood sugar such as nervousness, shakiness, fast heartbeat, sweating, or hunger. Check your blood sugar regularly as directed by your doctor and report any changes. If you experience symptoms of low blood sugar, you may raise your blood sugar by using glucose tablets/gel or eating a quick source of sugar such as table sugar, honey, or candy, or drinking fruit juice or non-diet soda. Tell your doctor immediately about the reaction and the use of this product. To help prevent low blood sugar, eat meals on a regular schedule, and do not skip meals. Your doctor may need to switch you to another antibiotic or adjust your diabetes medications if any reaction occurs.
This drug may make you dizzy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.
This medication may make you more sensitive to the sun. Avoid prolonged sun exposure, tanning booths, and sunlamps. Use a sunscreen and wear protective clothing when outdoors.
Caution is advised when using this medication in children younger than 18 years because they may be at greater risk for joint/tendon problems. Discuss the risks and benefits with the doctor.
Older adults may be more sensitive to the side effects of this drug (such as blood sugar or tendon problems), especially if they are also taking corticosteroids (e.g., prednisone, hydrocortisone). They may also be more sensitive to QT prolongation (see above).
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
It is unknown if this drug passes into breast milk. However, similar drugs pass into breast milk. Consult your doctor before breast-feeding.
See also the How to Use section.
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 them first.
This drug should not be used with the following medication because very serious interactions may occur: strontium.
If you are currently using the medication listed above, tell your doctor or pharmacist before starting norfloxacin.
Many drugs besides norfloxacin may affect the heart rhythm (QT prolongation), including amiodarone, dofetilide, procainamide, quinidine, sotalol, certain macrolide antibiotics (e.g., erythromycin, clarithromycin), and certain antipsychotic medications (e.g., pimozide, thioridazine, ziprasidone), among others. Therefore, before using norfloxacin, report all medications you are currently using to your doctor or pharmacist.
Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: live bacterial vaccines (e.g., typhoid, BCG), "blood thinners" (e.g., warfarin), corticosteroids (e.g., prednisone, hydrocortisone), drugs removed from your body by certain liver enzymes (such as clozapine, duloxetine, ropinirole, tacrine, tizanidine), nonsteroidal anti-inflammatory drugs (NSAIDs such as ibuprofen, naproxen), urinary alkalinizers (e.g., potassium/sodium citrate).
Also report the use of drugs that might increase seizure risk when combined with this medication such as isoniazid (INH), phenothiazines (e.g., chlorpromazine), theophylline, or tricyclic antidepressants (e.g., amitriptyline), among others. Consult your doctor or pharmacist for details.
Avoid drinking large amounts of beverages containing caffeine (coffee, tea, colas), eating large amounts of chocolate, or taking over-the-counter products that contain caffeine. This drug may increase and/or prolong the effects of caffeine.
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.
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.
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.
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.
Laboratory and/or medical tests (e.g., kidney function, complete blood count, blood glucose) may be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.
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.
Store at room temperature at 77 degrees F (25 degrees C) away from light and moisture. Brief storage between 59-86 degrees F (15-30 degrees C) is permitted. 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 January 2015. Copyright(c) 2015 First Databank, Inc.
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