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.