Drug Interactions between Copper and norfloxacin

Taking norfloxacin with food or products that contain minerals like calcium, iron, magnesium and zinc can interfere with its absorption and reduce its levels in the blood and urinary tract. This may make the medication less effective in treating your infection. You should take norfloxacin on an empty stomach at least one hour before or two hours after eating a meal or consuming milk or other dairy products. Do not use mineral supplements, multivitamins, antacids, or other products that may contain calcium, iron, magnesium or zinc within the two-hour period before or after taking norfloxacin. Talk to your doctor or pharmacist if you have questions on how to take this or other medications you are prescribed. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medication without first talking to your doctor.

In general, multivitamin with minerals and norfloxacin should not be taken orally at the same time. Products that contain aluminum, calcium, iron, magnesium, zinc and/or other minerals may interfere with the absorption of norfloxacin into the bloodstream and reduce its effectiveness in treating your infection. If possible, it may be best to avoid taking multivitamin with minerals while you are being treated with norfloxacin. Otherwise, you should separate their dosing times by as much as possible, usually at least 2 to 4 hours. Talk to your healthcare provider if you are unsure whether your medications contain something that could potentially interact or if you have questions on how to take this or other medications you are prescribed. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Using caffeine together with norfloxacin may increase the effects of caffeine. Contact your doctor if you experience headache, tremor, restlessness, nervousness, insomnia, and increased blood pressure or heart rate. If your doctor does prescribe these medications together, you may need a dose adjustment or special test to safely use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Quinolones have been reported to prolong the QT interval of the electrocardiogram in some patients. QT prolongation may potentiate the risk of ventricular arrhythmias including ventricular tachycardia, ventricular fibrillation, and torsade de pointes. The risk appears to be greatest with grepafloxacin and sparfloxacin (both are no longer marketed in the U.S.), although cardiovascular morbidity and mortality attributable to QT prolongation have also been reported rarely with others like gatifloxacin, levofloxacin, ciprofloxacin, and ofloxacin. Reported cases have primarily occurred in patients with advanced age, cardiac disease, electrolyte disturbances, and/or underlying medical problems for which they were receiving concomitant medications known to prolong the QT interval. Therapy with quinolones should be avoided in patients with known QT prolongation and/or uncorrected electrolyte disorders (hypokalemia or hypomagnesemia) and in patients treated concomitantly with class IA or III antiarrhythmic agents. Cautious use with ECG monitoring is advised in patients with other proarrhythmic conditions such as clinically significant bradycardia, congestive heart failure, acute myocardial ischemia, and atrial fibrillation. As QT prolongation may be a concentration-dependent effect, it is important that the recommended dosages or infusion rates of these drugs not be exceeded, particularly in patients with renal and/or hepatic impairment.

Quinolones have been reported to prolong the QT interval of the electrocardiogram in some patients. QT prolongation may potentiate the risk of ventricular arrhythmias including ventricular tachycardia, ventricular fibrillation, and torsade de pointes. The risk appears to be greatest with grepafloxacin and sparfloxacin (both are no longer marketed in the U.S.), although cardiovascular morbidity and mortality attributable to QT prolongation have also been reported rarely with others like gatifloxacin, levofloxacin, ciprofloxacin, and ofloxacin. Reported cases have primarily occurred in patients with advanced age, cardiac disease, electrolyte disturbances, and/or underlying medical problems for which they were receiving concomitant medications known to prolong the QT interval. Therapy with quinolones should be avoided in patients with known QT prolongation and/or uncorrected electrolyte disorders (hypokalemia or hypomagnesemia) and in patients treated concomitantly with class IA or III antiarrhythmic agents. Cautious use with ECG monitoring is advised in patients with other proarrhythmic conditions such as clinically significant bradycardia, congestive heart failure, acute myocardial ischemia, and atrial fibrillation. As QT prolongation may be a concentration-dependent effect, it is important that the recommended dosages or infusion rates of these drugs not be exceeded, particularly in patients with renal and/or hepatic impairment.

Quinolones may cause CNS stimulation manifested as tremors, agitation, restlessness, anxiety, confusion, hallucinations, paranoia, insomnia, toxic psychosis, and/or seizures. Benign intracranial hypertension has also been reported. Therapy with quinolones should be administered cautiously in patients with or predisposed to seizures or other CNS abnormalities. In addition, these patients should be advised to avoid the consumption of caffeine-containing products during therapy with some quinolones, most notably ciprofloxacin, enoxacin, and cinoxacin, since these agents can substantially reduce the clearance of caffeine and other methylxanthines, potentially resulting in severe CNS reactions.

Clostridioides difficile-associated diarrhea (CDAD), formerly pseudomembranous colitis, has been reported with almost all antibacterial drugs and may range from mild diarrhea to fatal colitis. The most common culprits include clindamycin and lincomycin. Antibacterial therapy alters the normal flora of the colon, leading to overgrowth of C difficile, whose toxins A and B contribute to CDAD development. Morbidity and mortality are increased with hypertoxin-producing strains of C difficile; these infections can be resistant to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea after antibacterial use. Since CDAD has been reported to occur more than 2 months after antibacterial use, careful medical history is necessary. Therapy with broad-spectrum antibacterials and other agents with significant antibacterial activity should be administered cautiously in patients with history of gastrointestinal disease, particularly colitis; pseudomembranous colitis (generally characterized by severe, persistent diarrhea and severe abdominal cramps, and sometimes associated with the passage of blood and mucus), if it occurs, may be more severe in these patients and may be associated with flares in underlying disease activity. Antibacterial drugs not directed against C difficile may need to be stopped if CDAD is suspected or confirmed. Appropriate fluid and electrolyte management, protein supplementation, antibacterial treatment of C difficile, and surgical evaluation should be started as clinically indicated.

Quinolones have been reported to prolong the QT interval of the electrocardiogram in some patients. QT prolongation may potentiate the risk of ventricular arrhythmias including ventricular tachycardia, ventricular fibrillation, and torsade de pointes. The risk appears to be greatest with grepafloxacin and sparfloxacin (both are no longer marketed in the U.S.), although cardiovascular morbidity and mortality attributable to QT prolongation have also been reported rarely with others like gatifloxacin, levofloxacin, ciprofloxacin, and ofloxacin. Reported cases have primarily occurred in patients with advanced age, cardiac disease, electrolyte disturbances, and/or underlying medical problems for which they were receiving concomitant medications known to prolong the QT interval. Therapy with quinolones should be avoided in patients with known QT prolongation and/or uncorrected electrolyte disorders (hypokalemia or hypomagnesemia) and in patients treated concomitantly with class IA or III antiarrhythmic agents. Cautious use with ECG monitoring is advised in patients with other proarrhythmic conditions such as clinically significant bradycardia, congestive heart failure, acute myocardial ischemia, and atrial fibrillation. As QT prolongation may be a concentration-dependent effect, it is important that the recommended dosages or infusion rates of these drugs not be exceeded, particularly in patients with renal and/or hepatic impairment.

Quinolones have been reported to prolong the QT interval of the electrocardiogram in some patients. QT prolongation may potentiate the risk of ventricular arrhythmias including ventricular tachycardia, ventricular fibrillation, and torsade de pointes. The risk appears to be greatest with grepafloxacin and sparfloxacin (both are no longer marketed in the U.S.), although cardiovascular morbidity and mortality attributable to QT prolongation have also been reported rarely with others like gatifloxacin, levofloxacin, ciprofloxacin, and ofloxacin. Reported cases have primarily occurred in patients with advanced age, cardiac disease, electrolyte disturbances, and/or underlying medical problems for which they were receiving concomitant medications known to prolong the QT interval. Therapy with quinolones should be avoided in patients with known QT prolongation and/or uncorrected electrolyte disorders (hypokalemia or hypomagnesemia) and in patients treated concomitantly with class IA or III antiarrhythmic agents. Cautious use with ECG monitoring is advised in patients with other proarrhythmic conditions such as clinically significant bradycardia, congestive heart failure, acute myocardial ischemia, and atrial fibrillation. As QT prolongation may be a concentration-dependent effect, it is important that the recommended dosages or infusion rates of these drugs not be exceeded, particularly in patients with renal and/or hepatic impairment.

Quinolones have been reported to prolong the QT interval of the electrocardiogram in some patients. QT prolongation may potentiate the risk of ventricular arrhythmias including ventricular tachycardia, ventricular fibrillation, and torsade de pointes. The risk appears to be greatest with grepafloxacin and sparfloxacin (both are no longer marketed in the U.S.), although cardiovascular morbidity and mortality attributable to QT prolongation have also been reported rarely with others like gatifloxacin, levofloxacin, ciprofloxacin, and ofloxacin. Reported cases have primarily occurred in patients with advanced age, cardiac disease, electrolyte disturbances, and/or underlying medical problems for which they were receiving concomitant medications known to prolong the QT interval. Therapy with quinolones should be avoided in patients with known QT prolongation and/or uncorrected electrolyte disorders (hypokalemia or hypomagnesemia) and in patients treated concomitantly with class IA or III antiarrhythmic agents. Cautious use with ECG monitoring is advised in patients with other proarrhythmic conditions such as clinically significant bradycardia, congestive heart failure, acute myocardial ischemia, and atrial fibrillation. As QT prolongation may be a concentration-dependent effect, it is important that the recommended dosages or infusion rates of these drugs not be exceeded, particularly in patients with renal and/or hepatic impairment.

Quinolones have been reported to prolong the QT interval of the electrocardiogram in some patients. QT prolongation may potentiate the risk of ventricular arrhythmias including ventricular tachycardia, ventricular fibrillation, and torsade de pointes. The risk appears to be greatest with grepafloxacin and sparfloxacin (both are no longer marketed in the U.S.), although cardiovascular morbidity and mortality attributable to QT prolongation have also been reported rarely with others like gatifloxacin, levofloxacin, ciprofloxacin, and ofloxacin. Reported cases have primarily occurred in patients with advanced age, cardiac disease, electrolyte disturbances, and/or underlying medical problems for which they were receiving concomitant medications known to prolong the QT interval. Therapy with quinolones should be avoided in patients with known QT prolongation and/or uncorrected electrolyte disorders (hypokalemia or hypomagnesemia) and in patients treated concomitantly with class IA or III antiarrhythmic agents. Cautious use with ECG monitoring is advised in patients with other proarrhythmic conditions such as clinically significant bradycardia, congestive heart failure, acute myocardial ischemia, and atrial fibrillation. As QT prolongation may be a concentration-dependent effect, it is important that the recommended dosages or infusion rates of these drugs not be exceeded, particularly in patients with renal and/or hepatic impairment.

Quinolones have been reported to prolong the QT interval of the electrocardiogram in some patients. QT prolongation may potentiate the risk of ventricular arrhythmias including ventricular tachycardia, ventricular fibrillation, and torsade de pointes. The risk appears to be greatest with grepafloxacin and sparfloxacin (both are no longer marketed in the U.S.), although cardiovascular morbidity and mortality attributable to QT prolongation have also been reported rarely with others like gatifloxacin, levofloxacin, ciprofloxacin, and ofloxacin. Reported cases have primarily occurred in patients with advanced age, cardiac disease, electrolyte disturbances, and/or underlying medical problems for which they were receiving concomitant medications known to prolong the QT interval. Therapy with quinolones should be avoided in patients with known QT prolongation and/or uncorrected electrolyte disorders (hypokalemia or hypomagnesemia) and in patients treated concomitantly with class IA or III antiarrhythmic agents. Cautious use with ECG monitoring is advised in patients with other proarrhythmic conditions such as clinically significant bradycardia, congestive heart failure, acute myocardial ischemia, and atrial fibrillation. As QT prolongation may be a concentration-dependent effect, it is important that the recommended dosages or infusion rates of these drugs not be exceeded, particularly in patients with renal and/or hepatic impairment.

Fluoroquinolones have neuromuscular blocking activity and may exacerbate muscle weakness in persons with myasthenia gravis. Postmarketing serious adverse events, including deaths and requirement for ventilatory support, have been associated with fluoroquinolones use in persons with myasthenia gravis. Fluoroquinolones should be avoided in patients with history of myasthenia gravis.

Tendonitis and ruptures of the shoulder, hand, and Achilles tendons have been reported in patients receiving quinolones, both during and after treatment. Avoid the use of these agents in patients who have a history of tendon disorders or have experienced tendinitis or tendon rupture. Therapy with quinolones should be administered cautiously in patients with patients with kidney, heart, and lung transplant, since it may delay the recognition or confound the diagnosis of a quinolone-induced musculoskeletal effect. Factors that may independently increase the risk of tendon rupture include strenuous physical activity, renal failure, and previous tendon disorders such as rheumatoid arthritis. It is recommended to discontinue these agents if, at any time during therapy, pain, inflammation or rupture of a tendon develops and institute appropriate treatment.

The use of quinolones has been associated with an increased risk of peripheral neuropathy. Monitor closely and discontinue their use in patients experiencing symptoms of peripheral neuropathy. It is recommended to avoid these agents in patients who have previously experienced peripheral neuropathy.

Tendonitis and ruptures of the shoulder, hand, and Achilles tendons have been reported in patients receiving quinolones, both during and after treatment. Avoid the use of these agents in patients who have a history of tendon disorders or have experienced tendinitis or tendon rupture. Therapy with quinolones should be administered cautiously in patients with patients with kidney, heart, and lung transplant, since it may delay the recognition or confound the diagnosis of a quinolone-induced musculoskeletal effect. Factors that may independently increase the risk of tendon rupture include strenuous physical activity, renal failure, and previous tendon disorders such as rheumatoid arthritis. It is recommended to discontinue these agents if, at any time during therapy, pain, inflammation or rupture of a tendon develops and institute appropriate treatment.

Tendonitis and ruptures of the shoulder, hand, and Achilles tendons have been reported in patients receiving quinolones, both during and after treatment. Avoid the use of these agents in patients who have a history of tendon disorders or have experienced tendinitis or tendon rupture. Therapy with quinolones should be administered cautiously in patients with patients with kidney, heart, and lung transplant, since it may delay the recognition or confound the diagnosis of a quinolone-induced musculoskeletal effect. Factors that may independently increase the risk of tendon rupture include strenuous physical activity, renal failure, and previous tendon disorders such as rheumatoid arthritis. It is recommended to discontinue these agents if, at any time during therapy, pain, inflammation or rupture of a tendon develops and institute appropriate treatment.

Tendonitis and ruptures of the shoulder, hand, and Achilles tendons have been reported in patients receiving quinolones, both during and after treatment. Avoid the use of these agents in patients who have a history of tendon disorders or have experienced tendinitis or tendon rupture. Therapy with quinolones should be administered cautiously in patients with patients with kidney, heart, and lung transplant, since it may delay the recognition or confound the diagnosis of a quinolone-induced musculoskeletal effect. Factors that may independently increase the risk of tendon rupture include strenuous physical activity, renal failure, and previous tendon disorders such as rheumatoid arthritis. It is recommended to discontinue these agents if, at any time during therapy, pain, inflammation or rupture of a tendon develops and institute appropriate treatment.

The trace elements, copper and manganese, are excreted in the bile. Copper and manganese doses may need to be adjusted, reduced, or omitted in patients with liver disease or biliary obstruction.

Crystalluria has been reported rarely during quinolone therapy. Although it is not expected to occur under normal circumstances with usual recommended dosages, patients who are dehydrated (e.g., due to severe diarrhea or vomiting) may be at increased risk and should be encouraged to consume additional amounts of liquid or given intravenous fluid to ensure an adequate urinary output. Alkalinity of the urine should be avoided, since it may also increase the risk of crystalluria. Renal function tests should be performed periodically during prolonged therapy (> 2 weeks).

The use of certain quinolones has been associated with disturbances in blood glucose homeostasis possibly stemming from effects on pancreatic beta cell ATP-sensitive potassium channels that regulate insulin secretion. Hypoglycemia and, less frequently, hyperglycemia have been reported, although the latter may also occur due to infection alone. Hypoglycemia has usually occurred in patients with diabetes receiving concomitant oral hypoglycemic agents and/or insulin. Administration of ciprofloxacin, levofloxacin, norfloxacin, and especially gatifloxacin in patients treated with sulfonylureas or other oral hypoglycemic agents has resulted in severe, refractory hypoglycemia and hypoglycemic coma. Elderly patients and patients with reduced renal function are particularly susceptible. Blood glucose should be monitored more closely whenever quinolones are prescribed to patients with diabetes. Gatifloxacin has been known to cause hypoglycemic episodes generally within the first 3 days of therapy and sometimes even after the first dose, while hyperglycemia usually occurs 4 to 10 days after initiation of therapy. Patients should be counseled to recognize symptoms of hypoglycemia such as headache, dizziness, drowsiness, nausea, tremor, weakness, hunger, excessive perspiration, and palpitations. If hypo- or hyperglycemia occur during quinolone therapy, patients should initiate appropriate remedial therapy immediately, discontinue the antibiotic, and contact their physician.

Crystalluria has been reported rarely during quinolone therapy. Although it is not expected to occur under normal circumstances with usual recommended dosages, patients who are dehydrated (e.g., due to severe diarrhea or vomiting) may be at increased risk and should be encouraged to consume additional amounts of liquid or given intravenous fluid to ensure an adequate urinary output. Alkalinity of the urine should be avoided, since it may also increase the risk of crystalluria. Renal function tests should be performed periodically during prolonged therapy (> 2 weeks).

The trace elements, copper and manganese, are excreted in the bile. Copper and manganese doses may need to be adjusted, reduced, or omitted in patients with liver disease or biliary obstruction.

The trace metals manganese, chromium, copper, selenium, and zinc are absorbed in the GI tract from dietary sources and following administration of oral supplements. GI absorption may be decreased in patients with malabsorption syndromes. Therefore, larger dosages may be required when these supplements are given orally. Parenteral administration may be appropriate.

Quinolones (except trovafloxacin, moxifloxacin, and nalidixic acid) and their metabolites are eliminated by the kidney. Patients with renal impairment may be at greater risk for adverse effects from quinolones, including nephrotoxicity, due to decreased drug clearance. Dosage adjustments may be necessary and modifications should be based on the degree of renal impairment and severity of infection in accordance with the individual product package labeling. Renal function tests should be performed periodically during therapy.

Crystalluria has been reported rarely during quinolone therapy. Although it is not expected to occur under normal circumstances with usual recommended dosages, patients who are dehydrated (e.g., due to severe diarrhea or vomiting) may be at increased risk and should be encouraged to consume additional amounts of liquid or given intravenous fluid to ensure an adequate urinary output. Alkalinity of the urine should be avoided, since it may also increase the risk of crystalluria. Renal function tests should be performed periodically during prolonged therapy (> 2 weeks).