Norfloxacin: How does it work? Precautions, Presentation and Side Effects

It is an antibiotic that belongs to the class of medicines called quinolones.

How does this medication work? What will he do for me?

It is used to treat infections caused by certain types of bacteria. It is most often used to treat urinary tract infections (bladder). Norfloxacin works by killing some types of bacteria that can cause these infections.

This medication may be available under multiple brands and / or in different forms. Any specific brand of this medication may not be available on all forms or approved for all conditions listed here.


Also, some forms of this medication can not be used for all conditions that are treated here.

Your doctor may have suggested this medication for conditions other than those listed in these medication information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, talk to your doctor.

Do not stop taking this medication without consulting your doctor.

Do not give this medicine to anyone else, even if they have the same symptoms you have. It can be harmful for people to take this medicine if their doctor has not prescribed it.

What form (s) does this medication have?

Each white, oval, biconvex, film-coated tablet, marked and engraved “APO 400” on one side and smooth on the other, contains 400 mg of norfloxacin.

Non-medicinal ingredients:

  • Crospovidona
  • Magnesium stearate
  • Colloidal silicon dioxide
  • Hydroxypropyl cellulose
  • Hydroxypropyl methylcellulose
  • Polyethylene glycol
  • Titanium dioxide

How should I use this medication?

The usual recommended dose for adults is 400 mg twice a day, taken with a glass of water at least one hour before or 2 hours after a meal or milk. You should drink plenty of fluids (water or juice) every day unless your doctor tells you otherwise.

Norfloxacin should not be taken within 2 hours of taking iron, zinc supplements or multivitamins that contain them. The dose of norfloxacin may vary depending on the circumstances and the condition being treated.

Many things can affect the dose of medication a person needs, such as body weight, other medical conditions and other medications.

If your doctor has recommended a different dose than the previous one, do not change the way you are taking the medication without consulting your doctor.

To consider:

  • It is important that you take this medication exactly as prescribed by your doctor.
  • Finish all this medication, even if you have started to feel better.
  • If you miss a dose, take it as soon as possible and continue your usual schedule.
  • If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule.
  • Do not take a double dose to make up for the one you forgot.
  • If you are not sure what to do after skipping a dose, contact your doctor or pharmacist.
  • Store this medication at room temperature, protect it from light and moisture and keep it out of the reach of children.
  • Do not dispose of medications in wastewater (for example, in the sink or in the toilet) or in household waste.
  • Ask your pharmacist how to get rid of medications that are no longer needed or are no longer valid.

Who should NOT take this medicine?

Do not take Norfloxacin if you are allergic to it, to other Quinolones (for example, Ciprofloxacin, Nalidixic Acid) or to any other component of the medicine.

What side effects are possible with Norfloxacin?

Many medications can cause side effects. A side effect is an unwanted response to a medication when taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be controlled, and some may go away on their own over time.

Contact your doctor if you experience these side effects and are severe or bothersome. Your pharmacist can advise you on the management of side effects:

  • Diarrhea (mild)
  • Dizziness or lightheadedness
  • Headache
  • Acidity
  • Increased sensitivity of the skin to the sun
  • Loss of appetite
  • Nausea
  • Problems sleeping
  • Vomiting

Although most of the side effects listed below do not happen very often, they could cause serious problems if you do not see your doctor or seek medical attention.

Check with your doctor as soon as possible if you experience any of the following side effects:

  • Blisters of the skin.
  • Increase muscle weakness
  • Pain in the joints or muscles.
  • Mood changes such as anxiety or depression
  • Pain, swelling or rupture of a tendon.
  • Skin burning sensation.
  • Itchy skin, rash, redness or swelling.
  • Symptoms of high blood sugar levels (for example, frequent urination, increased thirst, excessive food intake, unexplained weight loss, poor wound healing, infections, odor of fruity breath).
  • Symptoms of low blood sugar (for example, cold sweat, pale and cold skin, headache, fast heartbeat, weakness) changes in vision.

Stop taking the medication and seek immediate medical attention if any of the following symptoms occur:

  • Diarrhea (watery, severe or bloody)
  • Signs of a severe allergic reaction (swelling of the face or throat, hives or difficulty breathing).
  • Signs of a severe skin reaction (eg, blistering, peeling, rash covering a large area of ​​the body, a rapidly spreading rash or rash combined with fever or discomfort).

Some people may experience side effects other than those listed.

Check with your doctor if you notice any symptoms that bother you while taking this medicine.

Other precautions or warnings for Norfloxacin

Before you start using a medication, be sure to tell your doctor about any medical conditions or allergies you have. You can have any medication you are taking, whether you are pregnant or breastfeeding, and any other important information about your health.

These factors can affect the way you should use this medicine.

Notice of studies conducted in Canada

Health Canada has issued new restrictions regarding the use of Norfloxacin

Symptoms that the patient should watch:

  • Blood sugar levels: Norfloxacin can cause a loss of control of blood sugar levels and glucose tolerance may change.
  • People with diabetes may find it necessary to control their blood sugar level more often while using this medication.
  • It is also known that people without diabetes experience high or low blood sugar levels while taking Norfloxacin.
  • If you have diabetes or are at risk of developing diabetes, talk to your doctor about how this medicine may affect your medical condition, how your medical condition may affect the dose and effectiveness of this medicine, and if any special monitoring is needed.
  • If you experience signs of high blood sugar levels (odor of fruity breath, weight loss, increased thirst or increased need to urinate) or low blood sugar levels (cold sweat, pale cold skin, pain head or weakness) contact your doctor.
  • Diarrhea: People who take this medicine may develop diarrhea caused by an infection with C. difficile bacteria. If you have loose, watery and bloody stools, with or without fever or stomach cramps, after taking Norfloxacin, get medical attention as soon as possible.
  • Diarrhea caused by C. difficile infection can cause serious health problems if not treated properly.
  • Kidneys: Norfloxacin is transmitted from the body mainly by the kidney. If you have reduced kidney function, talk to your doctor about how this medication may affect your medical condition, how your medical condition may affect the dosage, the effectiveness of this medication, and if special monitoring is needed.
  • Neuromuscular disorders: Norfloxacin can cause muscle weakness increase for people with Myasthenia Grave (an autoimmune disorder that causes muscle weakness).

If you have Myasthenia Grave, talk with your doctor about how this medication may affect your medical condition, how your medical condition may affect the dosage and effectiveness of this medication, and if any special monitoring is needed.

  • Attacks: it can be considered that it is not a frequent occurrence, since there have been no seizures with this medicine.

If you have a history of epilepsy or medical conditions that increase the risk of seizures, talk with your doctor about how this medication may affect your medical condition, how your medical condition may affect the dosage and effectiveness of this medication, and whether there is any control special necessary.

  •  If you have seizures while taking this medication, stop taking it and seek medical attention immediately.
  • Sunburn: People who take Norfloxacin are more prone to sunburn. Avoid exposure to excessive sunlight, including sunlamps and tanning beds, and use sunscreen with a minimum SPF of 15.
  • Stop taking the medication if there is solar sensitivity.
  • Tendons: Rarely, people who take Norfloxacin have experienced tendinitis and / or tendon rupture, especially if they are also taking corticosteroids. If you experience pain or swelling in the joints or tendons, contact your doctor as soon as possible.
  • Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
  • Breastfeeding: Norfloxacin can pass into breast milk. If you are a nursing mother and you are taking this medication, it can affect your baby. Consult your doctor if you should continue breastfeeding.
  • Children: The safety and efficacy of this medication have not been established for children under 16 years of age.

What other drugs may interact with this medicine?

There may be an interaction between Norfloxacin and any of the following:

  • Aminophylline, Amiodarone, Acids containing aluminum, Calcium or Magnesium (do not take within 2 hours of norfloxacin).
  • Anti-psychotics (eg, Chlorpromazine, Clozapine, Haloperidol, Olanzapine, Quetiapine), Risperidone)
  • Caffeine-based supplements and multivitamins containing calcium (do not take Norfloxacin within 2 hours)
  • Steroids with Chloroquine, Colchicine, or Cortico (eg, Dexamethasone, Hydrocortisone, Prednisone) Cyclosporin
  • Drugs (eg, chlorpropamide, glipizide, glyburide, insulin, metaformin, nateglinide, rosiglitazone) didanosine (do not take within 2 hours of norfloxacin)
  • Iron supplements, such as Ferrous Sulfate, or Multivitamins that contain iron (do not take Norfloxacin within 2 hours)
  • Antibiotics (eg, Clarithromycin, Erythromycin)
  • Methadone
  • Mifepristona
  • Anti inflammatory drugs with Steroids (eg Diclofenac, Ibuprofen, Ketoprofen, Naproxen).
  • Selective Serotonin Reuptake Inhibitors (SSRIs, eg, Citalopram, Duloxetine, Fluoxetine, Paroxetine, Sertraline).
  • Serotonin antagonists (antiemetic medications, eg, Granisetron, Ondansetron) Supplements or multivitamin that contain Zinc (do not take within 2 hours of Norfloxacin).

If you are taking any of these medications, talk to your doctor or pharmacist.

Depending on your specific circumstances, your doctor may want you to:

  • Stop taking one of the medications
  • Change one of the medications to another
  • Change the way you take one or both medications, or leave everything as it is.

An interaction between two medications does not always mean you should stop taking one of them.

If you have any of the symptoms described above, do not hesitate or lose time to consult, talk with your doctor about how drug interactions are handled or controlled.

Medications other than those mentioned above may interact with this medication.

Tell your doctor or prescriber about all prescription, over-the-counter (OTC), and herbal medications you are taking.

Also tell them about any supplements you’re taking. Because caffeine, alcohol, nicotine in cigarettes or illegal drugs can affect the action of many medications, you should inform your doctor if you use them.