PDR Health


Generic name: Norfloxacin

What is Noroxin?

Noroxin is a prescription medication used to treat bacterial infections. It belongs to a class of antibiotics called fluoroquinolones.


Health Benefits

Noroxin is used to treat various bacterial infections, including:

Urinary tract infections



Skin infections

Bone and joint infections

Noroxin may also be used for purposes not listed in this medication guide.

Side Effects

Common side effects of Noroxin include:







Noroxin can also cause serious side effects, including:

Tendon rupture or inflammation of the tendons (tendinitis)

Peripheral neuropathy (nerve damage)

Serious skin reactions

You should not use Noroxin if you are allergic to norfloxacin or similar antibiotics, such as ciprofloxacin (Cipro), gemifloxacin (Factive), levofloxacin (Levaquin), moxifloxacin (Avelox), ofloxacin (Floxin), or others.

To make sure Noroxin is safe for you, tell your doctor if you have ever had:

A history of joint or tendon problems

Kidney disease

Myasthenia gravis


Noroxin is available in 400 mg tablets. The usual adult dose is one tablet every 12 hours for seven to 14 days.

The recommended dosage for children is 10 mg/kg (up to 400 mg) every 12 hours for 10 days.


Noroxin can interact with other medications, vitamins, or herbs you may be taking. An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well.

To help avoid interactions, your doctor should manage all of your medications carefully. Be sure to tell your doctor about all medications, vitamins, or herbs you’re taking. To find out how this drug might interact with something else you’re taking, talk to your doctor or pharmacist.

Noroxin and Alcohol

You should avoid drinking alcohol while taking Noroxin. Drinking alcohol can increase certain side effects of the drug.

Pregnancy and Noroxin

Noroxin is a category C pregnancy drug. That means two things:

Research in animals has shown adverse effects to the fetus when the mother takes the drug. There haven’t been enough studies done in humans to be certain how this medication might affect the fetus.

You should always speak with your doctor before you start, stop, or change any prescribed part of your care plan or treatment. Noroxin may be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It’s not known whether norfloxacin passes into breast milk or could harm a nursing baby. You should not breastfeed while you are taking Noroxin.

Mechanism of Action

Noroxin works by inhibiting an enzyme called DNA gyrase. This prevents the bacteria from duplicating their DNA, which ultimately kills them.


Noroxin is rapidly absorbed from the gastrointestinal tract. The bioavailability is about 70%.


The half-life of a drug is the time it takes for your body to eliminate half of the drug. The half-life of Noroxin is 4-5 hours.

Alternatives to Noroxin

Alternatives for treating bacterial infections include other antibiotics, such as:


Cephalexin (Keflex)


If you’re allergic to norfloxacin or can’t take it for another reason, your doctor may prescribe a different antibiotic. These alternatives may include:

Azithromycin (Zithromax)

Ciprofloxacin (Cipro)

You may also be interested in:

Augmentin vs Amoxicillin


If you take too much Noroxin, call your doctor or go to the nearest emergency room right away.

Symptoms of an overdose may include:







Chemical Structure

Norfloxacin is a synthetic chemotherapeutic agent that belongs to the class of drugs known as quinolone antibiotics. Chemically, it is 5-norbornyl-2,3-dihydro-7-fluoro-2-(methoxyimino)-1,4-dioxo-1H-isoquinolinecarboxylic acid. The molecular formula is C16H18FN3O3 and the molecular weight is 319.32.

Long-term Effects

In some people, Noroxin can cause a condition that results in the breakdown of skeletal muscle tissue. This condition may be more likely to occur in older adults and in people who have kidney disease or poorly controlled hypothyroidism (underactive thyroid).