Norfloxacin Side Effects

For the Consumer

Applies to norfloxacin: oral tablet

As well as its needed effects, norfloxacin may cause unwanted side effects that require medical attention.

Major Side Effects

If any of the following side effects occur while taking norfloxacin, check with your doctor immediately:

• Chest pain or discomfort
• chills
• diarrhea
• discouragement
• fast, irregular, pounding, or racing heartbeat or pulse
• feeling sad or empty
• fever
• flushing or redness of the skin
• hives or welts, itching, or skin rash
• increased sweating
• irritability
• irritation or soreness of the mouth
• itching of the rectal area
• lack of appetite
• loss of interest or pleasure
• nausea
• pain and inflammation at the joints
• pain or discomfort in the arms, jaw, back, or neck
• redness of the skin
• shortness of breath
• sweating
• swelling of the foot or hand
• swelling of the stomach
• tingling of the fingers
• tiredness
• trouble with concentrating
• trouble with sleeping
• unusually warm skin
• vomiting

• Abdominal or stomach cramps or tenderness
• anxiety
• back, leg, or stomach pains
• black, tarry stools
• bleeding gums
• blistering, peeling, or loosening of the skin
• bloating
• blood in the urine or stools
• blurred vision
• bone pain
• burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
• clay-colored stools
• cold sweats
• constipation
• cool, pale skin
• cough or hoarseness
• cracks in the skin
• dark-colored urine
• decreased frequency or amount of urine
• diarrhea, watery and severe, which may also be bloody
• difficulty with breathing, chewing, swallowing, or talking
• difficulty with moving
• dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
• double vision
• drooping eyelids
• dry mouth
• dry skin
• false sense of well-being
• fever with or without chills
• fruit-like breath odor
• general body swelling
• general feeling of tiredness or weakness
• greatly decreased frequency of urination or amount of urine
• headache
• inability to move the arms and legs
• increased blood pressure
• increased hunger
• increased sensitivity of the skin to sunlight
• increased thirst
• increased urination
• indigestion
• irregular or slow heart rate
• large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
• light-colored stools
• loss of heat from the body
• lower back or side pain
• mood or mental changes
• mood swings
• muscle aching or cramping
• muscle pain or stiffness
• muscle weakness
• nightmares
• nosebleeds
• numbness or tingling in the hands, feet, or lips
• pain or burning while urinating
• pain, inflammation, or swelling in the calves, shoulders, or hands
• pain, swelling, or redness in the joints
• painful or difficult urination
• pains in the stomach, side, or abdomen, possibly radiating to the back
• personality changes
• pinpoint red spots on the skin
• puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• red skin lesions, often with a purple center
• red, irritated eyes
• red, swollen skin
• scaly skin
• seeing, hearing, or feeling things that are not there
• seizures
• severe sunburn
• severe tiredness
• shakiness and unsteady walk
• slurred speech
• sore throat
• sores, ulcers, or white spots on the lips or in the mouth
• sores, welting, or blisters
• stomach pain, continuing
• sudden decrease in the amount of urine
• sudden numbness and weakness in the arms and legs
• swelling of the face, fingers, or lower legs
• swelling or inflammation of the mouth
• swollen glands
• tightness in the chest
• unexplained weight loss
• unpleasant breath odor
• unsteadiness, awkwardness, trembling, or other problems with muscle control or coordination
• unusual behavior, such as disorientation to time or place, failure to recognize people, hyperactivity, or restlessness
• unusual bleeding or bruising
• unusual tiredness or weakness
• unusual weight loss
• vomiting of blood
• weakness in the arms, hands, legs, or feet
• weight gain
• yellowing of the eyes or skin

Minor Side Effects

Some norfloxacin side effects may not need any medical attention. As your body gets used to the medicine these side effects may disappear. Your health care professional may be able to help you prevent or reduce these side effects, but do check with them if any of the following side effects continue, or if you are concerned about them:

• Lack or loss of strength

• Acid or sour stomach
• belching
• bitter taste
• cramps
• excess air or gas in the stomach or intestines
• full feeling
• heartburn
• heavy bleeding
• pain
• passing gas
• sleepiness or unusual drowsiness
• stomach discomfort, upset, or pain
• weight loss

• Change in taste
• continuing ringing or buzzing or other unexplained noise in the ears
• hearing loss
• itching of the vagina or outside genitals
• loss of taste
• pain during sexual intercourse
• seeing double
• thick, white curd-like vaginal discharge without odor or with mild odor
• uncontrolled eye movements

For Healthcare Professionals

Applies to norfloxacin: oral tablet

General

This drug was generally well tolerated and side effects were mild. Side effects were reported in 6.5% of subjects receiving single doses and 3.6% of subjects receiving multiple doses.^[Ref]

Gastrointestinal

The onset of pseudomembranous colitis symptoms may occur during or after antimicrobial treatment.

Pseudomembranous colitis and pancreatitis have also been reported during postmarketing experience.^[Ref]

Common (1% to 10%): Nausea, abdominal cramping
Uncommon (0.1% to 1%): Abdominal pain, anal/rectal pain, constipation, diarrhea, dry mouth, dyspepsia/heartburn, flatulence, loose stools, vomiting, abdominal swelling, mouth ulcer, pruritus ani
Rare (0.01% to 0.1%): Pseudomembranous colitis, pancreatitis
Postmarketing reports: Stomatitis

Quinolones:
-Frequency not reported: Intestinal perforation^[Ref]

Nervous system

Cases of sensory or sensorimotor axonal polyneuropathy (affecting small and/or large axons) resulting in paresthesias, hypoesthesias, dysesthesias, and weakness have been reported.

Seizures reported in association with this drug have occurred, generally in older patients. A patient with myasthenia gravis had her condition deteriorate during 2 different courses of this drug.

Paresthesia, polyneuropathy (including Guillain-Barre syndrome), tinnitus, and exacerbation of myasthenia gravis have also been reported during postmarketing experience.^[Ref]

Common (1% to 10%): Headache, dizziness
Uncommon (0.1% to 1%): Tingling of the fingers, somnolence/drowsiness, bitter taste
Rare (less than 0.1%): Peripheral sensory neuropathy/sensory axonal polyneuropathy, peripheral sensory motor neuropathy/sensorimotor axonal polyneuropathy, paresthesia, polyneuropathy, Guillain-Barre syndrome, seizures, tinnitus, exacerbation of myasthenia gravis
Frequency not reported: Dysesthesia, altered taste
Postmarketing reports: Generalized seizures, convulsions, myoclonus, tremors, peripheral neuropathy (may be irreversible), ataxia, hypoesthesia, hearing loss, dysgeusia, hypertonia, dysarthria, dysphasia

Quinolones:
-Postmarketing reports: Dysphasia^[Ref]

Hypersensitivity

Uncommon (0.1% to 1%): Allergies/allergic reactions
Rare (0.01% to 0.1%): Anaphylactic/anaphylactoid reactions
Postmarketing reports: Hypersensitivity reactions (including anaphylactoid reactions, anaphylaxis, angioedema, dyspnea, vasculitis, urticaria, arthritis, arthralgia, myalgia, interstitial nephritis, DRESS syndrome)^[Ref]

Renal

Interstitial nephritis has also been reported during postmarketing experience.^[Ref]

Rare (0.01% to 0.1%): Interstitial nephritis
Frequency not reported: Decreased renal function, nephrotic syndrome (which has occurred in patients treated with high doses), increased BUN/serum urea, increased serum creatinine
Postmarketing reports: Renal failure

Quinolones:
-Frequency not reported: Renal calculi^[Ref]

Hepatic

Hepatitis has also been reported during postmarketing experience.^[Ref]

Common (1% to 10%): Elevated ALT, elevated AST, cholestatic hepatitis, hepatitis
Frequency not reported: Eosinophilic necrotizing granulomatous hepatitis
Postmarketing reports: Jaundice (including cholestatic jaundice), elevated liver function tests, hepatic failure (including fatal cases)

Quinolones:
-Frequency not reported: Hepatic necrosis^[Ref]

Hematologic

Eosinophilia was reported in 7.5% of 1 study population. Leukopenia and neutropenia have been reported in up to 1% of patients. Hemolytic anemia has sometimes been associated with glucose-6-phosphate dehydrogenase deficiency.

Leukopenia, neutropenia, hemolytic anemia, prothrombin time prolongation, and thrombocytopenia have also been reported during postmarketing experience.^[Ref]

Common (1% to 10%): Eosinophilia, decreased WBC, decreased neutrophil count, decreased platelet count
Uncommon (0.1% to 1%): Decreased hematocrit, decreased hemoglobin, increased eosinophils, leukopenia, neutropenia, thrombocytopenia, prothrombin time prolongation
Rare (0.01% to 0.1%): Hemolytic anemia
Postmarketing reports: Agranulocytosis

Quinolones:
-Postmarketing reports: Agranulocytosis, prothrombin time prolongation^[Ref]

Musculoskeletal

Common (1% to 10%): Rhabdomyolysis
Uncommon (0.1% to 1%): Bursitis, back pain
Rare (0.01% to 0.1%): Tendinitis, tendosynovitis, myalgia/muscle pains, joint pains, joint inflammation
Very rare (less than 0.01%): Tendon rupture (e.g., Achilles tendon)
Frequency not reported: Bilateral arthritis of the ankles
Postmarketing reports: Elevated creatine kinase, muscle spasms^[Ref]

Quinolones, including this drug, have been associated with ruptures of the shoulder, hand, Achilles, and other tendons resulting in disability or requiring surgical repair. Elderly patients and patients concomitantly using corticosteroids may be at increased risk.

Renal transplant patients have an increased risk of Achilles tendinitis and rupture over the general population. Quinolone use has been shown to increase that risk further in this population (12% in quinolone-treated patients versus 7% in patients not treated).

There have been 23 reports of tendinitis submitted to the Australian Adverse Drug Reactions Committee (ADRAC) between 2006 and 2008, including reports of Achilles tendonitis, tendon rupture, and tendon pain and swelling. The reports were primarily in male patients (15 cases) older than 56 years who used ciprofloxacin for 2 to 14 days. In 19 of the reported cases, a fluoroquinolone (generally ciprofloxacin) was the primary suspect; however, details of concomitant serious medical conditions were not documented in most of the reports.

Tendinitis and tendon rupture have also been reported during postmarketing experience.^[Ref]

Other

Common (1% to 10%): Asthenia, elevated alkaline phosphatase
Uncommon (0.1% to 1%): Fever, fatigue, chest pain, foot or hand swelling, chills, edema
Rare (0.01% to 0.1%): Tiredness
Frequency not reported: Weakness, elevated LDH

Quinolones:
-Postmarketing reports: Elevated serum triglycerides, elevated serum cholesterol, elevated serum potassium^[Ref]

Dermatologic

Uncommon (0.1% to 1%): Rash, pruritus, hyperhidrosis, erythema, urticaria
Rare (0.01% to 0.1%): Petechiae, hemorrhagic bullae/papules with vasculitis, skin reactions, exfoliative dermatitis, toxic epidermal necrolysis (Lyell's syndrome), erythema multiforme, Stevens-Johnson syndrome, photosensitivity, angioedema
Frequency not reported: Systemic contact dermatitis
Postmarketing reports: Leukocytoclastic vasculitis, drug rash with eosinophilia and systemic symptoms (DRESS syndrome), photosensitivity/phototoxicity reactions, periorbital erythema

Quinolones:
-Frequency not reported: Erythema nodosum, photosensitivity (phototoxic reactions, photosensitization with vesiculation, redness, swelling, discoloration)^[Ref]

Rash, toxic epidermal necrolysis, Stevens-Johnson syndrome, erythema multiforme, pruritus, and exfoliative dermatitis have also been reported during postmarketing experience. Rash has been reported as the most common side effect during postmarketing experience.

A 70-year-old male developed systemic contact dermatitis, an itchy papulopustular eruption from the thighs to the abdomen, after 3 days of therapy with this drug. The patient was treated with prednisone for 15 days. A patch test 1 month later resulted in a reaction to quinolone mix.

Photosensitivity has been reported in patients extensively exposed to sunlight or sunbeds during ongoing therapy with quinolone-like agents.^[Ref]

Genitourinary

Crystalluria has occurred in patients taking doses greater than 1200 mg/day and whose urine pH was 7 to 7.8.

Crystalluria and vaginal candidiasis have also been reported during postmarketing experience.^[Ref]

Common (1% to 10%): Increased urine protein
Uncommon (0.1% to 1%): Dysmenorrhea, renal colic, crystalluria
Rare (0.01% to 0.1%): Vaginal candidiasis
Frequency not reported: Glycosuria, vaginal swelling
Postmarketing reports: Proteinuria

Quinolones:
-Postmarketing reports: Crystalluria, albuminuria, candiduria, cylindruria, hematuria, vaginal candidiasis^[Ref]

Cardiovascular

Uncommon (0.1% to 1%): Myocardial infarction, palpitation
Frequency not reported: Tachycardia, ECG QT prolonged, cardiovascular collapse
Postmarketing reports: Prolonged QTc interval, ventricular arrhythmia (including torsade de pointes)

Quinolones:
-Postmarketing reports: Postural hypotension^[Ref]

Ocular

Uncommon (0.1% to 1%): Blurred vision
Rare (0.01% to 0.1%): Visual disturbance, increased lacrimation
Postmarketing reports: Diplopia, uveitis, nystagmus, conjunctivitis, eye pain/irritation, hemophthalmia

Quinolones:
-Postmarketing reports: Nystagmus, visual disturbances^[Ref]

Visual disturbances have also been reported during postmarketing experience.^[Ref]

Metabolic

Uncommon (0.1% to 1%): Anorexia
Rare (0.01% to 0.1%): Loss of appetite
Postmarketing reports: Dysglycemia

Quinolones:
-Frequency not reported: Acidosis
-Postmarketing reports: Symptomatic hypoglycemia, elevated blood glucose^[Ref]

Respiratory

Quinolones:
-Frequency not reported: Hiccough^[Ref]

Psychiatric

Uncommon (0.1% to 1%): Anxiety, depression, insomnia, sleep disturbances
Rare (0.01% to 0.1%): Mood changes, nervousness, irritability, euphoria, disorientation, hallucinations, confusion, psychic disturbances, psychotic reactions

Quinolones:
-Frequency not reported: Manic reactions^[Ref]

Psychic disturbances (including psychotic reactions) and confusion have also been reported during postmarketing experience.^[Ref]

It is possible that some side effects of norfloxacin may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.

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