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Floxin IV Side Effects

Generic name: ofloxacin

Medically reviewed by Last updated on Feb 27, 2024.

Note: This document contains side effect information about ofloxacin. Some dosage forms listed on this page may not apply to the brand name Floxin IV.

Applies to ofloxacin: oral tablet.


Oral route (Tablet)

Fluoroquinolones, including ofloxacin, are associated with disabling and potentially irreversible serious adverse reactions that have occurred together, including tendinitis and tendon rupture, peripheral neuropathy, and CNS effects. Discontinue ofloxacin and avoid use of fluoroquinolones in patients with these serious adverse reactions. Reserve use of ofloxacin for patients with no alternative treatment options for acute exacerbation of chronic bronchitis or uncomplicated cystitis. Fluoroquinolones, including ofloxacin, may exacerbate muscle weakness in persons with myasthenia gravis. Avoid in patients with known history of myasthenia gravis.

Serious side effects of Floxin IV

Along with its needed effects, ofloxacin (the active ingredient contained in Floxin IV) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking ofloxacin:

Less common


Incidence not known

Other side effects of Floxin IV

Some side effects of ofloxacin may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

For Healthcare Professionals

Applies to ofloxacin: intravenous solution, oral tablet.


This drug was generally well tolerated, and side effects were mild in nature. In clinical trials, 11% of patients experienced side effects. Therapy was discontinued due to side effects in 4% of patients.[Ref]


The onset of pseudomembranous colitis symptoms has been reported during or after antimicrobial therapy.

Dyspepsia, flatulence, and constipation have also been reported during postmarketing experience. According to some authorities, pseudomembranous colitis was reported very rarely.[Ref]

Common (1% to 10%): Nausea, diarrhea, vomiting, abdominal pain and cramps, dry mouth, flatulence, gastrointestinal distress, constipation

Uncommon (0.1% to 1%): Abdominal pain

Rare (0.01% to 0.1%): Enterocolitis (sometimes hemorrhagic)

Frequency not reported: Dyspepsia

Postmarketing reports: Pseudomembranous colitis, gastrointestinal hemorrhage, intestinal perforation, hiccough, pyrosis, painful oral mucosa, pancreatitis, stomatitis[Ref]

Nervous system

Common (1% to 10%): Headache, dizziness, dysgeusia, somnolence

Uncommon (0.1% to 1%): Vertigo

Rare (0.01% to 0.1%): Paresthesia, parosmia

Very rare (less than 0.01%): Extrapyramidal symptoms or other disorders of muscular coordination, tinnitus, hearing loss

Frequency not reported: Seizures, cognitive change, syncope, tremor, decreased hearing acuity, sensory axonal polyneuropathy, sensorimotor axonal polyneuropathy, idiopathic intracranial hypertension

Postmarketing reports: Peripheral neuropathy (may be irreversible), peripheral sensory neuropathy, convulsion, peripheral sensory motor neuropathy, ataxia, incoordination, exacerbation of myasthenia gravis, exacerbation of extrapyramidal disorders, dysphasia, lightheadedness, taste disturbance, smell disturbance, hearing disturbance, equilibrium disturbance, dyskinesia, ageusia, hearing impaired[Ref]

Seizures were more likely to occur in elderly patients and in patients with renal dysfunction.

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

A survey reported 6 cases of peripheral neuropathy associated with this drug. In 1 case, a 49-year-old female developed diffuse numbness, "pins and needles" sensation, burning pain, memory loss, visual impairment, joint pain, palpitations, altered sense of smell, insomnia, tinnitus, and severe panic attacks, with some symptoms persisting after 3 years.

Disturbances of taste, smell, hearing, and equilibrium were usually reversible after the drug was stopped.

Syncope and tremor have also been reported during postmarketing experience. According to some authorities, peripheral sensory neuropathy, peripheral sensory motor neuropathy, and convulsion were reported very rarely.[Ref]


Common (1% to 10%): Increased serum creatinine, increased BUN

Very rare (less than 0.01%): Acute renal failure

Frequency not reported: Nephrogenic diabetic insipidus

Postmarketing reports: Renal calculi, renal failure, interstitial nephritis, acute interstitial nephritis[Ref]


Common (1% to 10%): Elevated AST, elevated ALT

Rare (0.01% to 0.1%): Elevated liver enzymes (ALT, AST, LDH, GGT, alkaline phosphatase), elevated blood bilirubin

Very rare (less than 0.01%): Cholestatic jaundice

Postmarketing reports: Hepatic dysfunction (including hepatic necrosis, jaundice [cholestatic or hepatocellular], hepatitis [including severe cases]), hepatic failure (including fatal cases), elevated liver function tests (including GGT, LDH, bilirubin), severe liver injury (including acute liver failure [sometimes fatal])[Ref]

Severe liver injury (including cases of acute liver failure [sometimes fatal]) has been reported, primarily in patients with underlying liver disorders.[Ref]


Common (1% to 10%): Anemia, leukopenia, leukocytosis, neutropenia, neutrophilia, increased band forms, lymphocytopenia, eosinophilia, lymphocytosis, thrombocytopenia, thrombocytosis, elevated erythrocyte sedimentation rate

Very rare (less than 0.01%): Hemolytic anemia

Postmarketing reports: Aplastic anemia, hemorrhage, pancytopenia, agranulocytosis, reversible bone marrow depression, thrombotic thrombocytopenic purpura, petechiae, prothrombin time prolongation, ecchymosis/bruising, bone marrow failure[Ref]

Anemia (including hemolytic), leukopenia, and thrombocytopenia have also been reported during postmarketing experience.[Ref]


IV formulation:

-Common (1% to 10%): Injection site reactions (including phlebitis, swelling, erythema, pain)[Ref]


Rare (0.01% to 0.1%): Tendinitis

Very rare (less than 0.01%): Arthralgia, myalgia, tendon rupture (e.g., Achilles tendon)

Postmarketing reports: Muscular weakness, rhabdomyolysis, myopathy, muscle tear, muscle rupture, ligament rupture, arthritis[Ref]

Tendinitis and tendon rupture have also been reported during postmarketing experience. Tendon rupture (sometimes bilateral) has been reported within 48 hours of starting therapy.[Ref]


Rare (0.01% to 0.1%): Tachycardia, hypotension

Frequency not reported: Cardiac arrest, hypertension, palpitations, vasodilation

Postmarketing reports: Cerebral thrombosis, hypotension/shock, ventricular arrhythmias, ECG QT prolonged, torsades de pointes[Ref]

Torsades de pointes were reported primarily in patients with risk factors for QT prolongation. This drug was associated with 2 cases of torsades de pointes reported to the US FDA between 1996 and 2001.

Tachycardia has also been reported during postmarketing experience. Tachycardia and hypotension have occurred during IV infusion (during postmarketing experience); in very rare cases, such a decrease in blood pressure has been severe.[Ref]


Postmarketing reports: Anaphylactic reactions/shock, anaphylactoid reactions/shock, serum sickness[Ref]

According to some authorities, anaphylactic reaction and anaphylactoid reaction were reported rarely and anaphylactic shock and anaphylactoid shock were reported very rarely.[Ref]


Common (1% to 10%): External genital pruritus in women, vaginitis, vaginal discharge, glucosuria, proteinuria, alkalinuria, hyposthenuria, hematuria, pyuria

Frequency not reported: Dysuria; urinary frequency; urinary retention; dysmenorrhea; menorrhagia; metrorrhagia; burning, irritation, pain, and rash of the female genitalia

Postmarketing reports: Vaginal candidiasis, albuminuria, candiduria, anuria, polyuria


-Frequency not reported: Crystalluria, cylindruria[Ref]

Hematuria has also been reported during postmarketing experience.

Crystalluria and cylindruria have been reported with other quinolones.[Ref]


Common (1% to 10%): Rash, pruritus

Rare (0.01% to 0.1%): Urticaria, hyperhidrosis, pustular rash

Very rare (less than 0.01%): Erythema multiforme, toxic epidermal necrolysis, drug eruption, vascular purpura, vasculitis (sometimes leading to skin necrosis)

Frequency not reported: Angioedema, diaphoresis

Postmarketing reports: Hyperpigmentation, Stevens-Johnson syndrome, erythema nodosum, exfoliative dermatitis, photosensitivity/phototoxicity reaction, vesiculobullous eruption, purpura, acute generalized exanthematous pustulosis, drug rash[Ref]

A 75-year-old male developed toxic epidermal necrolysis and died of complications after receiving a total of 23.6 g of this drug orally over 51 days.

Angioedema, erythema multiforme, and toxic epidermal necrolysis have also been reported during postmarketing experience. According to some authorities, angioedema was reported rarely and photosensitivity was reported very rarely.[Ref]


Ophthalmologic abnormalities (including cataracts and multiple punctate lenticular opacities) have been reported with other quinolones.[Ref]

Common (1% to 10%): Visual disturbances

Uncommon (0.1% to 1%): Eye irritation

Frequency not reported: Photophobia

Postmarketing reports: Diplopia, nystagmus, blurred vision, conjunctivitis, uveitis


-Frequency not reported: Ophthalmologic abnormalities (including cataracts, multiple punctate lenticular opacities)[Ref]


Common (1% to 10%): Fatigue, chest pain, fever, trunk pain, elevated alkaline phosphatase

Uncommon (0.1% to 1%): Fungal infection, pathogen resistance

Rare (0.01% to 0.1%): Hot flushes

Frequency not reported: Asthenia, chills, malaise, edema, extremity pain, pain, thirst, weight loss

Postmarketing reports: Elevated serum triglycerides, elevated serum cholesterol, elevated serum potassium, pyrexia, pain (including back, chest, extremities)[Ref]

Asthenia has also been reported during postmarketing experience.[Ref]


Common (1% to 10%): Pharyngitis

Uncommon (0.1% to 1%): Cough, nasopharyngitis

Rare (0.01% to 0.1%): Dyspnea, bronchospasm

Frequency not reported: Respiratory arrest, rhinorrhea, epistaxis

Postmarketing reports: Allergic pneumonitis, pulmonary edema, stridor[Ref]

Dyspnea (including severe dyspnea) and bronchospasm have also been reported during postmarketing experience.[Ref]


Hyperglycemia and hypoglycemia (especially in diabetic patients on insulin or oral hypoglycemic agents) have also been reported during postmarketing experience. Attacks of porphyria have been reported in patients with porphyria.[Ref]

Common (1% to 10%): Decreased appetite, hyperglycemia, hypoglycemia

Rare (0.01% to 0.1%): Anorexia

Postmarketing reports: Acidosis, hypoglycemic coma, porphyria attacks[Ref]


In 1 patient, a psychotic reaction to this drug presented with irritability, restlessness, insomnia, and irrational fear. The reaction was treated with haloperidol and resolved within 48 hours. One study suggests that the central nervous system effects of quinolones may be due to an interaction with the benzodiazepine-gamma-aminobutyric acid receptor complex and may be controlled by benzodiazepine administration.

Agitation, nervousness, psychotic reactions, and nightmares have also been reported during postmarketing experience.[Ref]

Common (1% to 10%): Insomnia, nervousness, sleep disorders

Uncommon (0.1% to 1%): Agitation

Rare (0.01% to 0.1%): Anxiety, depression, confusional state, psychotic disorder/reactions (e.g., hallucination), nightmares

Frequency not reported: Dream abnormality, euphoria, hallucinations

Postmarketing reports: Restlessness, psychotic disorder and depression with self-endangering behavior (including suicidal ideation, suicide attempt), suicidal thoughts or acts, disorientation, paranoia, phobia, aggressiveness/hostility, manic reaction, emotional lability[Ref]


1. Todd PA, Faulds D. Ofloxacin: a reappraisal of its antimicrobial activity, pharmacology, and therapeutic use. Drugs. 1991;42:825-76.

2. Smith JT. Ofloxacin, a bactericidal antibacterial. Chemotherapy. 1991;37:2-13.

3. Guay DR, Opsahl JA, McMahon FG, Vargas R, Matzke GR, Flor S. Safety and pharmacokinetics of muliple doses of intravenous ofloxacin in healthy volunteers. Antimicrob Agents Chemother. 1992;36:308-12.

4. Product Information. Floxin (ofloxacin). Ortho McNeil Pharmaceutical. 2001;PROD.

5. Cerner Multum, Inc. UK Summary of Product Characteristics.

6. Marchbanks CR, Dudley MN, Flor S, Beals B. Pharmacokinetics and safety of single rising doses of ofloxacin in healthy volunteers. Pharmacotherapy. 1992;12:45-9.

7. Basista MP. Randomized study to evaluate efficacy and safety of ofloxacin vs trimethoprim and sulfamethoxazole in treatment of uncomplicated urinary tract infection. Urology. 1991;37:21-7.

8. Fostini R, Girelli M, Dalle VP, Benedetti M, Recchia G. Safety profile of ofloxacin in elderly patients. Drugs Exp Clin Res. 1988;14:393-5.

9. Giamarellou H, Tsagarakis J. Efficacy and tolerance of oral ofloxacin in treating various infections. Drugs. 1987;34:119-23.

10. Wendel GD, Cox SM, Bawdon RE, Theriot SK, Heard MC, Nobles BJ. A randomized trial of ofloxacin versus cefoxitin and doxycycline in the outpatients treatment of acute salpingitis. Am J Obstet Gynecol. 1991;164:1390-6.

11. Dan M, Samra Z. Clostridium difficile colitis associated with ofloxacin therapy. Am J Med. 1989;87:479.

12. Tack KJ, Smith JA. The safety profile of ofloxacin. Am J Med. 1989;87:s78-81.

13. Unseld E, Ziegler G, Gemeinhardt A, Janssen U, Klotz U. Possible interaction of fluoroquinolones with benzodiazepine-GABA-receptorn complex. Br J Clin Pharmacol. 1990;30:63-70.

14. Fennig S, Mauas L. Ofloxacin-induced delirium. J Clin Psychiatry. 1992;53:137-8.

15. Kohler RB, Arkins N, Tack KJ. Accidental overdose of intravenous ofloxacin with benign outcome. Antimicrob Agents Chemother. 1991;35:1239-40.

16. Getenet JC, Croisile B, Vighetto A, et al. Idiopathic intracranial hypertension after ofloxacin treatment. Acta Neurol Scand. 1993;87:503-4.

17. Thomas RJ, Regan DR. Association of a tourette-like syndrome with ofloxacin. Ann Pharmacother. 1996;30:138-41.

18. Traeger SM, Bonfiglio MF, Wilson JA, Martin BR, Nackes NA. Seizures associated with ofloxacin therapy. Clin Infect Dis. 1995;21:1504-6.

19. Walton GD, Hon JK, Mulpur TG. Ofloxacin-induced seizure. Ann Pharmacother. 1997;31:1475-7.

20. Cohen JS. Peripheral neuropathy associated with fluoroquinolones. Ann Pharmacother. 2001;35:1540-7.

21. Hofer T, Becker EW, Weigand K, Berg PA. Demonstration of sensititzed lymphocytes to trimethoprim/sulfamethoxazole and ofloxacin in a patient with cholestatic hepatitis. J Hepatol. 1992;15:262-3.

22. Blum A. Ofloxacin-induced acute severe hepatitis. South Med J. 1991;84:1158.

23. Carro PG, Huidobro MLL, Zabala AP, Vicente EM. Fatal subfulminant hepatic failure with ofloxacin. Am J Gastroenterol. 2000;95:1606.

24. Huminer D, Cohen JD, Majadla R, Dux S. Hypersensitivity vasculitis due to ofloxacin. Br Med J. 1989;299:303.

25. Pace JL, Gatt P. Fatal vasculitis associated with ofloxacin. BMJ. 1989;299:658.

26. Baril L, Maisonobe T, JassonMolinier M, Haroche J, Bricaire F, Caumes E. Acute rhabdomyolysis during treatment with ofloxacin - A case report. Clin Infect Dis. 1999;29:1598-9.

27. Khaliq Y, Zhanel GG. Fluoroquinolone-Associated Tendinopathy: A Critical Review of the Literature. Clin Infect Dis. 2003;36:1404-1410.

28. Frothingham R. Rates of torsades de pointes associated with ciprofloxacin, ofloxacin, levofloxacin, gatifloxacin, and moxifloxacin. Pharmacotherapy. 2001;21:1468-72.

29. Owens RC Jr, Ambrose PG. Torsades de pointes associated with fluoroquinolones. Pharmacotherapy. 2002;22:663-8; discussion 668-72.

30. Berger RE. Rates of torsades de pointes associated with ciprofloxacin, ofloxacin, levofloxacin, gatifloxacin, and moxifloxacin. J Urol. 2005;174:165.

31. Briasoulis A, Agarwal V, Pierce WJ. QT Prolongation and Torsade de Pointes Induced by Fluoroquinolones: Infrequent Side Effects from Commonly Used Medications. Cardiology. 2011;120:103-110.

32. Tsuda S, Kato K, Karashima T, Inou YH, Sasai Y. Toxic pustuloderma induced by ofloxacin. Acta Derm Venereol. 1993;73:382-4.

33. Melde SL. Ofloxacin: a probable cause of toxic epidermal necrolysis. Ann Pharmacother. 2001;35:1388-90.

34. Maunz G, Conzett T, Zimmerli W. Cutaneous vasculitis associated with fluoroquinolones. Infection. 2009;37:466-8.

35. Bharani A, Kumar H. Diabetes inspidus induced by ofloxacin. BMJ. 2001;323:547.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.