Levaquin Leva-Pak Side Effects

Generic Name: levofloxacin

Note: This page contains information about the side effects of levofloxacin. Some of the dosage forms included on this document may not apply to the brand name Levaquin Leva-Pak.

Not all side effects for Levaquin Leva-Pak may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

For the Consumer

Applies to levofloxacin: oral solution, oral syrup, oral tablet

Other dosage forms:

In addition to its needed effects, some unwanted effects may be caused by levofloxacin (the active ingredient contained in Levaquin Leva-Pak). In the event that any of these side effects do occur, they may require medical attention.

You should check with your doctor immediately if any of these side effects occur when taking levofloxacin:

More common
  • Diarrhea
  • Abdominal or stomach cramps or pain (severe)
  • agitation
  • blisters
  • confusion
  • diarrhea (watery and severe) which may also be bloody
  • feeling that others can hear your thoughts or control your behavior
  • fever
  • pain, inflammation, or swelling in the calves of the legs, shoulders, or hands
  • redness and swelling of the skin
  • seeing, hearing, or feeling things that are not there
  • sensation of burning on the skin
  • severe mood or mental changes
  • skin rash, itching, or redness
  • trembling
  • unusual behavior
Incidence not known
  • Black, tarry stools
  • blurred vision
  • burning, numbness, tingling, or painful sensations
  • convulsions
  • cough
  • dark-colored urine
  • difficulty with breathing
  • difficulty with chewing, talking, or swallowing
  • drooping eyelids
  • fast or irregular heartbeat
  • general body swelling
  • hives
  • hoarseness
  • joint or muscle pain
  • muscle cramps, spasms, pain, or stiffness
  • peeling or loosening of the skin
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • severe dizziness
  • severe tiredness
  • tightness in the chest
  • unsteadiness or awkwardness
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • vision changes
  • voice changes
  • weakness in the arms, hands, legs, or feet

Some of the side effects that can occur with levofloxacin may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

Less common
  • Abdominal or stomach pain or discomfort
  • change in taste
  • constipation
  • dizziness
  • drowsiness
  • headache
  • lightheadedness
  • nausea
  • nervousness
  • trouble sleeping
  • vaginal itching and discharge
  • vomiting
Incidence not known
  • Feeling faint
  • feeling of warmth or heat
  • flushing or redness of the skin, especially on the face and neck
  • sweating

For Healthcare Professionals

Applies to levofloxacin: compounding powder, intravenous solution, oral solution, oral tablet


The most frequently reported side effects included nausea, headache, diarrhea, insomnia, constipation, and dizziness. Therapy was discontinued due to adverse effects in 4.3% of patients overall (3.8% treated with 250 mg and 500 mg doses; 5.4% treated with 750 mg dose). The most common side effects leading to discontinuation were gastrointestinal (primarily nausea, vomiting), dizziness, and headache.


During one study, Clostridium difficile diarrhea occurred in 11 of 490 study patients (2.2%) receiving levofloxacin (the active ingredient contained in Levaquin Leva-Pak)

Common (1% to 10%): Nausea (7%), diarrhea (5%), constipation (3%), abdominal pain (2%), dyspepsia (2%), vomiting (2%)
Uncommon (0.1% to 1%): Anorexia, gastroenteritis, pancreatitis, glossitis, gastritis, esophagitis, stomatitis, pseudomembranous/Clostridium difficile colitis
Frequency not reported: Dry mouth, dysphagia, flatulence, gastrointestinal hemorrhage, tongue edema, gastroesophageal reflux, melena, taste perversion, intestinal perforation, intestinal obstruction

Nervous system

Common (1% to 10%): Headache (6%), dizziness (3%)
Uncommon (0.1% to 1%): Convulsions, hyperkinesias, hypertonia, paresthesia, somnolence, tremor, vertigo, abnormal gait, syncope
Rare (less than 0.1%): Sensory or sensorimotor axonal polyneuropathy (resulting in paresthesias, hypoesthesias, dysesthesias, weakness)
Frequency not reported: Abnormal coordination, coma, hypoesthesia, involuntary muscle contractions, hyperesthesia, paralysis, speech disorder, stupor, encephalopathy, leg cramps, ataxia, migraine, seizures, intracranial hypertension
Postmarketing reports: Abnormal electroencephalogram (EEG), exacerbation of myasthenia gravis, anosmia, ageusia, parosmia, dysgeusia, encephalopathy (isolated reports), dysphonia, pseudotumor cerebri, hypoacusis, tinnitus, peripheral neuropathy (may be irreversible)

One survey reported 33 cases of peripheral neuropathy associated with levofloxacin, ranging in severity from mild and reversible to severe and persistent. In one case, a 51-year-old female developed "electrical" sensations, numbness, allodynia, multiple severe tendinitis, partial tendon rupture, impaired memory, confusion, and impaired concentration, with some symptoms persisting after 1 year.


Common (1% to 10%): Insomnia (4%)
Uncommon (0.1% to 1%): Abnormal dreaming, agitation, anxiety, confusion, depression, hallucination, nightmare, sleep disorder
Frequency not reported: Paroniria, nervousness, aggressive reaction, delirium, emotional lability, impaired concentration, manic reaction, mental deficiency, toxic psychoses, withdrawal syndrome
Postmarketing reports: Psychosis, paranoia, suicide attempt (isolated reports), suicidal ideation (isolated reports)


A 78-year-old female developed toxic epidermal necrolysis 2 days after parenteral levofloxacin (the active ingredient contained in Levaquin Leva-Pak) therapy. The rash initially manifested as an erythematous rash, blistering, and mucosal sloughing but progressed to exfoliation involving three-quarters of the patient's body surface area including mucosa. A positive Nikolsky sign was noted.

A 15-year-old male developed fatal toxic epidermal necrolysis taking levofloxacin for 9 days. The rash progressed over 40 hours to involve 80% of his body surface area with a positive Nikolsky sign and involvement of the eyes and oral, nasal, and perianal mucosa.

Common (1% to 10%): Rash (2%), pruritus (1%)
Uncommon (0.1% to 1%): Urticaria
Frequency not reported: Dry skin, increased sweating, skin disorder, skin exfoliation, skin ulceration, erythematous rash, alopecia, maculopapular rash, erythema nodosum, eczema
Postmarketing reports: Photosensitivity/phototoxicity reaction, bullous eruptions (including Stevens-Johnson syndrome, toxic epidermal necrolysis, erythema multiforme), leukocytoclastic vasculitis


Achilles tendon rupture occurred in 4 of 489 study patients (3217 treatment days) after 1 to 10 days of levofloxacin (the active ingredient contained in Levaquin Leva-Pak) treatment.

Severe rhabdomyolysis occurred in a 77-year-old female after 6 days of oral levofloxacin therapy. She developed acute renal failure (serum creatinine 678 micromole/L), hyperkalemia (6.8 micromole/L), anuria, elevated creatine kinase (30,400 international units/L), myoglobinemia (86,000 mcg/L), and acute hepatic cytolysis (SGOT 555 international units/L, SGPT 249 international units/L). The fluid/electrolyte disorders and creatine kinase and myoglobin levels improved with hemodialysis; however, the patient died of a myocardial infarction and respiratory failure after 13 days.

Uncommon (0.1% to 1%): Arthralgia, myalgia, skeletal pain, tendinitis
Frequency not reported: Arthritis, arthrosis, pathological fracture, osteomyelitis, synovitis, muscle weakness, tendon disorder
Postmarketing reports: Tendon rupture, muscle injury (including rupture), increased muscle enzymes, rhabdomyolysis


Levofloxacin was associated with 13 cases of torsade de pointes reported to the FDA between 1996 and 2001.

The risk of arrhythmias may be lessened by avoiding use in patients with hypokalemia, significant bradycardia, or concurrent treatment with Class IA or III antiarrhythmic agents.

An 88-year-old woman developed a prolonged QTc interval while being treated with levofloxacin (the active ingredient contained in Levaquin Leva-Pak) 500 mg once a day. The QTc interval increased from 450 msec to 577 msec by the fourth day of treatment. Levofloxacin was discontinued after the patient experienced runs of ventricular tachycardia. The QTc interval then decreased to 437 msec two days after discontinuing levofloxacin.

A 65-year-old woman with hypokalemia (2.8 mEq/L), hypomagnesemia (1.5 mEq/L), and renal insufficiency (Scr 7.7 mg/dL, BUN 34 mg/dL) developed a QTc interval of 605 ms (baseline 435-485 ms), several episodes of torsade de pointes, and cardiac arrest after 3 days of levofloxacin 250 mg/day IV. The QTc interval decreased to 399 ms and no further arrhythmias occurred after discontinuation of levofloxacin and electrolyte replacement.

Hypotension has been associated with rapid or bolus IV infusion.

Uncommon (0.1% to 1%): Cardiac arrest, palpitation, phlebitis, ventricular arrhythmia, ventricular tachycardia
Frequency not reported: Angina pectoris, arrhythmia, atrial fibrillation, bradycardia, cardiac failure, cerebrovascular disorder, circulatory failure, coronary thrombosis, heart block, hypertension, aggravated hypertension, hypotension, myocardial infarction, postural hypotension, purpura, supraventricular tachycardia, tachycardia, deep thrombophlebitis, vasculitis, ventricular fibrillation
Postmarketing reports: Vasodilation, QT interval prolongation/prolonged electrocardiogram QT, tachycardia, torsade de pointes


Common (1% to 10%): Chest pain (1%), edema (1%), moniliasis (1%)
Frequency not reported: Asthenia, fever, malaise, rigors, substernal chest pain, ascites, changed temperature sensation, ear disorder (unspecified), enlarged abdomen, hot flashes, gangrene, influenza-like symptoms, leg pain, multiple organ failure, earache, abscess, herpes simplex, bacterial infection, viral infection, otitis media, sepsis, pain, fatigue, face edema, flushing, back pain, aggravated condition, fungal infection
Postmarketing reports: Multi-organ failure, pyrexia


Uncommon (0.1% to 1%): Abnormal hepatic function, increased hepatic enzymes, increased alkaline phosphatase
Frequency not reported: Acute hepatocellular injury, cholecystitis, cholelithiasis, hepatic coma, hepatic necrosis, bilirubinemia
Postmarketing reports: Severe hepatotoxicity (including acute hepatitis and fatal events), hepatic failure (including fatal cases), hepatitis, jaundice

A 74-year-old female developed hepatotoxicity and significant increases in AST (4962 units/L), ALT (7071 units/L), alkaline phosphatase (90 units/L), and total bilirubin (2.5 mg/dL) after starting levofloxacin therapy. Levels returned to normal within a week after discontinuation.

Severe hepatotoxicity usually occurred within 14 days (most within 6 days) after starting levofloxacin and most cases were not associated with hypersensitivity. The majority of fatal hepatotoxicity cases occurred in patients 65 years or older and most were not associated with hypersensitivity.


Uncommon (0.1% to 1%): Allergic reaction
Postmarketing reports: Hypersensitivity reactions (sometimes fatal and including anaphylactic/anaphylactoid reactions, anaphylactic shock, serum sickness, angioneurotic edema)


Common (1% to 10%): Dyspnea (1%)
Uncommon (0.1% to 1%): Epistaxis
Frequency not reported: Rhinitis, sinusitis, pharyngitis, bronchitis, chronic obstructive airway disease, laryngitis, pleurisy, pneumonitis, upper respiratory tract infection, asthma, cough, hemoptysis, hiccough, hypoxia, pleural effusion, pulmonary embolism, respiratory insufficiency, airway obstruction, ARDS, aspiration, bronchospasm, emphysema, pneumonia, pneumothorax, pulmonary collapse, pulmonary edema, respiratory depression, respiratory disorder
Postmarketing reports: Allergic pneumonitis (isolated reports)


Uncommon (0.1% to 1%): Anemia, granulocytopenia, thrombocytopenia
Frequency not reported: Decreased lymphocytes, abnormal WBCs (unspecified), abnormal platelets, agranulocytosis, hematoma, leukocytosis, lymphadenopathy, decreased prothrombin, purpura, thrombocythemia
Postmarketing reports: Hemolytic anemia, eosinophilia, leukopenia, pancytopenia, aplastic anemia, prothrombin time prolonged, international normalized ratio prolonged


Uncommon (0.1% to 1%): Abnormal renal function, acute renal failure
Frequency not reported: Renal calculi, allergic interstitial nephritis
Postmarketing reports: Interstitial nephritis

A 73-year-old male developed vasculitis and acute renal failure within 3 days of initiating oral levofloxacin. Symptoms included significantly decreased urine output (0.5 L/d to 0.7 L/d), palpable purpura, erythematous skin lesions, and increased serum creatinine (6.4 mg/dL) and BUN (190 mg/dL). The condition resolved within 4 weeks after discontinuation of levofloxacin. Due to the possibility that this may have been an allergic reaction, rechallenge was not attempted.


A 79-year-old male with type 2 diabetes mellitus developed severe hypoglycemia (blood glucose 6 mg/dL) and became unresponsive 6 hours after receiving one dose of intravenous levofloxacin (the active ingredient contained in Levaquin Leva-Pak) 250 mg. Blood glucose levels subsequently ranged between 40 to 159 mg/dL with dextrose doses and infusions; however, he did not regain consciousness and expired 2 days later.

Uncommon (0.1% to 1%): Hyperglycemia, hyperkalemia, hypoglycemia
Frequency not reported: Decreased blood glucose, hypomagnesemia, thirst, aggravated diabetes mellitus, dehydration, hypokalemia, gout, hypernatremia, hypophosphatemia, increased lactate dehydrogenase, weight decrease, fluid overload, hyponatremia, increased nonprotein nitrogen, acidosis, symptomatic hypoglycemia, elevated serum triglycerides, elevated serum cholesterol, electrolyte abnormalities


Common (1% to 10%): Vaginitis (1%)
Uncommon (0.1% to 1%): Genital moniliasis
Frequency not reported: Dysmenorrhea, hematuria, dysuria, oliguria, urinary incontinence, urinary retention, leukorrhea, genital pruritus, ejaculation failure, impotence, albuminuria, candiduria, crystalluria, cylindruria, vaginal candidiasis, urinary tract infection


Frequency not reported: Ophthalmologic abnormalities (including cataracts, multiple punctate lenticular opacities), abnormal vision, eye pain, nystagmus, conjunctivitis
Postmarketing reports: Vision disturbance (including diplopia), reduced visual acuity, blurred vision, scotomata


Frequency not reported: Carcinoma


Common (1% to 10%): Injection site reactions (1%)
Frequency not reported: Injection site pain, injection site inflammation

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.