From the Guidelines
Levaquin (levofloxacin) commonly causes several side effects, with the most frequent being nausea, diarrhea, headache, and dizziness, as reported in a study published in 2011 1.
Common Side Effects
- Nausea
- Diarrhea
- Headache
- Dizziness Some patients also experience:
- Insomnia
- Constipation
- Abdominal pain
Serious Side Effects
More concerning side effects that require medical attention include:
- Tendon inflammation or rupture, particularly in the Achilles tendon, which is more common in older adults, those taking corticosteroids, or people with kidney disease, as noted in a study from 2017 1
- Peripheral neuropathy (nerve damage) resulting in pain, burning, tingling, numbness, or weakness in the extremities
- Photosensitivity reactions, making skin more sensitive to sunlight Rarely, Levaquin can cause:
- Serious allergic reactions
- Liver problems
- Changes in blood sugar levels
- Central nervous system effects like confusion, hallucinations, or seizures, especially in elderly patients If you experience severe side effects, particularly tendon pain, weakness, or signs of an allergic reaction, contact your healthcare provider immediately.
Risk Factors
Certain factors increase the risk of these side effects, including:
- Advanced age
- Antecedent steroid therapy
- Underlying diseases, such as hypercholesterolemia, gout, rheumatoid arthritis, end-stage renal disease/dialysis, and renal transplantation, as reported in a study from 2011 1 These side effects occur because Levaquin belongs to the fluoroquinolone class of antibiotics, which can affect connective tissues and nervous system function in some individuals.
From the FDA Drug Label
The most common adverse drug reactions (≥ 3%) are nausea, headache, diarrhea, insomnia, constipation, and dizziness
- Common side effects of levofloxacin include:
- Nausea
- Headache
- Diarrhea
- Insomnia
- Constipation
- Dizziness The most common adverse drug reactions leading to discontinuation with the 250 and 500 mg doses were gastrointestinal (1.4%), primarily nausea (0.6%); vomiting (0.4%); dizziness (0.3%); and headache (0.2%) 2.
From the Research
Common Side Effects of Levaquin
- Tendinitis and tendon rupture are among the most common side effects associated with Levaquin, a fluoroquinolone antibiotic 3, 4, 5, 6, 7
- The risk of tendinopathy is considered a fluoroquinolone class-wide toxicity, but data suggest that levofloxacin may possess a higher propensity to cause tendon damage relative to other fluoroquinolones 5
- Patient-specific risk factors for fluoroquinolone-associated tendinopathy include older age, receipt of concomitant corticosteroid therapy, presence of renal dysfunction, and history of solid organ transplantation 5
Tendon Rupture Risk
- Levofloxacin has been shown to exhibit a significant increased risk of tendon ruptures, particularly Achilles tendon rupture, in some studies 4, 6, 7
- The risk of tendon rupture associated with levofloxacin is exposure-dependent, with higher doses and longer durations being most commonly associated with tendinopathy 5
- Other antibiotics, such as cephalexin, may also exhibit an increased risk of tendon ruptures, which may be due to confounding by indication bias rather than a direct effect of the antibiotic on tendon health 6
Clinical Presentation and Onset
- Fluoroquinolone-induced tendinopathy can result in long-term sequelae, including chronic pain and mobility restrictions, and may warrant surgery 5
- The majority of fluoroquinolone-related suspected tendonitis and tendon rupture tend to occur within a few days or one month of treatment initiation 3
- Clinical presentation of levofloxacin-associated tendinopathy may include bilateral heel pain, swelling, and marked tenderness with mild palpation of the Achilles tendons 4