When to avoid fluoroquinolones? A Guide to Safe Prescribing

October 13, 2025 •

3 min read

Despite their efficacy, fluoroquinolone use decreased by 26.7% in the U.S. between 2015 and 2019 due to growing safety concerns. Understanding when to avoid fluoroquinolones is critical for patient safety due to their association with disabling and potentially permanent side effects.

Quick Summary

Fluoroquinolones should be avoided for uncomplicated infections when safer alternatives exist. High-risk groups and those with a history of adverse reactions, specific comorbidities, or taking interacting drugs should not use them.

Key Points

Reserve for Serious Infections: The FDA recommends reserving fluoroquinolones for infections with no alternative treatment options due to risks outweighing benefits for uncomplicated sinusitis, bronchitis, and UTIs.
High-Risk Populations: Avoid use in patients over 60, those taking corticosteroids, organ transplant recipients, and individuals with a history of aortic aneurysm or certain connective tissue disorders.
Tendon and Nerve Damage: Fluoroquinolones carry black box warnings for increased risk of tendonitis, tendon rupture, and potentially permanent peripheral neuropathy.
Cardiovascular Risks: A serious risk includes aortic aneurysm and dissection, particularly in older patients and those with pre-existing hypertension.
Central Nervous System Effects: CNS side effects can include seizures, psychosis, anxiety, confusion, and suicidal thoughts.
Drug and Food Interactions: Avoid concurrent intake with dairy, antacids, or supplements containing calcium, iron, or zinc, as they impair absorption.
History of Reaction: A previous serious adverse reaction to any quinolone or fluoroquinolone is a direct contraindication for future use.

The Shifting Landscape of Fluoroquinolone Use

Fluoroquinolones, including ciprofloxacin, levofloxacin, and moxifloxacin, are powerful, broad-spectrum antibiotics. Historically used widely, concerns about serious side effects have led to decreased prescriptions. Regulatory bodies now emphasize reserving these drugs for more severe infections when alternative treatments are not suitable.

FDA Black Box Warnings: A History of Increasing Caution

The FDA has issued several black box warnings for fluoroquinolones, highlighting the potential for serious and sometimes irreversible side effects. Initial warnings in 2008 focused on tendinitis and tendon rupture risk, especially in older adults, those on corticosteroids, and transplant recipients. Subsequent warnings in 2011, 2013, 2016, and 2018 addressed risks including worsening myasthenia gravis symptoms, permanent peripheral neuropathy, disabling musculoskeletal and nervous system side effects, aortic aneurysm and dissection, blood sugar disturbances, and mental health issues.

Key Patient Populations and Conditions for Avoidance

Certain individuals face a higher risk of adverse effects from fluoroquinolones. Avoidance is generally recommended in:

Patients with a history of serious adverse reactions to any quinolone or fluoroquinolone.
Individuals over 60 years old.
Patients concurrently taking corticosteroids.
Organ transplant recipients.
Those with a history of aortic aneurysm or conditions that increase risk, such as hypertension, Marfan syndrome, or Ehlers-Danlos syndrome.
Patients with epilepsy, a history of seizures, or other central nervous system (CNS) disorders.
Pregnant and breastfeeding individuals, unless the benefit clearly outweighs the risk and no alternatives exist.
Children, with use restricted to specific, severe infections due to potential musculoskeletal risks.

Uncomplicated Infections: When a Fluoroquinolone is a Poor First Choice

Professional guidelines strongly discourage using fluoroquinolones for common, uncomplicated infections when other effective options are available. This includes:

Acute Bacterial Sinusitis (ABS)
Acute Bacterial Exacerbation of Chronic Bronchitis (ABECB)
Uncomplicated Urinary Tract Infections (UTIs)

In these cases, fluoroquinolones should be considered only if first-line treatments fail, the patient has allergies, or there is documented resistance.

Drug and Food Interactions to Manage

Fluoroquinolone absorption can be reduced by products containing multivalent cations found in dairy products, fortified juices, antacids, iron, and zinc. Separate administration by at least two hours. Additionally, fluoroquinolones can interact with medications like warfarin, theophylline, certain antidepressants, and NSAIDs, potentially increasing the risk of adverse effects.

Comparison of Common Fluoroquinolones and Their Alternatives

While all fluoroquinolones carry similar risks, their effectiveness against specific bacteria varies. The emphasis remains on using safer alternative antibiotics whenever appropriate.


Infection Type	Safer First-Line Alternatives	When Fluoroquinolones Might Be Considered (Second-Line)
Uncomplicated UTI (Cystitis)	Nitrofurantoin, Trimethoprim/sulfamethoxazole (if resistance is low), Fosfomycin	Failure of first-line agents, allergies, or known resistance
Acute Sinusitis	Amoxicillin, Amoxicillin/clavulanate, Doxycycline	Penicillin allergy, failure of first-line therapy
Community-Acquired Pneumonia	Amoxicillin, Doxycycline, Macrolides (e.g., Azithromycin)	Comorbidities, recent antibiotic use, or severe infection
Skin Infections (Mild)	Amoxicillin/clavulanate, Cefalexin, Cloxacillin	For moderate-to-severe infections or specific pathogens

Conclusion

Prescribing fluoroquinolones requires careful consideration of the risks versus benefits. Given the potential for severe, long-lasting adverse effects like tendon injury, nerve damage, CNS issues, and aortic problems, they are no longer recommended as a first choice for many common infections. Healthcare providers should practice antibiotic stewardship and reserve fluoroquinolones for situations where alternatives are unsuitable or ineffective. Patients must be informed about the risks and advised to seek immediate medical attention if they experience symptoms of serious side effects.

For more information on FDA warnings, you can visit the FDA's Drug Safety Communication page.

Frequently Asked Questions

For uncomplicated UTIs, the FDA advises that the risks of disabling and potentially permanent side effects from fluoroquinolones (like tendon, muscle, joint, and nerve damage) outweigh the benefits. Safer and effective alternatives like nitrofurantoin or fosfomycin are recommended as first-line treatments.

Patients over the age of 60 are at a higher risk for serious side effects from fluoroquinolones, including tendon rupture and aortic aneurysm. It should be prescribed with special caution and only when other antibiotics are not appropriate.

The primary signs are a sudden onset of pain, swelling, or inflammation in a tendon, most commonly the Achilles tendon. If you experience this, you should stop taking the medication immediately, rest the area, and contact your doctor.

Fluoroquinolones are generally contraindicated during pregnancy and not recommended while breastfeeding. They should only be used if the clinical benefit clearly exceeds the potential risk and no safer alternative is available.

You should avoid taking fluoroquinolones with dairy products (milk, yogurt) or calcium-fortified juices. Also, avoid antacids or supplements containing calcium, magnesium, aluminum, iron, or zinc for at least two hours before and after your dose, as they can make the antibiotic less effective.

FQAD refers to a constellation of disabling and potentially permanent side effects that can occur together, affecting the tendons, muscles, joints, nerves (peripheral neuropathy), and central nervous system (anxiety, confusion, memory problems).

No. While they share a class-wide risk of serious side effects, individual drugs like ciprofloxacin, levofloxacin, and moxifloxacin have different potencies against various bacteria. For example, ciprofloxacin is often more active against P. aeruginosa, while moxifloxacin has better activity against S. pneumoniae.