White ciprofloxacin tablets on black background
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A new study by a team of Canadian researchers hints at a potential link between fluoroquinolone antibiotics and increased risk of panic attacks.

Although fluoroquinolones are among the most widely prescribed antibiotics, they’ve been linked to an array of side effects, including tendinitis and tendon rupture, peripheral neuropathy (a nerve condition that causes weakness, numbness, and pain in the hands and feet), and central nervous system effects. These associations have led the Food and Drug Administration (FDA) to revise its black box warning labels for fluoroquinolones several times. Despite frequent case reports of panic attacks following fluoroquinolone use, no large-scale studies have looked at the potential association.

The study, published late last week in the Journal of Antimicrobial Chemotherapy by researchers from Western University in Ontario, included a systematic review and meta-analysis of 12 relevant studies and an analysis of individual case safety reports (ICSRs) identified in the FDA’s Adverse Event Reporting System (FAERS) database. The 12 studies, published from 2004 to 2024, included four clinical trials and eight papers describing 11 case reports. The FAERS analysis compared ICSRs for fluoroquinolones (ciprofloxacin, levofloxacin, and moxifloxacin) and two comparator drugs—azithromycin and trimethoprim/sulfamethoxazole.

Increased risk compared with other antibiotics

The prevalence of panic attacks in the four clinical trials ranged from 0.5% to 1.8%, with wide confidence intervals, which suggest a high level of uncertainty. Among the 1,022 panic attacks identified in FAERS, fluoroquinolones were associated with a sixfold increase in reports of panic attacks compared with azithromycin and a 12-fold increase compared with trimethoprim-sulfamethoxazole. Ciprofloxacin showed the strongest signal, with double the risk of other fluoroquinolones. 

The authors acknowledge that a causal relationship can’t be determined because of their reliance on spontaneous reports to FAERS, which are unverified. But they say the findings align with previous research and represent the most comprehensive evidence to date on the potential association between fluoroquinolones and increased risk of panic attacks.

“While these findings from spontaneous reporting databases are hypothesis-generating, they highlight panic attacks as a distinct clinical phenotype that warrants further investigation using population-level longitudinal data,” they wrote.