It is well-known and well-documented that fluoroquinolones weaken and destroy musculoskeletal tissues–especially, but not limited to, tendons. 

Additionally, it is known that fluoroquinolones cause neurological problems, and can lead to painful and debilitating peripheral neuropathy. (In 2013, fluoroquinolone warning labels were updated to note that Cipro/ciprofloxacin, Levaquin/levofloxacin, Avelox/moxifloxacin, and Floxin/ofloxacin can cause permanent and disabling peripheral neuropathy.)

Given that fluoroquinolones disproportionately affect the tissues in joints, and that they also adversely affect nerves (causing painful neuropathy), it’s not surprising that fluoroquinolone antibiotic use is associated with Carpal Tunnel Syndrome (CTS)–a medical condition that includes “pain, numbness, and tingling, in the thumb, index finger, middle finger, and the thumb side of the ring fingers,” as well as weakness and muscle wasting.

Both CTS and fluoroquinolone-use are common in America, and researchers Jasmine Z. Cheng, Mohit Sodhi, Mahyar Etminan, and Bruce C. Carleton, examined how they are related in “Fluoroquinolone Use and Risk of Carpal Tunnel Syndrome: A Pharmacoepidemiologic Study” published in the journal Clinical Infectious Diseases in August, 2017.

In “Fluoroquinolone Use and Risk of Carpal Tunnel Syndrome: A Pharmacoepidemiologic Study” the researchers found that, “Any use of FQ within the year prior to CTS diagnosis was associated with a 34% and 36% increased risk of CTS in the primary and sensitivity analyses, respectively” and that:

“The results of our study are consistent with an increase in the risk of CTS with FQs. The risk was consistent among all risk periods with a slight increase among past users, which may be due to the longer period elapsed for CTS to manifest itself. FQ-related neurotoxicity can persist cumulatively in relation to exposure levels [8, 9]. The exact mechanism by which this occurs is unknown [9], but proposed models include direct nerve inflammation and ischemia from toxic metabolite and free radical formation [10], and FQ-induced tendonitis/tendinopathy causing mechanical compression upon the adjacent nerves (eg, median nerve) that share the carpal tunnel [11]. Reports of nerve biopsy studies on patients who have experienced FQ adverse events have revealed significantly reduced nerve fiber density consistent with small fiber neuropathy, which may be a potential mechanism of CTS [12]. Although neurotoxicity is the second most commonly reported adverse event, with several studies documenting FQ association with central and peripheral nerve damage [8, 9], this is the first large-scale study exploring the relationship between FQs and CTS.”

CTS is a malady that affects thousands of people and has societal costs in the millions of dollars. In “Fluoroquinolone Use and Risk of Carpal Tunnel Syndrome: A Pharmacoepidemiologic Study” the researchers note that:

“CTS is a disease of significant societal burden with a prevalence of 5% and incidence of up to 2.3 per 1000 person-years [4, 5]. CTS causes loss of function and decreased quality of life for individual patients, and also comprises a large cumulative drain on healthcare and socioeconomic resources from loss of productivity and worker’s compensation claims [6]. One study of 4443 CTS claimants in Washington State estimated a cumulative socioeconomic cost of US$197–$382 million over 6 years for this cohort alone [6].”

Fluoroquinolones are increasing the risk of CTS in millions of people (20+ million prescriptions for fluoroquinolones are written each year). Are doctors or patients aware that they are increasing the patient’s chances of CTS–a painful, debilitating, and costly condition–when fluoroquinolone antibiotics are taken? I doubt it, but they should be.

Please spread the word about how dangerous fluoroquinolones are by sharing posts, news articles, and research articles that connect fluoroquinolones with other illnesses. It wouldn’t occur to most people that a commonly prescribed class of antibiotics could be connected with CTS, psychiatric illness, pain, pseudotumor cerebri, tendon damage and ruptures, or multi-symptom chronic illnesses. But fluoroquinolones ARE connected with those, and other, diseases and syndromes. Articles like “Fluoroquinolone Use and Risk of Carpal Tunnel Syndrome: A Pharmacoepidemiologic Study” help to provide evidence of the extensive damage that fluoroquinolones do, and I am grateful to the researchers who examined the connections. Please spread the word so that doctors and patients alike are informed. Thank you.