Inclusion Criteria:

Arm 1:

• Treatment with oral and/or intravenous FQ antibiotics (ciprofloxacin, levofloxacin, moxifloxacin, delafloxacin) that has been initiated upon, or within 24 hours of, admission to the HIM service or at time of initial Infectious Diseases consultation and lasting > 48 hours.

Arm 2:

• Previously received FQ antibiotics in the past and symptomatic.

Exclusion Criteria: 

Arm 1 - any of the following:

• FQ antibiotic treatment that has been initiated > 24 hours prior to admission that has not yet been completed (e.g., patient is admitted or transferred to HIM or had ID consult when they are already on day 3 of a 7-day course of treatment);
• Active cancer;
• Chemotherapy or radiation therapy within the past 6 months;
• Physical and/or cognitive impairment to the extent that patient cannot be fully assessed for or asked about symptoms of adverse reactions associated with fluoroquinolones;
• Currently pregnant;
• Blood transfusion within the past 4 months;
• Previous bone marrow or organ transplant;
• currently on nucleoside reverse transcriptase inhibitors;
• Pre-existing mitochondrial disease;
• < 18 years of age; 
• Prior treatment with FQs within 1 week of admission;
• Active history of routine alcohol use.

Arm 2:

• Previously received FQ antibiotics in the past and not symptomatic.

PLEASE NOTE:   At this time, only Arm 2 is open to enrollment at Mayo Clinic.

Eligibility last updated 6/2/23. Questions regarding updates should be directed to the study team contact.