What the label lists and what reports show
Levofloxacin side effects
Levofloxacin's FDA label: “The most common reactions ( > 3%) were nausea, headache, diarrhea, insomnia, constipation and dizziness ( 6.1 ).” FAERS holds 59,954 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is dyspnoea (3,047 reports).
- Generic listed
- Boxed warning
Check it at the source: the levofloxacin FDA label on DailyMed (effective July 10, 2024, Lupin Pharmaceuticals, Inc.); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of levofloxacin tablets?Levofloxacin tablets may cause serious side effects, including: See "What is the most important information I should know about levofloxacin tablets?" Serious allergic reactions. Allergic reactions can happen in people taking fluoroquinolones, including levofloxacin, even after only 1 dose. Stop taking levofloxacin tablets and get emergency medical help right away if you have any of the following symptoms of a severe allergic reaction: hives trouble breathing or swallowing swelling of the lips, tongue, face throat tightness, hoarseness rapid heartbeat faint skin rash Skin rash may happen in people taking levofloxacin tablets, even after only 1 dose. Stop taking levofloxacin tablets at the first sign of a skin rash and immediately call your healthcare provider. Skin rash may be a sign of a more serious reaction to levofloxacin. […]
Source: FDA drug label, Lupin Pharmaceuticals, Inc., effective July 10, 2024 (SPL set 4be13bd5-0c39-43c3-9232-b1226ccd4dbc), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsThe most common reactions ( > 3%) were nausea, headache, diarrhea, insomnia, constipation and dizziness ( 6.1 ).
A table the label prints in its adverse reactions section without a title; its column headings name the groups compared
This table is printed in the Levofloxacin label published by Chartwell RX, LLC of June 29, 2026; the label quoted above does not print one.
| Adverse Reaction | % (N=7537) |
|---|---|
| moniliasis | 1 |
| insomnia | 4 |
| headache | 6 |
| dizziness | 3 |
| dyspnea | 1 |
| nausea | 7 |
| diarrhea | 5 |
| constipation | 3 |
| abdominal pain | 2 |
| vomiting | 2 |
| dyspepsia | 2 |
| rash | 2 |
| pruritus | 1 |
| edema | 1 |
| injection site reaction | 1 |
| chest pain | 1 |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe following serious and otherwise important adverse drug reactions are discussed in greater detail in other sections of labeling: Disabling and Potentially Irreversible Serious Adverse Reactions [see Warnings and Precautions ( 5.1 )] Tendinitis and Tendon Rupture [see Warnings and Precautions ( 5.2 )] Peripheral Neuropathy [see Warnings and Precautions ( 5.3 )] Central Nervous System Effects [see Warnings and Precautions ( 5.4 )] Exacerbation of Myasthenia Gravis [see Warnings and Precautions ( 5.5 )] Other Serious and Sometimes Fatal Reactions [see Warnings and Precautions ( 5.6 )] Hypersensitivity Reactions [see Warnings and Precautions ( 5.7 )] Hepatotoxicity [see Warnings and Precautions ( 5.8 )] Risk of Aortic Aneurysm and Dissection [see Warnings and Precautions ( 5.9 )] Clostridium difficile -Associated Diarrhea [see Warnings and Precautions ( 5.10 )] Prolongation of the QT Interval [see Warnings and Precautions ( 5.11 )] Musculoskeletal Disorders in Pediatric Patients [see Warnings and Precautions ( 5.12 )] Blood Glucose Disturbances [see Warnings and Precautions ( 5.13 )] Photosensitivity/Phototoxicity [see Warnings and Precautions ( 5.14 )] Development of Drug Resistant Bacteria [see Warnings and Precautions ( 5.15 )] Crystalluria and cylindruria have been reported with quinolones, including levofloxacin. …
Source: FDA drug label, Lupin Pharmaceuticals, Inc., effective July 10, 2024 (SPL set 4be13bd5-0c39-43c3-9232-b1226ccd4dbc), via openFDA; the full label on DailyMed
What do FAERS reports show?
59,954 reports list levofloxacin among the medicines taken, each a report of something that happened, not proof the medicine caused it; 8,134 are coded as a death and 27,956 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 19 reactions below, 12 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Levofloxacin: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions