What the label lists and what reports show
Moxifloxacin side effects
Moxifloxacin's FDA label: “Most common reactions (3% or greater) were nausea, diarrhea, headache, and dizziness.” FAERS holds 20,168 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 (2,203 reports).
- Generic listed
- A presentation discontinued
- Boxed warning
Check it at the source: the moxifloxacin FDA label on DailyMed (effective March 17, 2026, Macleods Pharmaceuticals Limited); 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 moxifloxacin tablets?Moxifloxacin tablets can cause side effects that may be serious or even cause death, including: See “What is the most important information I should know about moxifloxacin tablets?” Serious heart rhythm changes (QT prolongation and torsade de pointes). Tell your healthcare provider right away if you have a change in your heartbeat (a fast or irregular heartbeat), or if you faint. Moxifloxacin tablets may cause a rare heart problem known as prolongation of the QT interval. This condition can cause an abnormal heartbeat and can be very dangerous. The chances of this event are higher in people: Who are elderly With a family history of prolonged QT interval With low blood potassium (hypokalemia) Who take certain medicines to control heart rhythm (antiarrhythmics) Serious allergic reactions. […]
Source: FDA drug label, Macleods Pharmaceuticals Limited, effective March 17, 2026 (SPL set 182ecd0f-714f-42f0-9b16-fb604cf15786), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common reactions (3% or greater) were nausea, diarrhea, headache, and dizziness.
Table 2: Common (≥1%) Adverse Reactions Reported in Active-Controlled Clinical Trials with Moxifloxacin
This table is printed in the Moxifloxacin label published by Fresenius Kabi USA, LLC of May 6, 2024; the label quoted above does not print one.
| Adverse Reactions a | a MedDRA Version 12.0 % (N=14,981) |
|---|---|
| Anemia | 1.1 |
| Nausea | 6.9 |
| Pyrexia | 1.1 |
| Alanine aminotransferase increased | 1.1 |
| Hypokalemia | 1 |
| Headache | 4.2 |
| Insomnia | 1.9 |
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 reactions are discussed in greater detail in the warnings and precautions section of the label: Disabling and Potentially Irreversible Serious Adverse Reactions Including Tendinitis and Tendon Rupture, Peripheral Neuropathy, and Central Nervous System Effects [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 )] QT Prolongation [see Warnings and Precautions ( 5.6 )] Other Serious and Sometimes Fatal Adverse Reactions [see Warnings and Precautions ( 5.7 )] Risk of Aortic Aneurysm and Dissection [see Warnings and Precautions ( 5.9 )] Hypersensitivity Reactions [see Warnings and Precautions ( 5.8 )] Clostridioides difficile-Associated Diarrhea [see Warnings and Precautions ( 5.10 )] Blood Glucose Disturbances [see Warnings and Precautions ( 5.12 )] Photosensitivity/Phototoxicity [see Warnings and Precautions ( 5.13 )] Development of Drug Resistant Bacteria [see Warnings and Precautions ( 5.14 )] Most common reactions (3% or greater) were nausea, diarrhea, headache, and dizziness.
Source: FDA drug label, Macleods Pharmaceuticals Limited, effective March 17, 2026 (SPL set 182ecd0f-714f-42f0-9b16-fb604cf15786), via openFDA; the full label on DailyMed
What do FAERS reports show?
20,168 reports list moxifloxacin among the medicines taken, each a report of something that happened, not proof the medicine caused it; 2,667 are coded as a death and 6,896 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 21 reactions below, 14 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?
- Moxifloxacin: 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