Moxifloxacin (Avelox) is a fluoroquinolone antibiotic. It can treat different types of infections, including certain skin infections and lung infections, in adults. But because moxifloxacin (Avelox) can cause serious side effects, such as tendon rupture and nerve damage, it's usually only prescribed for more serious infections or when safer options aren't available. Moxifloxacin (Avelox) is taken by mouth, typically once daily. Some of the more common side effects of this medication include nausea, diarrhea, and headache. Moxifloxacin is generic only, brand-name Avelox is no longer available.
Treatment of certain bacterial infections, including:
Lung infections (e.g., community acquired pneumonia, chronic bronchitis flare-ups)
Skin infections
Gut infections
Sinus infections
Moxifloxacin (Avelox) is a fluoroquinolone (or "quinolone") antibiotic. It works by blocking certain enzymes (proteins) that bacteria use to grow and repair their genetic material in order to survive. By blocking this process, the antibiotic kills bacteria.
Source:Â DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Incidence not known
Fainting or loss of consciousness
fast or irregular breathing
itching or skin rash
swelling of the eyes or eyelids
tightness in the chest
trouble with breathing
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Burning, dry, or itching eyes
change in vision
decreased vision
excessive tearing
eye discharge
itching of the eye
pain in the eye
red, sore eyes
tearing
Less common
Body aches or pain
congestion
cough or hoarseness
decreased hearing
dryness or soreness of the throat
fever or chills
general body discomfort
lower back or side pain
painful or difficult urination
rubbing or pulling of the ears (in children)
tender, swollen glands in the neck
trouble with swallowing
voice changes
vomiting and diarrhea (in infants)
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Can take with or without food
Only taken once a day
Treats many types of infections
Might be an option for people who have penicillin allergy
Not well-studied in children
Interacts with a lot of common medications, such as warfarin (Coumadin) and antacids
Has many potentially serious side effects and risks (e.g., nerve issues, irregular heartbeat)
Take moxifloxacin (Avelox) at least 4 hours before or 8 hours after any antacids for heartburn (e.g., Tums) and supplements containing magnesium, aluminum, iron, or zinc. These medications can interfere with how your body absorbs moxifloxacin (Avelox) and cause it to not work as well at treating infections.
Your prescriber will give you moxifloxacin (Avelox) for the shortest amount of time necessary to treat your infection. If you take moxifloxacin (Avelox) for too long, it can cause new fungal or bacterial infections to develop that might be harder to treat. Let your healthcare professional (HCP) know if you notice symptoms of a new infection or if the original symptoms don't get better after you've finished your entire course of moxifloxacin (Avelox).
If you experience tendon pain, swelling, or inflammation, stop taking moxifloxacin (Avelox) right away and let your HCP know. These might be symptoms of a more serious fluoroquinolone side effect.
Tell your HCP immediately if you experience symptoms of seizure, depression, or changes in mood while taking moxifloxacin (Avelox).
Moxifloxacin (Avelox) can cause you to feel dizzy and lightheaded. Avoid driving or do activities that require a lot of focus until you know how this medication affects you.
Moxifloxacin (Avelox) can cause skin sensitivity to the sun. To protect your skin, make sure to wear sunscreen when going outside, wear long-sleeved clothing, and avoid being exposed to light or sun for a long time as much as possible.
If you have diabetes, ask your prescriber if you need to check your blood sugar more often while taking moxifloxacin (Avelox). This antibiotic can affect your blood sugar levels when taken with certain diabetes medications.
Avoid taking non-steroidal anti-inflammatory drugs (NSAIDs) medications (e.g., ibuprofen (Advil), naproxen (Aleve)) while taking moxifloxacin (Avelox). Taking NSAIDs can raise your risk of nerve-related side effects and seizures from moxifloxacin (Avelox). Keep in mind that NSAIDs are in many over-the-counter (OTC) products. If you take NSAIDs on a regular basis, let your prescriber know before starting this antibiotic.
Moxifloxacin (Avelox) can interact with many medications, such as those that affect heart rhythm. Let your HCP or pharmacist know what medications you're taking, including OTC products and supplements, before you start moxifloxacin (Avelox). Talk with your prescriber or pharmacist if you have any questions about interactions with this medication.
Moxifloxacin (Avelox) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Age over 60 years | Taking corticosteroids | History of transplant(s) | High-intensity exercise | Kidney failure | History of tendon-related problems, such as rheumatoid arthritis
Quinolone antibiotics like moxifloxacin (Avelox) can raise your risk of inflammation in the tendon (tendonitis) or tearing of the tendon. This most often happens at the Achilles tendon, which is above your heel. But it can affect other tendons throughout your body too (e.g., shoulder, hand). Tendon damage can happen at any time after you start moxifloxacin (Avelox) or up to several months after stopping the medication. If you experience pain or swelling in your joints or muscles, stop taking moxifloxacin (Avelox) and contact your healthcare professional (HCP) right away.
Risk factors: History of seizures or nerve damage | Medical conditions that raise the risk of seizures | Taking medications that raise the risk of seizures
Fluoroquinolone antibiotics like moxifloxacin (Avelox) can raise your risk of seizures, dizziness, and tremors. This medication can also put you at risk for nerve damage that can happen shortly after starting treatment. Nerve damage can feel like pain, numbness, tingling, burning, weakness, and changes in sensations related to touch or temperature.
In addition, moxifloxacin (Avelox) can also raise your risk of depression, suicidal thoughts or behavior, aggressive behavior, psychosis, nervousness, trouble sleeping, and confusion. These changes in behavior or thoughts can happen even after just one dose of medication. If you experience any of these side effects, get medical help right away or contact your prescriber. They can help manage your treatment.
If you have myasthenia gravis, taking antibiotics similar to moxifloxacin (Avelox) can worsen symptoms like muscle weakness. In rare cases, it can lead to difficulty breathing. Ask your prescriber about using a different antibiotic if you have myasthenia gravis.
Risk factors: Older people | Low blood potassium or magnesium levels | History of heart problems, slow heart rate, or other abnormal heart rhythms (arrhythmias) | Personal or family history of long QT syndrome | Taking other medications that cause QT prolongation | History of liver problems
Moxifloxacin (Avelox) can affect your heart rhythm, which can be serious and life-threatening. One example includes lengthening the time it takes for your heart to pump and then relax. This is known as QT prolongation. Your risk for QT prolongation is higher if you have certain factors, including abnormal electrolyte levels, heart rhythm problems, or are taking other medications that cause heart rhythm problems, such as amiodarone (Pacerone), among others. If you feel your chest pounding, have trouble breathing or chest pain, or feel faint or lightheaded while taking moxifloxacin (Avelox), call 911 right away.
Severe allergic reactions to moxifloxacin (Avelox) are possible, including life-threatening reactions like passing out, facial swelling, and anaphylaxis (e.g., closing of the throat). If you notice hives, rash, swelling of the lips or tongue, or difficulty breathing after taking moxifloxacin (Avelox), get medical attention right away.
Moxifloxacin (Avelox) can also cause rare but serious skin reactions, such as Stevens-Johnson syndrome (SJS). If you notice changes in your skin, such as rash, blisters, or skin reddening or peeling, stop using moxifloxacin (Avelox) and get medical attention as soon as possible.
In addition, people who took fluoroquinolone antibiotics also reported other serious reactions that affect different areas of the body, including lungs, liver, and kidneys. Let your healthcare team know right away if you don't feel well or notice yellowing of the skin or whites of the eyes after you start moxifloxacin (Avelox).
Risk factor: Older adults
In studies, there was a higher rate of severe damage to the aorta within 2 months of finishing moxifloxacin (Avelox) treatment, especially in older adults. The aorta is the largest blood vessel in the body, and it delivers blood to the rest of your body. Damage to the aorta, such as weakening and tearing, can be severe and life-threatening. Talk with your prescriber if you've a history of an aortic aneurysm since moxifloxacin (Avelox) might not be the best medication for you. If you experience sudden pain in the chest, back, or stomach that's severe and doesn't go away, call 911 or go to the emergency room right away.
Antibiotics, such as moxifloxacin (Avelox), can raise the risk of getting a bacterial infection called Clostridioides difficile (C. diff). This infection can cause severe diarrhea that can happen up to 2 months after your last dose of your antibiotic treatment. To lower your risk of C. diff-related diarrhea, your HCP will prescribe the lowest dose of moxifloxacin (Avelox) for the shortest amount of time that will treat your infection. If you experience severe or watery diarrhea, bloody stools, fever, belly pain, loss of appetite, or nausea, let your prescriber know right away.
Risk factor: Diabetes
Taking moxifloxacin (Avelox) can change your blood sugar levels, which can potentially worsen your diabetes. In some cases, your HCP will need to adjust your dose of diabetic medications to make sure your blood sugar is under control. If you have a history of diabetes, let your prescriber know before starting moxifloxacin (Avelox). Your HCP might ask you to check your blood sugar at home to make sure this medication is safe for you. If you've symptoms of low blood sugar such as feeling shaky, confused, or very hungry; being nervous or anxious; having a fast heartbeat; sweating; or having body chills, bring your sugar level back up quickly with fast-acting sugar (e.g., 4 glucose tablets, 1/2 cup of fruit juice). Stop taking moxifloxacin (Avelox) right away and let your HCP know if this happens.
Moxifloxacin (Avelox) makes your skin more sensitive to the sun and ultraviolet (UV) light. This means you can get sunburns more easily than usual. This can happen even during the winter and on overcast days. To lower your risk, make sure to wear sunscreen when going outside and wear long-sleeved clothing to protect your skin. Also, avoid being exposed to the sun for a long time.
Pneumonia: The typical dose is 400 mg by mouth once daily for 1 to 2 weeks.
Skin infections: The typical dose is 400 mg by mouth once daily for 1 to 3 weeks, depending on how serious your infection is.
Stomach infections: The typical dose is 400 mg by mouth once daily for 5 days to 2 weeks, depending on how serious your infection is.
Plague: The typical dose is 400 mg by mouth once daily for 10 to 14 days.
Sinus infections: The typical dose is 400 mg by mouth once daily for 10 days.
Sudden worsening of chronic bronchitis: The typical dose is 400 mg by mouth once daily for 5 days.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Allergy to other fluoroquinolones
Treatment of certain bacterial infections, including:
Lung infections (e.g., community acquired pneumonia, chronic bronchitis flare-ups)
Skin infections
Gut infections
Sinus infections
Sudden worsening of chronic (long-term) bronchitis
Long-term prostate infections
Bone and joint infections
Gonorrhea in the genitals
Long-term prostate infections
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Randel, A. (2013). IDSA updates guideline for managing group A streptococcal pharyngitis. American Family Physician.
Singh, D. (2015). Acute achilles tendon rupture. The British Medical Journal.
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