Moxifloxacin (Oral)

Belonging to the class of drugs known as fluoroquinolone antibiotics, moxifloxacin fights bacterial infections which occur at various parts of the body.


Moxifloxacin is an antibiotic which is generally used only after relatively safer medications have proven unsuccessful in fighting bacterial infections which have occurred, either in the lungs, sinuses, stomach, or on the skin. The reason for this is that it is a medication which has the potential to cause some very serious side effects, and these may require additional medical treatment themselves.

While it does not work on colds or flu symptoms, moxifloxacin does kill bacteria and prevent their growth in those specific types of infections which it is well suited for. Specifically, it blocks the growth of the DNA gyrase enzyme, which is known to produce and maintain bacterial DNA, and this leads to the death of those bacteria. The kinds of bacteria that moxifloxacin will terminate include the following:

  • Moraxella catarrhalis
  • Klebsiella pneumonia
  • Haemophilus influenza
  • Escherichia coli
  • Streptococcus IQ anginosus
  • Chlamydophila pneumonia
  • Clostridium perfringens
  • Streptococcus pneumonia
  • Enterobacter cloacae
  • Streptococcus constellatus
  • Mycoplasma pneumonia

This drug comes in tablet form, and is marketed commercially under the brand name of Avelox. Because it is such a powerful drug, it comes with a Patient Information Guide, which provides instructions on its proper usage, and about some of the side effects which may be experienced by the user. It can be taken with or without food, but the dosages should always be well spaced out between times, generally in accordance with the Guide recommendations, or your doctor's specific dosing instructions.

Condition Treated

  • Bacterial infections of the skin, stomach, sinuses, and lungs.

Type Of Medicine

  • Fluroquinolone antibiotic

Side Effects

In addition to its beneficial bacteria-fighting effects, moxifloxacin also may impart some unwanted side effects to any patient using it. While in some patients, the side effects can be relatively mild and minimal in occurrence, other patients may experience severe side effects that actually call for medical attention themselves.

If you experience any of the side effects listed below to the degree that it makes you very uncomfortable, you should contact your doctor at the earliest opportunity and convey to him/her exactly what you're experiencing. After consulting with your doctor, it is possible that alternative options for treatment may be considered, or that your dosage level of moxifloxacin gets altered to become more tolerable for your body.

One of the most important potential side effects for you to be aware of is that of an allergic reaction, because of the potential for its symptoms to become life-threatening. If you suspect that you are having an allergic reaction to moxifloxacin, you should seek emergency medical attention as soon as possible, before symptoms get any worse. The symptoms to look for in an allergic reaction are the following:

  • Severe itchiness at various sites around the body
  • Extreme puffiness or swelling of the eyelids, and possibly of the tongue, lips, or throat
  • Tightening in the chest, usually accompanied by extreme difficulty with breathing
  • Hives and or rashes which appear on skin surfaces
  • Lightheadedness or dizziness, to the point where you feel like you might be about to faint.

Some other side effects which are possible after ingesting moxifloxacin are those listed below. This first grouping of side effects have only been reported rarely by patients, but are included for the sake of completeness:

  • Difficulty with swallowing
  • Difficulty with moving
  • Labored breathing
  • Diarrhea which may be severe and watery, or which may include blood
  • Dry mouth
  • Dizziness or lightheadedness when getting up quickly from a position where you were lying or sitting down
  • Blurry vision or other vision problems
  • Pain in the bones or joints
  • Clay -colored stools
  • Chills and/or fevers
  • Unexplained crying
  • Persistent coughing
  • Dark-colored urine
  • Abdominal cramps or pains
  • Stomach cramps or pains
  • Bleeding gums
  • Blisters
  • Urine which is bloody
  • The sensation of burning, numbness, or prickling at various locations around the body
  • Chest pains
  • Stools which are black and tarry
  • The feeling of bloating or fullness
  • Swelling of the lower legs, ankles, feet, hands, arms, or face
  • Muscle pains or stiffness
  • Fainting
  • Fast, pounding, or irregular heartbeat
  • Feeling of being flushed
  • Excessive muscle definition
  • Pains in the lower back, stomach, or side
  • Mood swings
  • Loss of pleasure or interest in normal things
  • Nausea and/or vomiting
  • Noisy breathing
  • Pelvic pain
  • Feeling of unreality
  • Feeling sad or empty
  • Skin which is dry or flushed
  • Breath which smells like fruit
  • Hyperventilation
  • Headaches
  • Increased sensitivity to sunlight
  • Irritability or anxiousness
  • Lack of coordination
  • Loss of appetite
  • Increased hunger or thirst
  • Pelvic pain
  • Difficulty with sleeping
  • Trouble concentrating
  • Pain experienced in the toes, legs, or fingers
  • Difficult or painful urination
  • Skin which appears pale
  • Pounding in the ears
  • Difficulty with speaking or slurred speech
  • Emotional overreactions
  • Rapid and unexplained weight gain
  • Swollen glands
  • White spots, ulcers, or sores which appear in the mouth or on the lips
  • Sore throats
  • Skin rashes and itchiness
  • Trembling or shaking of the arms, feet, legs, or hands
  • Severe sunburn
  • Redness or other discoloration which appears on the skin
  • Extreme restlessness
  • Feeling, seeing, or hearing things which no one else does
  • Sense of self-detachment from the body
  • Unexplained tiredness or drowsiness
  • Extreme breathing difficulties when any exertion is in progress
  • Tightness of the chest
  • Swelling in the facial area
  • Swelling of the lower legs, ankles, or feet
  • Profuse sweating
  • Sensational burning skin
  • Seizures and/or convulsions
  • Vomiting up blood
  • Yellowish tinge around the eyes or on the skin.

The side effects listed immediately below have been reported sporadically by patients, and are thought to be more prevalent than those listed above, but still cannot be considered as commonly occurring side effects after taking moxifloxacin.

  • Temporary stoppage of the heart
  • Unconsciousness
  • Irregular or slow heartbeat
  • Hoarseness of the voice
  • Severe tiredness
  • Persistent stomach pain
  • Unexplained change in color perception, notably with yellow or blue colors
  • General feeling of weakness or fatigue
  • Large swellings which look like hives and may appear on the legs, feet, throat, lips, tongue, sex organs, hands, eyelids, or anywhere around the face
  • Stools which are light-colored
  • Weakness of the muscles
  • Very low blood pressure as a temporary condition
  • Eyes that are red and irritated
  • Skin lesions that sometimes have a purple center and are colored red
  • Disorientation regarding place or time
  • Inability to recognize people you know
  • Hyperactivity
  • Weakness of the legs feet, hands, or arms
  • Blistering of the skin
  • Droopy eyelids
  • Pain around the eyes
  • Low pulse rate
  • Unsteadiness and difficulty with navigating.


Proper dosing of moxifloxacin will be determined by your doctor after considering several factors. Among these factors are included: your body's tolerance to the medication, the specific medical condition for which you are being treated, the strength of the medication itself, the frequency of dosing in a given day, and the total duration of time covered by your program of treatment thus far.

If you should happen to miss a dosage of moxifloxacin, it is permissible to take it as soon as you remember to do so, unless you don't remember until close to the time of your next regular dosage. In that event, it's better to skip the missed dosage entirely and just wait for the time of your next regular dosage. It is never advisable to double up on dosages just for the sake of getting back on schedule, or when you happen to feel that your symptoms are particularly severe, and you need more medication. If you suspect that you have overdosed on moxifloxacin, you should contact the Poison Control Center immediately and call your doctor.

For adults taking the oral dosage form of moxifloxacin in tablets'a standard adult dosage would be 400 mg taken once every 24 hours, although your family doctor may adjust this upward or downward depending on your symptoms and other factors. Pediatric patients must have a dosage calculated for them by the family doctor, based on age and a number of other factors.

The standard dosage described above is not meant to be considered universal for patients, and certainly not the dosage that you should take yourself. It is included only as a general reference and as a typical dosage prescribed for a large number of patients.


There are many other medications which moxifloxacin could potentially interact with, and this is a condition which should be avoided, if at all possible. When two medications interact, there is always the potential for either or both of them to lose effectiveness and not treat the condition they were intended for. It is also possible that when two drugs combine, they can impart unwanted side effects on the patient, or they can worsen any side effects which have already been occurring.

In order to prevent the possibility of drug interactions, you as a patient should prepare a list of all other medications you are currently using, including over-the-counter drugs, herbal supplements, vitamins, and any other prescription medications, as well as all of the dosages of each of these. You can provide this list to your doctor, so that he/she can review it and make a determination on whether or not there is potential for interaction with moxifloxacin.

This list can also be used if you have a need to visit any other healthcare facility where your primary care doctor is not in residence, or if you have to make an unplanned visit to an emergency room to treat a medical condition. Any doctor at one of these facilities will be able to review your medication list and prescribed treatment for your medical condition which does not conflict with your existing medications.

Some of the drugs most commonly checked for by doctors when they are looking for potential interactions are those on the list below:

  • Warfarin
  • Cholecalciferol
  • Pyroxidine
  • Ascorbic acid
  • Acetaminophen
  • Cyanocobalamin
  • Levothyroxine
  • Budesonide
  • Formoterol
  • Tiotropium
  • Prednisone
  • Fluticasone
  • Salmeterol
  • Ibuprofen
  • Aspirin
  • Amoxicillin
  • Omeprazole
  • Esomeprazole
  • Gabapentin
  • Hydrocodone
  • Ketorolac
  • Insulin gargyline
  • Furosemide
  • Omega-3 polyunsaturated fatty acids
  • Dexamethasone
  • Duloxetine
  • Ipratropium
  • Albuterol
  • Diphenhydramine
  • Clavulanate
  • Azithromycin
  • Levothyroxine.

In addition to the potential for interacting with other medications, it is also possible that moxifloxacin can interact with existing medical conditions you may have. To avoid this possibility, you should consult with your doctor about your complete medical history, so that any conditions you may have had in the past are not re-triggered, and any conditions which you have now are not worsened.

The specific medical conditions to be alert for in this regard are the following:

  • Liver diseases, including cirrhosis of the liver
  • Epileptic seizures
  • Hypoglycemia
  • Any type of organ transplant such as for the lungs, kidneys or heart
  • Tendon disorders such as rheumatoid arthritis
  • Myasthenia gravis, which is a severe weakness of the muscles
  • Hypokalemia
  • Bradycardia
  • Diabetes
  • Diarrhea
  • Heart disease
  • Prolonged QT interval
  • Hypomagnesemia
  • Hardening of the arteries
  • Kidney disease.


As with most medications, there are a number of warnings or precautions that you should be aware of when taking moxifloxacin, so as not to worsen an existing medical condition, or trigger a new one. The first thing you should be aware of as a patient, is that you need to keep all appointments with your doctor during the program of treatment with moxifloxacin. Your doctor will need each of these appointment sessions to determine how well your body is tolerating the medication, and whether there are any dangerous side effects which need to be managed. At these appointments, your doctor will also make a determination on whether or not the medication is successfully treating your condition.

If your blood has low levels of potassium, it is possible that moxifloxacin may elevate your risk of incurring an irregular heartbeat, faster or slower than normal, and that it may trigger fainting spells or a loss of consciousness after ingestion. If any of these specific symptoms occur after ingestion, you should immediately inform your doctor, so that other alternatives can be explored.

There is potential for moxifloxacin to cause diarrhea which will occasionally become very severe in nature. This condition is possible for up to two months after you stop taking moxifloxacin completely, but you should still not take any medicines, including over-the-counter drugs, which are considered treatments for diarrhea, unless you first consult with your doctor. It's possible that any diarrhea medications which you use can actually have the opposite effect, and make your condition worse, which is why you should consult with your doctor about it.

Notify your doctor immediately if you experience tingling or burning sensations in your feet, legs, hands, or arms, because these may be symptomatic of a condition known as peripheral neuropathy, and it may be that your dosage level needs to be altered.

There is a risk of inflammation of the tendons which may occur when taking moxifloxacin, or the problem could take the form of easily tearing tendons, either while you are still taking the medicine, or for a time period after that. The risk of tearing or inflamed tendons increases significantly above the age of 60, or if you are currently using medications classed as steroids, such as prednisone, prednisolone, or dexamethasone. You are also at greater risk if you have a medical history of problems with your tendons such as rheumatoid arthritis, or if you've ever had a transplanted organ. You should notify your doctor as soon as possible if you experience sudden swelling or pain in your tendons, primarily in the areas of the shoulder, wrist, elbow, ankles or in the back of your knees or legs.

If you notice that you are bruising more easily, or bleeding more profusely after an injury, you should discontinue your exercise program or exercise much more lightly, until you have a chance to consult with your doctor about the situation.

There's possibility for you to experience convulsions and seizures, extreme anxiety, confusion or disorientation, depression, difficulty with vision or hearing, severe headaches, difficulty with sleeping, or even seeing and hearing things which are not there, when you begin a treatment program with moxifloxacin. You should take note of any of these experiences which you have, as well as the date and time of them, and discuss them with your doctor at the earliest opportunity.

Some patients have reported extreme drowsiness or dizziness after taking moxifloxacin, or that they have great difficulty with focusing or concentrating after ingesting the medicine. You should be absolutely sure that you don't have any of these side effects before you attempt to operate a motor vehicle or any other kind of machinery following your dosage of moxifloxacin. You could be a danger to yourself and any other people around you if you should suddenly experience some of the symptoms without being prepared for it.

Excessive sensitivity to sunlight has been reported by a number of patients taking this medication, and for your own protection, you should take measures when out in direct sunlight to safeguard your skin from burning. In addition to sunburn, you may have greater sensitivity to skin rashes, redness, itching, or skin discoloration, all of which are triggered by hypersensitivity after taking this medication.

To avoid the potential for any of these problems you would be well advised to take the following precautions:

  • Avoid direct sunlight, especially during the peak hours when the sun is directly overhead
  • Wear a hat and sunglasses, and cover your exposed skin
  • Use sunscreen that has a rating of SPF 30 or higher, especially if you are a fair-skinned person
  • Do not use tanning beds or go to tanning salons
  • Do not use sunlamps for tanning.

A diabetic patient should be aware that moxifloxacin has the potential of impacting the level of blood sugar in your body. If you are self-monitoring and you notice changes in the level of your blood sugar or urine sugar tests, you should get in touch with your doctor as soon as possible, and discuss what you have observed.

When you are taking moxifloxacin, you should not begin taking any other drugs, even over-the-counter medications, and you should not stop taking any drugs you are currently taking, nor should you change the dosage levels of any of these medications without first consulting your doctor.


Moxifloxacin should be stored at room temperature in a location which is not subject to any extremes of heat, cold, direct lighting, or moisture, since any of these conditions will tend to degrade the medication and reduce its effectiveness. It should also never be frozen under any circumstances, since this causes even more significant degradation.

It will be important to store this medication well out of the reach of any pets in the household, or any small children who may become curious about it. For this reason, it should be stored in a high location which children cannot reach even with the assistance of furniture.

Along those same lines, moxifloxacin should not be kept in a weekly pill reminder. Even though this might be convenient for you as a patient and help to remind you about dosage days and times, these containers do not usually have locking mechanisms on them which prevent unwanted access. These can easily be opened, and any medication inside can be taken by a child in the household who is not aware of their significance.

If you have unused or expired medication, you should not simply flush it down the toilet or down the sink, where it might potentially cause harm to others. Instead, you should discard the medication according to proper disposal methods which your doctor or pharmacist can provide for you. If you lack this information, you can consult the FDA website which is maintained for this purpose, and has been constructed for the information of patients about the safe disposal of medicines.


Moxifloxacin is a medication belonging to the class of drugs known as fluoroquinolone antibiotics, and as such it is particularly effective at fighting bacterial infections which occur in the lungs or stomach, or on the skin. It is generally only used after other, safer antibiotics have been tried and found to be ineffective at treating the condition. Since this drug carries some fairly strong side effects which have been reported by some patients, it is generally not one of the first drugs tried in order to treat a patient.

Under the commercial name of Avelox, moxifloxacin is available in its oral form of dosage as a tablet, and is generally prescribed for usage in a single dosage that covers a 24-hour period. There are also a number of other medications which interact with this drug, so any patient about to be treated with this drug should make themselves aware of whether there is a possibility of conflict with a drug they might already be taking.

Moxifloxacin can cause hypersensitivity to sunlight, and can also cause powerful drowsiness after ingestion. Patients who are beginning a program of treatment with this medication should be on the alert for these and any other symptoms after the first few doses, so that the potential for dangerous situations does not arise. In the case of hypersensitivity, severe sunburns can be caused if a patient is not expecting it, and with the drowsiness side effect, you could actually fall asleep while driving or operating machinery. Before doing anything which might present a danger to yourself or to others, you should make sure you know how this medicine will affect your body, and which kinds of behaviors are likely to occur after taking moxifloxacin.