If your symptoms do not improve within a few days, or if they become worse, check with your doctor.
This medicine may cause serious allergic reactions, including anaphylaxis, which can be life-threatening and require immediate medical attention. Call your doctor right away if you have a rash, itching, hives, hoarseness, lightheadedness or fainting, shortness of breath, trouble with breathing, trouble with swallowing, or any swelling of your hands, face, or mouth after you take this medicine.
Serious skin reactions can occur with this medicine. Stop using this medicine and check with your doctor right away if you have blistering, peeling, or loosening of the skin, red skin lesions, severe acne or skin rash, sores or ulcers on the skin, or fever or chills while you are using this medicine.
Levofloxacin may cause serious liver problems, including hepatitis. Stop taking this medicine and check with your doctor right away if you start having nausea or vomiting, dark urine, light-colored stools, stomach pain, or yellow eyes or skin while you are using this medicine.
Levofloxacin may cause diarrhea, and in some cases it can be severe. It may occur 2 months or more after you stop using this medicine. Do not take any medicine to treat diarrhea without first checking with your doctor. Diarrhea medicines may make the diarrhea worse or make it last longer. If you have any questions about this or if mild diarrhea continues or gets worse, check with your doctor.
Stop using this medicine and tell your doctor right away if you start having numbness, tingling, or burning pain in your hands, arms, legs, or feet. These may be symptoms of a condition called peripheral neuropathy.
For patients with low potassium levels or an abnormally slow heartbeat: Levofloxacin may increase your risk of having a fast, slow, or irregular heartbeat. Call your doctor right away if you feel that your heart is not beating normally.
Some people who take levofloxacin may become more sensitive to sunlight than they are normally. Exposure to sunlight, even for brief periods of time, may cause severe sunburn or skin rash, redness, itching, or discoloration. When you begin taking this medicine:
- Stay out of direct sunlight, especially between the hours of 10 AM and 3 PM, if possible.
- Wear protective clothing, including a hat and sunglasses.
- Apply a sun block product that has a sun protection factor (SPF) of at least 15. Some patients may require a product with a higher SPF number, especially if they have a fair complexion. If you have any questions about this, check with your doctor.
- Do not use a sun lamp or tanning bed or booth.
If you have a severe reaction from the sun, check with your doctor.
Levofloxacin may cause some people to become dizzy, lightheaded, drowsy, or less alert than they are normally. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy or are not alert. If these reactions are especially bothersome, check with your doctor.
Levofloxacin may rarely cause inflammation or even tearing of a tendon (the cord that attaches muscles to the bones). The risk of having tendon problems may be increased if you are over 60 years of age, using steroid medicines (e.g., dexamethasone, prednisolone, prednisone, or Medrol®), have severe kidney problems, have a history of tendon problems (e.g., rheumatoid arthritis), or have received an organ (e.g., heart, kidney, or lung) transplant. If you get sudden pain or swelling in a tendon after exercise (e.g., in the ankle, back of the knee or leg, shoulder, elbow, or wrist), stop using this medicine and check with your doctor right away. Refrain from exercise until your doctor says otherwise.
For diabetic patients taking insulin or diabetes medicine by mouth: Levofloxacin may cause hypoglycemia (low blood sugar) in some patients. Symptoms of low blood sugar must be treated before they lead to unconsciousness (passing out). Different people may feel different symptoms of low blood sugar. If you experience symptoms of low blood sugar, stop taking levofloxacin and check with your doctor right away:
- Symptoms of low blood sugar can include: Anxious feeling, behavior change similar to being drunk, blurred vision, cold sweats, confusion, cool pale skin, difficulty with concentrating, drowsiness, excessive hunger, headache, nausea, nervousness, rapid heartbeat, shakiness, or unusual tiredness or weakness.
Before you have any medical tests, tell the medical doctor in charge that you are using this medicine. The results of some tests may be affected by this medicine.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.