In the U.S.—

• Antibacterial, systemic

Cinoxacin (sin-OX-a-sin) is used to prevent and treat infections of the urinary tract. It will not work for other infections or for colds, flu, or other virus infections.

Cinoxacin is available only with your doctor's prescription, in the following dosage form:

Oral
• Capsules (U.S.)

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For cinoxacin, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to cinoxacin or to any related medicines such as ciprofloxacin (e.g., Cipro), enoxacin (e.g., Penetrex), lomefloxacin (e.g., Maxaquin), nalidixic acid (e.g., NegGram), norfloxacin (e.g., Noroxin), or ofloxacin (e.g., Floxin). Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Studies have not been done in humans. However, use is not recommended during pregnancy since cinoxacin has been shown to cause bone development problems in young animals.

Breast-feeding—It is not known whether cinoxacin passes into the breast milk. However, other related medicines do pass into the breast milk. Since cinoxacin has been shown to cause bone development problems in young animals, use is not recommended in nursing mothers.

Children—Since this medicine has been shown to cause bone development problems in young animals, its use is not recommended in children up to 18 years of age.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults. Although there is no specific information comparing use of cinoxacin in the elderly with use in other age groups, this medicine is not expected to cause different side effects or problems in older people than it does in younger adults.

• Brain and spinal cord disorders
• Convulsions
• Tendinitis—Cinoxacin may make these conditions worse

• Kidney disease—Patients with kidney disease may have an increased risk of side effects

Cinoxacin may be taken with food, unless you are otherwise directed by your doctor.

Do not give this medicine to infants or children under 18 years of age, unless otherwise directed by your doctor. It has been shown to cause bone development problems in young animals.

To help clear up your infection completely, keep taking this medicine for the full time of treatment, even if you begin to feel better after a few days. If you stop taking this medicine too soon, your symptoms may return.

This medicine works best when there is a constant amount in the urine. To help keep the amount constant, do not miss any doses. Also, it is best to take the doses at evenly spaced times, day and night. For example, if you are to take 4 doses a day, the doses should be spaced about 6 hours apart. If this interferes with your sleep or other daily activities, or if you need help in planning the best times to take your medicine, check with your health care professional.

Dosing—

The dose of cinoxacin will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of cinoxacin. Your dose may be different if you have kidney disease. If your dose is different, do not change it unless your doctor tells you to do so.

The number of capsules that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on whether you are using cinoxacin to prevent or to treat urinary tract infections .

• For capsule dosage form:
  • For the prevention of urinary tract infections:
    • Adults—250 milligrams (mg) at bedtime for up to five months.
    • Children up to 18 years of age—Use is generally not recommended because it may cause bone development problems.
  • For the treatment of urinary tract infections:
    • Adults—250 mg every six hours; or 500 mg every twelve hours for seven to fourteen days.
    • Children up to 18 years of age—Use is generally not recommended because it may cause bone development problems.

Missed dose—

If you miss a dose of this medicine, take it as soon as possible. This will help to keep a constant amount of medicine in the urine. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

If your symptoms do not improve within a few days, or if they become worse, check with your doctor.

This medicine may also cause some people to become dizzy. 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. If this reaction is especially bothersome, check with your doctor.

Some people who take cinoxacin may become more sensitive to sunlight than they are normally. Exposure to sunlight, even for brief periods of time, may cause severe sunburn; skin rash, redness, itching, or discoloration; or vision changes. When you begin taking this medicine:

• Stay out of direct sunlight, especially between the hours of 10:00 a.m. and 3:00 p.m., if possible.
• Wear protective clothing, including a hat and sunglasses.
• Apply a sun block product that has a skin 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 health care professional.
• Do not use a sunlamp or tanning bed or booth.

If you have a severe reaction from the sun, check with your doctor.

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 as soon as possible if any of the following side effects occur:

• Less common
  • Skin rash, itching, redness, or swelling 
  
  

• Rare
  • black, tarry stools;  bleeding gums;  blood in urine or stools;  Dizziness ;  headache;  increased sensitivity of skin to sunlight;  pinpoint red spots on skin;  unusual bleeding or bruising 
  
  

• Incidence unknown
  • Bone pain;  lower back or side pain;  pain, inflammation, or swelling in calves, shoulders, or hands ;  painful, swollen joints;  seizures 
  
  

Other 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. However, check with your doctor if any of the following side effects continue or are bothersome:

• Less common
  • Diarrhea;  loss of appetite;  nausea;  stomach cramps;  vomiting 
  
  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.