The dosage depends largely on the type and severity of the infection being treated. The usual adult dose for respiratory tract infections is 500 mg twice a day.

Ciprofloxacin is an antibiotic medication that kills various bacteria. It works by inhibiting the synthesis of bacterial DNA which results in bacterial cell death. The effectiveness of ciprofloxacin depends on factors such as dose, concentration in the blood, body fluids and tissues, and the susceptibility of the bacteria. Ciprofloxacin does not kill all types of bacteria, but only those that have a sensitivity to this antibiotic. Infections caused by bacteria that are not sensitive to ciprofloxacin will not show improvement after taking this medication.

Along with its needed effects, ciprofloxacin may cause some unwanted or undesirable effects. Generally, ciprofloxacin is well tolerated and many people will not experience unwanted effects. The frequency and severity of these effects is dependant on many factors including dose, duration of therapy and individual susceptibility. Possible unwanted effects include:

• diarrhea
• nausea
• stomach discomfort

Uncommon:

• vomiting
• headache
• dizziness
• sleep disorder
• agitation
• tremors
• seizures
• shortness of breath
• confusion

Rare:

• rash
• pseudomembranous colitis (inflammation of the colon caused by the overgrowth and toxin production of bacteria that are not killed by the antibiotic)
• depression

Use as directed. Many antacids and multivitamins may interfere with the absorption of ciprofloxacin. You should take ciprofloxacin either two hours before or six hours after taking these products.
Allergic reactions can occur with ciprofloxacin use. The reaction can be immediate and severe. Allergic symptoms include wheezing, hives, itching, swelling, joint and muscle pain, difficulty breathing, fever and skin rashes. Nausea and vomiting are not symptoms of an allergic reaction.
Taking the antibiotic repeatedly or for prolonged periods may result in bacterial or fungal overgrowth which can lead to a second infection. When this occurs, the ciprofloxacin may need to be stopped and another antibiotic prescribed to treat the new infection.
Diarrhea often develops while taking ciprofloxacin. This is sometimes caused by an overgrowth of bacteria in the gut that are not killed by the antibiotic. In severe cases, this may be life threatening and would require treatment with other antibiotics. In mild cases, symptoms disappear shortly after the drug is discontinued.
If you experience joint or muscle pain while taking ciprofloxacin, notify your doctor, rest and do not exercise. There are some reports of tendon tears occurring during treatment with ciprofloxacin.

Ciprofloxacin can increase sensitivity to the sun. Avoid exposure to excessive sunlight, including sunlamps and tanning beds. If you must spend time in the sun use sunblock with minimum SPF 15.

Drug Interactions: It is important to tell your doctor and pharmacist of any prescription or over-the-counter medications you are taking. In some cases, the dose of one or both drugs may need to be altered or another drug may be prescribed.
The following drugs or drug classes have been known to interact with ciprofloxacin:

• antacids that contain aluminum or magnesium
• probenecid (e.g. Benemid®)
• iron or mineral supplements
• zinc-containing products
• warfarin (e.g. Coumadin®)
• hydantoins (e.g. Dilantin®)
• hypoglycemic drugs (e.g. glyburide)
• cyclosporine (e.g. Neoral®)
• sucralfate (e.g. Sulcrate®)
• theophylline (e.g. Theo-Dur®)

Use is not recommended in the following situations:

• allergy to ciprofloxacin or any quinolone (e.g. norfloxacin, ofloxacin)

Caution is recommended in the following situations:

• kidney disease
• nervous system disorders (e.g. epilepsy)
• liver disease

Use in pregnancy: Consult your doctor or pharmacist if you suspect you are pregnant.
Use while breastfeeding: Ciprofloxacin does appear in breast-milk. Use during breastfeeding is not recommended. Consult your doctor or pharmacist if you have any questions.