Cipro (Ciprofloxacin): Uses, dosage, side effects, warnings & patient reviews

What is Cipro (Ciprofloxacin)?

Cipro is the brand name for the antibiotic ciprofloxacin. It belongs to the fluoroquinolone class of antibiotics, which work by inhibiting bacterial DNA replication, thereby stopping the growth and spread of susceptible bacteria.

Like all antibiotics, Cipro is only effective against bacterial infections. It is not effective against viral illnesses such as the common cold, flu, or COVID-19. Misuse of antibiotics contributes to the serious global problem of antibiotic resistance.

Cipro is a potent antibiotic typically reserved for infections that are serious, difficult to treat, or caused by bacteria resistant to other antibiotic classes. It is available as oral tablets and an intravenous formulation. For more on generic alternatives, see our resource on generic medicines.

How to Take Cipro

Strict adherence to administration instructions is critical for Cipro’s effectiveness and to minimize the risk of side effects and antibiotic resistance.

Administration

Swallow cipro tablets whole with a full glass of water. It is important to drink plenty of fluids while taking this medication to prevent the formation of very concentrated urine and the associated risk of crystalluria.

Do not crush, split, or chew the tablets. If you are prescribed the oral suspension, shake the bottle well before measuring each dose with the provided measuring device.

Timing and Food

Cipro can be taken with or without food. Taking it with a meal may help reduce stomach upset. However, you must avoid taking it with dairy products (milk, yogurt) or calcium-fortified juices alone, as calcium can significantly bind to the drug and reduce its absorption. You can take Cipro with a meal that contains these items, but do not take the pill with only a glass of milk.

Additionally, avoid taking antacids, sucralfate, didanosine, or vitamin/mineral supplements containing calcium, iron, zinc, or magnesium within 2 hours before or 6 hours after taking Cipro, as they have the same binding effect.

Course Completion

It is essential to complete the entire prescribed course of antibiotics, even if you start to feel better after a few days. Stopping treatment early can lead to a resurgence of the infection and contribute to antibiotic resistance. Never save leftover medication for future use.

Side Effects of Cipro

Ciprofloxacin can cause a range of side effects, from common and mild to rare but serious. It is important for patients to be aware of all potential reactions.

What is Cipro Used For?

Ciprofloxacin is a broad-spectrum antibiotic used to treat a variety of serious bacterial infections. It is often chosen when other antibiotics are ineffective or inappropriate.

Primary Medical Uses

• Urinary Tract Infections (UTIs): Including complicated UTIs and pyelonephritis (kidney infection). For context on kidney health, see kidney disease information.
• Respiratory Tract Infections: Such as chronic bronchitis exacerbations (but not usually first-line for pneumonia).
• Skin and Soft Tissue Infections.
• Bone and Joint Infections.
• Infectious Diarrhea caused by specific bacteria.
• Prostatitis: Bacterial infection of the prostate gland.
• Typhoid Fever.

Important Limitations

Cipro is not a first-line antibiotic for common, mild infections. Its use is typically reserved for more serious cases due to its specific side effect profile. It is not effective against viral infections like the common cold or influenza.

Important Safety Concerns and Considerations

Black Box Warning: Tendon Damage

The U.S. FDA requires a “Black Box Warning”—its strongest safety alert—for fluoroquinolones like Cipro. This warning highlights the risk of tendonitis and tendon rupture, which can occur during or after treatment. The Achilles tendon is most commonly affected. This risk is higher in:

• Patients over 60 years of age.
• Those taking corticosteroid medications.
• Patients with kidney, heart, or lung transplants.
• Those with a history of tendon problems.

Patients must stop Cipro immediately at the first sign of tendon pain, swelling, or inflammation and avoid exercise of the affected area.

Peripheral Neuropathy

Cipro may cause irreversible peripheral neuropathy—nerve damage in the arms or legs. Symptoms include pain, burning, tingling, numbness, weakness, or a change in sensation. This can occur rapidly and may be permanent. If these symptoms occur, discontinue Cipro and contact your doctor immediately.

Central Nervous System Effects

Fluoroquinolones can cause central nervous system stimulation, leading to tremors, restlessness, anxiety, lightheadedness, confusion, hallucinations, paranoia, depression, nightmares, insomnia, and, rarely, seizures. Patients with a history of seizures or other CNS disorders should use Cipro with extreme caution.

QT Prolongation and Cardiac Risk

Ciprofloxacin may prolong the QT interval on an electrocardiogram, which can lead to an increased risk of an abnormal and potentially fatal heart rhythm (torsades de pointes). This risk is higher in patients with existing heart conditions, those taking other QT-prolonging drugs, and those with electrolyte imbalances (low potassium or magnesium).

Aortic Aneurysm and Dissection

Studies suggest an increased risk of aortic aneurysm (bulging) or dissection (tearing) in patients taking fluoroquinolones. The risk is highest in the elderly and those with a history of aortic aneurysm, hypertension, or certain genetic disorders (e.g., Marfan syndrome). Patients should seek immediate medical help for sudden, severe, and constant pain in the stomach, chest, or back.

Critical Warnings for Cipro Use

Absolute Contraindication with Tizanidine

Cipro is contraindicated for concurrent use with the muscle relaxant tizanidine. Cipro dramatically increases tizanidine blood levels, which can lead to severe, potentially life-threatening drops in blood pressure and extreme drowsiness.

Exacerbation of Myasthenia Gravis

Fluoroquinolones like Cipro may exacerbate muscle weakness in patients with the neurological disorder myasthenia gravis and can lead to life-threatening respiratory failure. Avoid use in patients with a known history of myasthenia gravis.

Hypersensitivity Reactions

Serious and occasionally fatal hypersensitivity (anaphylactic) reactions have been reported with Cipro, often following the first dose. Symptoms include cardiovascular collapse, loss of consciousness, tingling, pharyngeal or facial edema, dyspnea, urticaria, and itching. Discontinue the drug at the first sign of a skin rash or other allergic reaction.

Clostridioides difficile-Associated Diarrhea (CDAD)

Antibiotic use, including Cipro, can cause an overgrowth of C. difficile, resulting in diarrhea that may range from mild to life-threatening colitis. CDAD can occur even months after antibiotic treatment is completed. Report severe, persistent, or bloody diarrhea to your doctor.

Photosensitivity/Phototoxicity

As noted, Cipro can cause exaggerated sunburn reactions (photosensitivity). Patients should be advised to avoid excessive sunlight and ultraviolet (UV) light from tanning beds, and to use protective clothing and sunscreen while taking Cipro and for several days after completing therapy.

Drug Interaction with NSAIDs

Concomitant use of Cipro with nonsteroidal anti-inflammatory drugs (NSAIDs) may increase the risk of CNS stimulation and seizures. For safe use of pain relievers, see our guide on using NSAIDs smartly and safely.

Cipro Dosage Information

Dosage is determined by the treating physician based on the type and severity of infection, causative bacteria, renal function, and patient response. The following are general guidelines for adults with normal kidney function; always follow your doctor’s specific prescription.

Important Administration Notes

• Renal Impairment: Dosage reduction is required for patients with impaired kidney function (creatinine clearance less than 30-50 mL/min). Your doctor will determine the appropriate adjusted dose.
• Missed Dose: If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not take a double dose to make up for a missed one.
• Hydration: Maintain adequate hydration by drinking plenty of fluids while on this medication.

Drug Interactions with Cipro

Cipro interacts with many medications and substances, which can reduce its effectiveness, increase its side effects, or affect other drugs you are taking. Inform your doctor about all prescription and over-the-counter medications, vitamins, and herbal supplements you use.

Additional Information

Historical Fact

Ciprofloxacin was first patented in 1983 and became one of the most widely used antibiotics of the fluoroquinolone class. Its broad spectrum of activity made it effective against a wide range of bacteria. However, over time, the recognition of its serious potential side effects (leading to FDA Black Box Warnings) has led to more restrictive guidelines recommending it be reserved for infections where no safer alternative exists.

Reporting Side Effects

You are encouraged to report negative side effects of prescription drugs to the relevant national health authority (e.g., the FDA in the United States). Reporting helps health authorities monitor drug safety and identify new risks.

References and Medical Sources

The information on this page is compiled from reputable medical sources and prescribing information.

1. U.S. Food and Drug Administration (FDA). Cipro (ciprofloxacin) Prescribing Information with Boxed Warning. [Updated 2016]. https://www.accessdata.fda.gov/drugsatfda_docs/label/2016/019537s086lbl.pdf
2. MedlinePlus. Ciprofloxacin. U.S. National Library of Medicine; [Updated 2022]. https://medlineplus.gov/druginfo/meds/a688016.html
3. Drugs.com. Ciprofloxacin Professional Monograph. Drugs.com; [Updated 2024]. https://www.drugs.com/monograph/ciprofloxacin.html
4. U.S. FDA Drug Safety Communication. FDA updates warnings for fluoroquinolone antibiotics. [Updated 2018]. https://www.fda.gov/drugs/drug-safety-and-availability/fda-drug-safety-communication-fda-updates-warnings-oral-and-injectable-fluoroquinolone-antibiotics

Disclaimer: The information on this site is provided for informational purposes only and is not medical advice. It does not replace professional medical consultation, diagnosis, or treatment. Do not self-medicate based on the information presented on this site. Always consult with a doctor or other qualified healthcare professional before making any decisions about your health.