Ciprofloxacin (Cipro) is a fluoroquinolone antibiotic. It can treat many types of bacterial infections, including sinus infections and urinary tract infections (UTIs). But because ciprofloxacin (Cipro) can cause serious side effects, such as tendon rupture and nerve damage, it's usually only prescribed for more serious infections or when there aren't any safer options. Ciprofloxacin (Cipro) is taken by mouth, typically twice daily. It's available as a pill and oral solution. Some of the more common side effects of this medication include nausea and diarrhea.
Adults only
Bone and joint infections
Gonorrhea in the genitals
Long-term prostate infections
Adults and children
Ciprofloxacin (Cipro) is a fluoroquinolone (or "quinolone") antibiotic. It works by blocking certain enzymes (proteins) that bacteria use to grow and repair their genetic material (DNA) in order to survive. By blocking this process, the antibiotic kills bacteria.
Source: DailyMed
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 immediately if any of the following side effects occur:
More common
Rare
Bloody or black, tarry stools
burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
changes in skin color
changes in urination
chest pain or discomfort
chest tightness or heaviness
chills
clumsiness or unsteadiness
confusion
continuing ringing or buzzing or other unexplained noise in the ears
coughing or spitting up blood
dizziness, fainting, or lightheadedness when getting up suddenly from a lying or sitting position
fast, irregular, pounding, or racing heartbeat or pulse
headache, severe and throbbing
hearing loss
hives or welts, skin rash
joint stiffness
large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or genitals
light-colored stools
muscle pain or stiffness
nightmares
numbness of the hands
pain in the joints
pain or discomfort in the arms, jaw, back, or neck
painful, red lumps under the skin, mostly on the legs
pounding in the ears
puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
redness of the face, neck, arms, and occasionally, upper chest
seizures
severe stomach pain, cramping, or burning
shakiness in the legs, arms, hands, or feet
swelling of the face, feet, or lower legs
swollen, painful, or tender lymph glands in the neck, armpit, or groin
thick, white vaginal discharge with no odor or with a mild odor
unsteadiness, trembling, or other problems with muscle control or coordination
unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness
vomiting
white patches in the mouth or on the tongue
yellow eyes or skin
Incidence not known
Blistering, peeling, or loosening of the skin
bluish-colored lips, fingernails, or palms
bone pain
diarrhea, watery and severe, which may also be bloody
difficulty with breathing, chewing, or talking
double vision
excessive muscle tone
feeling of discomfort
feeling, seeing, or hearing things that are not there
increased sensitivity of the skin to sunlight
increased sensitivity to pain or touch
irregular or slow heart rate
loss of sense of smell
mood changes
nosebleeds
rapid heart rate
red skin lesions, often with a purple center
seeing, hearing, or feeling things that are not there
sensation of skin burning
severe sunburn
sores, ulcers, or white spots on the lips or in the mouth
uncontrolled eye movements
unusual bleeding or bruising
unusual excitement, nervousness, or restlessness
vaginal yeast infection
Some 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. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Can take with or without food
Available as tablets, oral liquid, and injection
Possible option for people with penicillin allergy
Taken twice daily
Has many potentially serious side effects and risks (e.g., nerve issues, irregular heartbeat)
Interacts with many medications, including metformin and warfarin (Coumadin)
Take ciprofloxacin (Cipro) exactly as prescribed. Make sure to finish your treatment course, even if you're feeling better. Stopping the medication earlier than prescribed can make your infection come back and become more difficult to treat.
You can take ciprofloxacin (Cipro) with or without food. If it's upsetting your stomach, try taking it with food to help. But be sure to avoid dairy products (e.g., milk, yogurt) and calcium-containing juices. Calcium can lower the amount of ciprofloxacin (Cipro) that gets absorbed into your body. Take ciprofloxacin (Cipro) at least 2 hours before or 6 hours after dairy or calcium-containing juices.
Make sure to stay well-hydrated by drinking enough fluids while taking ciprofloxacin (Cipro). Doing so helps prevent dehydration if you get diarrhea while taking ciprofloxacin (Cipro).
Ciprofloxacin (Cipro) can cause skin sensitivity to the sun. To protect your skin, make sure to wear sunscreen when going outside, wear long-sleeve clothing, and avoid being exposed to light or sun for a long time as much as possible.
If you develop watery or bloody diarrhea, fever, fatigue, or stomach cramps anytime during treatment or after stopping ciprofloxacin (Cipro), get medical help right away because these could be signs of a type of infectious diarrhea.
Limit or avoid drinking coffee or taking medications that contains caffeine, like Excedrin (acetaminophen / aspirin / caffeine) while taking ciprofloxacin (Cipro). Ciprofloxacin (Cipro) can make you more likely to feel the effects of caffeine, such as jitteriness.
If you have diabetes, ask your HCP if you need to check your blood sugar more often while taking ciprofloxacin (Cipro). This antibiotic can affect your blood sugar levels when taken with certain diabetes medications.
Speak with your healthcare team about the risks and benefits of taking ciprofloxacin (Cipro) if you're pregnant. Based on limited studies, there isn't a clear link between fluoroquinolone antibiotic use during pregnancy and harm in babies. But there's also not enough evidence to confirm that there isn't a risk to babies when taken during pregnancy.
Discuss with your healthcare team about the risks and benefits of breastfeeding while taking ciprofloxacin (Cipro). It's not recommended to breastfeed while taking ciprofloxacin (Cipro) and at least 2 days after the last dose because it can be passed into breastmilk. Consider feeding your baby with baby formula during this time.
More tips for the oral suspension (liquid)
The ciprofloxacin (Cipro) suspension is available as a 250 mg/5 mL and 500 mg/5 mL suspension. Make sure you know which strength of the suspension you have so you can measure your dose properly. Ask your pharmacist if you're not sure how much medication to measure out for your dose.
Shake the bottle well before using. Make sure to only use a medication dose cup or oral syringe from the pharmacy to measure out your dose. Don't use household spoons because they aren't accurate and might cause you to take the wrong dose.
Store the ciprofloxacin (Cipro) suspension at room temperature for up to 14 days in the original bottle you received from the pharmacy.
Ciprofloxacin (Cipro) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Age over 60 years | Taking corticosteroids | History of transplant(s) | High-intensity physical activity | Kidney failure | History of tendon-related problems, such as rheumatoid arthritis
Quinolone antibiotics like ciprofloxacin (Cipro) can raise your risk of inflammation in the tendon (tendonitis) or tearing of the tendon. This most often happens at the Achilles tendon, which is above your heel. But it can affect other tendons throughout your body too (e.g., shoulder, hand). Tendon damage can happen at any time after you start ciprofloxacin (Cipro) or up to several months after stopping the medication. If you experience pain or swelling in your joints or muscles, stop taking ciprofloxacin (Cipro) and contact your prescriber right away.
Risk factors: History of seizures or nerve damage | Medical conditions that raise the risk of seizures | Kidney problems | Taking medications that raise the risk of seizures
Fluoroquinolone antibiotics like ciprofloxacin (Cipro) can raise your risk of seizures, dizziness, and tremors. This medication can also put you at risk for nerve damage that can happen shortly after starting treatment. Nerve damage can feel like pain, numbness, tingling, burning, weakness, and changes in sensations related to touch or temperature.
Ciprofloxacin (Cipro) can also raise your risk of depression, suicidal thoughts or behavior, aggressive behavior, psychosis, nervousness, trouble sleeping, and confusion. These changes in behavior or thoughts can happen even after just one dose of medication. If you experience any of these side effects, seek medical help right away or contact your HCP. They can help manage your treatment.
If you have myasthenia gravis, taking ciprofloxacin (Cipro) can worsen symptoms like muscle weakness and difficulty breathing. Ask your prescriber about using a different antibiotic if you have myasthenia gravis.
Severe allergic reactions to ciprofloxacin (Cipro) are possible, including life-threatening reactions like facial swelling, shock, and anaphylaxis (e.g., closing of the throat). If you notice hives, rash, swelling of the lips or tongue, or difficulty breathing after taking ciprofloxacin (Cipro), get medical attention right away.
Additionally, ciprofloxacin (Cipro) can cause rare but serious skin reactions, such as Stevens-Johnson syndrome (SJS). If you notice changes in your skin, such as rash, blisters, or skin reddening or peeling, stop using ciprofloxacin (Cipro) and get medical attention as soon as possible.
Risk factors: Liver problems | Age over 55 years
Some people taking ciprofloxacin (Cipro) have had serious liver problems that can possibly lead to liver failure. Get medical attention if you notice stomach bloating or pain, yellowing of your skin or the whites of your eyes, stool changes (black, tarry, or bloody stools), or dark or brown urine. You might need to stop using the antibiotic to prevent further liver damage.
Risk factors: Age 65 years and older
In studies, there was a higher rate of severe damage to the aorta within 2 months of finishing ciprofloxacin (Cipro) treatment, especially in older adults. The aorta is the largest blood vessel in the body, and it delivers blood to the rest of your body. Damage to the aorta, such as weakening and tearing, can be severe and life-threatening. Talk with your HCP if you have a history of an aortic aneurysm since ciprofloxacin (Cipro) might not be the best medication for you. If you experience sudden pain in the chest, back, or stomach that's severe and doesn't go away, call 911 or go to the emergency room right away.
Ciprofloxacin (Cipro) can raise your risk of getting infected with a bacteria called Clostridioides difficile (C. diff). This infection can cause severe diarrhea. Antibiotics change the amount of normal bacteria in your stomach and intestines. This can cause C. diff to overgrow in your gut and lead to an infection. It's important to recognize the difference between diarrhea as a side effect of ciprofloxacin (Cipro) and this type of infectious diarrhea. C. diff-related diarrhea can cause rapid heart rate, foul-smelling diarrhea, fever, nausea, frequent bowel movements (even up to 15 times per day) and is an emergency. If you have any of these symptoms, get medical attention immediately so you can get tested for C. diff infection and receive treatment.
Risk factors: Older age | Low blood potassium or magnesium levels | History of heart problems, slow heart rate, or other abnormal heart rhythms (arrhythmias) | Personal or family history of long QT syndrome | Taking other medications that cause QT prolongation
Ciprofloxacin (Cipro) can affect your heart rhythm, which can be serious and life-threatening. One example includes lengthening the time it takes for your heart to pump and then relax. This is known as QT prolongation. Your risk for QT prolongation is higher if you have certain factors, including abnormal electrolyte levels, heart rhythm problems, or are taking other medications that cause heart rhythm problems, such as amiodarone (Pacerone), among others. If you feel your chest pounding, have shortness of breath or chest pain, or feel faint or lightheaded while taking ciprofloxacin (Cipro), call 911 right away.
In studies, some children taking ciprofloxacin (Cipro) had problems in their muscles, bones, or joints. Because of this risk, ciprofloxacin (Cipro) should only be used in children if other antibiotics can't be used. Your child's pediatrician will decide whether ciprofloxacin (Cipro) is an appropriate antibiotic for your child.
Ciprofloxacin (Cipro) makes your skin more sensitive to the sun or ultraviolet (UV) light. This means you can get sunburns more easily than usual. This can happen even during the winter and on overcast days. To lower your risk, make sure to wear sunscreen when going outside and wear long-sleeved clothing to protect your skin. Also avoid being exposed to light or sun for a long time.
Risk factors: Dehydration (low fluids in the body)
Very rarely, ciprofloxacin (Cipro) can cause kidney problems. Make sure to stay hydrated while taking this antibiotic. Let your HCP know if you have any lower back pain; difficulty urinating; or swelling in your feet, ankles, or hands. These could be signs of kidney problems caused by ciprofloxacin (Cipro).
Your healthcare team will determine your dose of ciprofloxacin (Cipro) based different factors, such as the type of infection you have and how serious it is.
General dosing for ciprofloxacin (Cipro) tablets and oral solution:
Skin, bone, and joint infections (adults): The typical dose ranges from 500 mg to 750 mg by mouth every 12 hours. Treatment for skin infections usually lasts 1 to 2 weeks. Treatment for bone and joint infections can take 1 to 2 months.
Stomach infections and infectious diarrhea (adults): The typical dose is 500 mg by mouth every 12 hours. Treatment for serious stomach infections usually last 1 to 2 weeks. Treatment for infectious diarrhea can take 5 to 7 days.
Sinus infections and typhoid fever (adults): The typical dose is 500 mg by mouth every 12 hours for 10 days.
Lower respiratory tract infection (adults): The typical dose ranges from 500 mg to 750 mg by mouth every 12 hours for 1 to 2 weeks.
Prostate infections (adults): The typical dose is 500 mg by mouth every 12 hours for a month.
Gonorrhea (adults): The typical dose is 250 mg by mouth as a single dose.
Urinary tract infections
Adults: The typical dose is 250 mg by mouth every 12 hours for 3 days. The dosing for more serious infections ranges from 250 mg to 500 mg by mouth every 12 hours for 1 to 2 weeks.
Children (ages 1 year and older): Your child's pediatrician will determine the dose based on your child's body weight. The typical dose ranges from 10 mg/kg to 20 mg/kg (maximum 750 mg) by mouth every 12 hours for 10 to 21 days.
Anthrax
Adults: The typical dose is 500 mg by mouth every 12 hours for 2 months.
Children: Your child's pediatrician will determine the dose based on your child's body weight. The typical dose is 15 mg/kg (maximum 500 mg) by mouth every 12 hours for 2 months.
Plague
Adults: The typical dose is 500 mg to 750 mg by mouth every 12 hours for 2 weeks.
Children: Your child's pediatrician will determine the dose based on your child's body weight. The typical dose is 15 mg/kg (maximum 500 mg) by mouth every 8 to 12 hours for 2 weeks.
Your dose might differ if you have kidney or liver problems.
Ciprofloxacin (Cipro) is also available as an injection through the veins that's given by a healthcare professional in the hospital setting.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Severe allergy to a quinolone antibiotic
Taking tizanidine (Zanaflex) with ciprofloxacin (Cipro)
Adults only
Bone and joint infections
Gonorrhea in the genitals
Long-term prostate infections
Adults and children
Sudden worsening of chronic (long-term) bronchitis
Long-term prostate infections
Lung infections (e.g., community acquired pneumonia, chronic bronchitis flare-ups)
Skin infections
Gut infections
Sinus infections
By signing up, I agree to GoodRx's Terms and Privacy Policy, and to receive marketing messages from GoodRx.
Al-Khatib, S. M., et al. (2003). What clinicians should know about the QT interval. Journal of the American Medical Association.
American Heart Association. (2021). Your aorta: The pulse of life.
Centers for Disease Control and Prevention. (2020). Spoons are for Soup, Milliliters are for Medicine.
Centers for Disease Control and Prevention. (2022). Typhoid fever.
Centers for Disease Control and Prevention. (2020). Types of anthrax.
Chartwell RX, LLC. (2023). CIPROFLOXACIN kit [package insert]. DailyMed.
Food and Drug Administration. (2018). FDA Drug Safety Communication: FDA advises restricting fluoroquinolone antibiotic use for certain uncomplicated infections; warns about disabling side effects that can occur together.
Food and Drug Administration. (2017). Ciprofloxacin use by pregnant and lactating women.
Hikma Pharmaceuticals USA Inc. (2023). CIPROFLOXACIN tablet, film coated. DailyMed.
Hospira, Inc. (2023). CIPROFLOXACIN IN DEXTROSE- ciprofloxacin injection, solution. DailyMed.
Pandey, N., et al. (2022). Beta lactam antibiotics. StatPearls.
Singh, D. (2015). Acute Achilles tendon rupture. British Medical Journal.
Wanleenuwat, P., et al. (2020). Antibiotic-induced epileptic seizures: mechanisms of action and clinical considerations. Seizures.
Yefet, E., et al. (2018). The safety of quinolones and fluoroquinolones in pregnancy: A meta-analysis. BJOG : An International Journal of Obstetrics and Gynaecology.
Research prescriptions and over-the-counter medications from A to Z, compare drug prices, and start saving.