Cipro (ciprofloxacin) is a brand-name prescription medication. The Food and Drug Administration (FDA) has approved it to treat infections caused by certain bacteria. Specifically, Cipro may be used to treat the following infections in certain people:

Here are some fast facts about Cipro:

  • Active ingredient: ciprofloxacin
  • Drug class: fluoroquinolone antibiotic
  • Drug form: oral tablet or liquid suspension

Cipro is currently only available as a tablet or powder for liquid suspension. However, ciprofloxacin (the active drug in Cipro) is also available in other forms, including an injectable form and an eye drop. Ciprofloxacin is also available in combination with another drug, dexamethasone, which comes as an ear drop. However, this article will focus on the brand-name forms of Cipro.

Cipro is an antibiotic, so your doctor will likely recommend taking it short term to treat a bacterial infection.

As with other drugs, Cipro can cause side effects (adverse effects). Read on to learn about potential common, mild, and serious side effects. For a general overview of Cipro, including details about its uses, see this article.

Cipro can cause certain side effects, some of which are more common than others. These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

These are just a few of the more common side effects reported by people who took Cipro in clinical trials:

  • liver problems
  • vomiting
  • skin rash
  • diarrhea*
  • nausea*

* For more information about this side effect, see “Side effect specifics” below.

Mild side effects can occur with Cipro use. This list doesn’t include all possible mild side effects of the drug. For more information, you can refer to Cipro’s prescribing information.

Mild side effects that have been reported with Cipro include:

These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks side effects of the medication. If you develop a side effect while taking Cipro and want to tell the FDA about it, visit MedWatch.

* For more information about this side effect, see “Side effect specifics” below.

Cipro may cause serious side effects. The list below may not include all possible serious side effects of the drug. For more information, you can refer to Cipro’s prescribing information.

If you develop serious side effects while taking Cipro, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Serious side effects that have been reported and their symptoms include:

* For more information about this side effect, see “Side effect specifics” below.
Cipro has a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA). To learn more, see the “Side effect specifics” section below.

In some cases, doctors may prescribe Cipro to treat certain infections in children. Examples of these may include complicated urinary tract infections (UTIs) or treatment of the plague.

Children taking Cipro have a higher risk of bone, joint, or tendon problems occurring. These can include pain or swelling of a bone, joint, or tendon. Because of this risk, doctors will typically only recommend Cipro for use in children if there isn’t a safer choice for treating their infection.

If you have questions or concerns about side effects that your child may experience from Cipro, talk with their doctor.

Cipro may cause several side effects. Here are some frequently asked questions about the drug’s side effects and their answers.

Does Cipro cause different side effects in older adults?

It’s possible for older adults (ages 65 years and over) to be at an increased risk of side effects compared with younger people taking Cipro.

Older adults may be at an increased risk of serious side effects, such as tendon rupture. Tendon rupture can even occur months after taking Cipro. You may be at a higher risk of this side effect occurring if you’re also taking a corticosteroid drug, such as Rayos (prednisone). Before you start Cipro, be sure to talk with your doctor about your risk of tendon rupture. Also, make sure you tell them about any other medications that you’re taking.

In addition, it’s possible for Cipro to increase the risk of heart problems occurring in older adults. This may include a serious side effect called an aortic aneurysm or aortic dissection. This side effect wasn’t seen in younger people taking the drug.

If you’re an older adult taking Cipro, you should be aware of the possible symptoms of these conditions so that you can go to the hospital right away. Symptoms may include:

  • chest pain
  • loss of consciousness
  • difficulty breathing
  • abdominal pain

Older adults may also be at an increased risk of other heart-related side effects, such as long QT syndrome.

If you are an older adult taking Cipro, talk with your doctor or pharmacist if you’re concerned about side effects from the drug.

Can Cipro cause constipation as a side effect?

You shouldn’t experience constipation from taking Cipro. This wasn’t a side effect that people reported in clinical trials. In fact, Cipro commonly causes diarrhea.

If you experience constipation during your treatment with Cipro, talk with your doctor. They can help determine what may be causing your constipation to occur and the best way to treat it. In some cases, they may be able to recommend an over-the-counter treatment, such as MiraLAX (polyethylene glycol).

Are the side effects of Flagyl and Cipro the same?

No, the side effects of Cipro and Flagyl are not the same. However, both medications may cause similar side effects to occur.

Both drugs can be used to treat certain bacterial infections, and in some cases, your doctor may recommend taking both Flagyl and Cipro together. For example, your doctor may recommend taking Flagyl and Cipro for diverticulitis.

Cipro and Flagyl can cause gastrointestinal side effects, such as nausea, vomiting, and diarrhea. In addition, both drugs can cause skin rash, liver problems, and peripheral neuropathy.* So, taking a combination of these drugs may increase your risk of these side effects occurring.

However, Cipro can also cause tendon damage to occur, whereas Flagyl isn’t known to cause this side effect. So some side effects of the drugs do differ.

If you have questions about the side effects of Cipro and Flagyl, talk with your doctor or pharmacist.

What side effects will I have with the 500-mg Cipro tablet compared with the other strengths?

You may be at a higher risk of side effects if you take a higher dose of Cipro. This drug is available as a tablet that comes in strengths of 250 milligrams (mg) or 500 mg. It’s also available as a liquid suspension that comes in a strength of 250 mg/5 milliliters (mL) or 500 mg/5 mL.

If you take a 500-mg dose of Cipro, you may be at a higher risk of side effects than someone taking a dose of 250 mg. This is because when there is more of the drug in your body, side effects are more likely to occur.

If you’re concerned about side effects occurring during your treatment with Cipro, talk with your doctor. They can help make sure you’re taking the best dose of Cipro to treat your condition.

Should I expect long-term side effects with Cipro treatment?

Long-term side effects with Cipro aren’t common. However, they can occur. You may be at an increased risk of long-term side effects occurring if you take Cipro for an extended amount of time.

Examples of long-term side effects may include:

If you have concerns about long-term side effects occurring during your treatment with Cipro, talk with your doctor or pharmacist.

* Cipro has a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA). To learn more, see the “Side effect specifics” section below.

Learn more about some of the side effects that Cipro may cause. To find out how often side effects occurred in clinical trials, see the prescribing information for Cipro.

Risks of certain side effects

Inflamed or damaged tendon

It’s possible for Cipro to cause inflamed or damaged tendons, which can be serious. In fact, Cipro has a boxed warning for this side effect. A boxed warning is the most serious warning recommended by the Food and Drug Administration (FDA). The purpose of a boxed warning is to alert doctors and prescribers about the risks of taking a medication.

This side effect wasn’t reported in clinical trials. However, it was reported after Cipro came onto the market.

It’s possible for tendon rupture to occur within hours or days of starting Cipro. This can also occur several months after stopping Cipro. Symptoms may include leg pain, muscle pain, or swelling.

You may be at an increased risk of inflamed or damaged tendons if:

  • you’re age 60 years or older
  • you take corticosteroid drugs
  • you’ve had a kidney, heart, or lung transplant
  • you have kidney problems
  • you have a tendon problem

What you can do

Tell your doctor right away if you notice any pain or swelling during your treatment with Cipro. They can help make sure that your tendons aren’t inflamed.

In some cases, your doctor may recommend stopping Cipro if you develop pain or swelling of a tendon. If you have risk factors for inflamed or damaged tendons, your doctor may recommend a different treatment option for you.

Peripheral neuropathy

It’s possible for Cipro to cause peripheral neuropathy. This is a nerve condition that causes numbness or tingling in your hands, arms, feet, or legs. In fact, Cipro has a boxed warning for this side effect. A boxed warning is the most serious warning recommended by the FDA. The purpose of a boxed warning is to alert doctors and prescribers about the risks of taking a medication.

This side effect wasn’t reported in clinical trials. However, it was reported after Cipro came onto the market.

Symptoms of peripheral neuropathy may occur right after you start treatment with Cipro. In some rare cases, symptoms may not ease even after you stop treatment with Cipro.

What you can do

You should be aware of symptoms of peripheral neuropathy so that you can contact a doctor right away if you develop any. Symptoms may include:

  • numbness
  • pain
  • burning
  • tingling
  • weakness
  • changes in sensations such as pain or temperature

If you develop any of these symptoms while taking Cipro, talk with your doctor right away. They will likely recommend stopping treatment with Cipro. Then, they can recommend a different treatment option for you.

Central nervous system effects

It’s possible for Cipro to cause central nervous system (CNS) side effects. Cipro has a boxed warning for these risks. A boxed warning is the most serious warning recommended by the FDA. The purpose of a boxed warning is to alert doctors and prescribers about the risks of taking a medication.

This side effect wasn’t reported in clinical trials. However, it was reported after Cipro came onto the market.

CNS side effects may include:

What you can do

If you notice any changes in mood or symptoms of CNS side effects, be sure to tell your doctor right away. In this case, they may be able to recommend a different treatment option for your infection.

Worsening of myasthenia gravis

Cipro can worsen symptoms of myasthenia gravis, such as muscle weakness. Because of this risk, Cipro has a boxed warning for this side effect. A boxed warning is the most serious warning recommended by the FDA. The purpose of a boxed warning is to alert doctors and prescribers about the risks of taking a medication.

This side effect wasn’t reported in clinical trials. However, it was reported after Cipro came onto the market.

It’s possible for this side effect to be severe or even life threatening. In some cases, people with myasthenia gravis who took Cipro experienced difficulty breathing, which can be life threatening.

What you can do

Be sure to tell your doctor if you have a history of myasthenia gravis before you start treatment with Cipro. They will likely recommend a different treatment option for you in this case.

Allergic reaction

As with most drugs, Cipro can cause an allergic reaction in some people. In clinical trials, mild allergic reactions were common, and serious allergic reactions were rare.

Symptoms can be mild or serious and can include:

  • skin rash
  • itching
  • flushing
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What you can do

For mild symptoms of an allergic reaction, call your doctor right away. They may recommend ways to ease your symptoms and determine whether you should keep taking Cipro. However, if your symptoms are serious and you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Nausea

You may experience nausea from taking Cipro. In fact, nausea was one of the most common side effects that people taking Cipro reported in clinical trials.

What you can do

If you experience nausea during your treatment with Cipro, tell your doctor or pharmacist. In some cases, taking medications with food can decrease the risk of nausea. Your doctor or pharmacist can help determine the best ways to decrease any nausea that you experience.

Diarrhea

You may develop diarrhea during your treatment with Cipro. Diarrhea was one of the most common side effects that people taking Cipro reported in clinical trials.

In most cases, diarrhea is mild. However, it’s also possible for diarrhea to be a symptom of an infection called Clostridioides difficile (C. difficile). This infection can be serious and may cause other symptoms, including:

What you can do

If you develop diarrhea during your treatment with Cipro, talk with your doctor. They can help make sure that you don’t develop a C. difficile infection. They may also be able to recommend ways to treat your diarrhea. For example, your doctor may recommend taking an over-the-counter medication such as Imodium (loperamide).

Be sure to tell your doctor about any medical conditions that you have before starting Cipro.

Boxed warnings

This drug has boxed warnings about a risk of severe side effects and a risk of worsening of myasthenia gravis. These are serious warnings from the Food and Drug Administration (FDA). For details, see the “Side effect specifics” section above.

Other precautions

Be sure to talk with your doctor about your health history before you take Cipro. This drug may not be the right treatment option for you if you have certain medical conditions or other factors that affect your health. These are known as drug-condition or drug-factor interactions. The conditions and factors to consider include:

Mood problems. It’s possible for Cipro to cause changes in mood. If you already have a mood condition, such as depression, taking Cipro may make your condition worse. Your doctor may recommend more frequent monitoring of your condition. In some cases, they may recommend a different treatment option for you.

Myasthenia gravis. Tell your doctor if you have myasthenia gravis before starting Cipro. This medication can cause worsening muscle weakness, which may make symptoms of myasthenia gravis worse. Due to this risk, your doctor will likely recommend a drug other than Cipro if you have myasthenia gravis.

Low blood potassium or magnesium levels. If you have a low blood potassium level or magnesium level, tell your doctor before starting Cipro. This drug can increase your risk of a heart rhythm problem called long QT syndrome. If you have a low blood potassium or magnesium level, you may be at a higher risk of long QT syndrome occurring. In this case, your doctor can help manage your low blood potassium or magnesium level before you take Cipro.

Kidney problems. Tell your doctor about any kidney problems that you have before taking Cipro. In some cases, your dose of Cipro may need to be decreased if you have kidney problems. Your doctor can help determine what the best dose of Cipro for you is based on your kidney problems.

Older adults. If you’re an older adult (age 65 years or older), you may be at an increased risk of certain side effects, such as tendon rupture or heart problems, from taking Cipro. In this case, your doctor may recommend frequent monitoring during your treatment with Cipro.

Diabetes or low blood sugar level. If you have diabetes or a low blood sugar level, tell your doctor before taking Cipro. It’s possible that taking Cipro with certain diabetes medications may increase your risk of changes in blood sugar. So your doctor may recommend more frequent monitoring of your blood sugar level in this case.

Allergic reaction. If you’ve had an allergic reaction to Cipro or any of its ingredients, your doctor will likely not prescribe Cipro. Ask your doctor what other medications may be better options for you.

Liver problems. Liver problems can occur from Cipro. If you already have a liver condition such as cirrhosis, taking Cipro may make your condition worse. Your doctor can help determine whether Cipro is safe for you to take if you have any liver conditions.

Sun sensitivity. Cipro may increase your risk of sunburn and may make your skin more sensitive to the sun. Because of this, your doctor may recommend wearing sunblock or wearing clothing to protect your skin while you’re taking Cipro.

Seizures. Tell your doctor if you have a history of seizures or seizure disorders. Although rare, it’s possible for Cipro to cause seizures to occur. And if you have a history of seizures, taking this medication may increase your risk further. Your doctor can help determine whether Cipro may be safe for you in this case.

Aortic aneurysm. If you’ve ever had an aortic aneurysm, tell your doctor before taking Cipro. In some cases, this medication can increase your risk of aortic dissection. You may also be at an increased risk of this condition if you’ve had an aortic aneurysm. In this case, your doctor may recommend a different treatment option for you.

Long QT syndrome. It’s possible for Cipro to cause long QT syndrome. And if you already have this condition, taking Cipro may make your condition worse. In this case, your doctor can help determine whether Cipro is a safe treatment option for you.

Tendon problems. Tell your doctor about any tendon problems that you have. Cipro may cause tendon problems, including tendon damage, to occur. If you already have tendon problems, taking Cipro may make your condition worse. In this case, your doctor can help determine whether Cipro is a safe treatment option for you.

Peripheral neuropathy. It’s possible for Cipro to cause peripheral neuropathy. If you already have this condition, taking Cipro may make it worse. Your doctor can help determine whether Cipro is safe for you.

Joint problems. If you have any joint problems, such as rheumatoid arthritis, tell your doctor before taking Cipro. It’s possible for this medication to cause joint problems. And if you already have a condition affecting your joints, taking Cipro can make it worse. Your doctor can help determine whether Cipro is safe for you.

Alcohol with Cipro

There aren’t any known interactions between Cipro and alcohol. However, it’s possible that drinking alcohol while taking Cipro may increase your risk of side effects. For example, both alcohol and Cipro can cause nausea, vomiting, and liver problems. So taking a combination of alcohol and Cipro can increase your risk of these side effects occurring.

If you have questions about drinking alcohol while taking Cipro, talk with your doctor.

Pregnancy and breastfeeding while taking Cipro

It’s not known whether it is safe to take Cipro during pregnancy.

There have been some clinical trials done on pregnant people who have taken Cipro. Some don’t seem to show any increased risks when Cipro is taken during pregnancy. However, there’s not enough information to determine whether Cipro may cause any increased risks when it’s taken during pregnancy.

You should avoid breastfeeding while taking this drug. Cipro can pass into breast milk, meaning a child who is breastfed could be exposed to the drug. Because of this risk, it’s not recommended to breastfeed while taking Cipro or for at least 2 days after stopping treatment. During this time, you can pump breast milk and discard it, if needed.

If you’re pregnant, planning to become pregnant, or breastfeeding, talk with your doctor before taking Cipro.

You may experience side effects from taking Cipro. Though most side effects are mild, it’s possible for some side effects to be serious.

If you’d like to learn more about Cipro, talk with your doctor or pharmacist. They can help answer any questions you have about side effects from taking the drug.

Besides talking with your doctor, you can do some research on your own. These articles might help:

  • More information about Cipro. For details about other aspects of Cipro, refer to this article.
  • Drug comparison. To learn how Cipro compares with Bactrim, Macrobid, levofloxacin, and cephalexin, view this article.
  • Interactions. To find out about Cipro’s interactions, see this article.
  • A look at your condition. For details about infections, see this list of articles. To learn about Cipro and urinary tract infections (UTIs), see this article.

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.