Can you take ciprofloxacin and metronidazole together?

In this article:

• Key differences
• Can you take ciprofloxacin and metronidazole together?
• How to take ciprofloxacin and metronidazole together
• Metronidazole and ciprofloxacin together side effects
• Is ciprofloxacin or metronidazole better?
• Ciprofloxacin vs. metronidazole: Comparison chart

In this article

• Key differences
• Can you take ciprofloxacin and metronidazole together?
• How to take ciprofloxacin and metronidazole together
• Metronidazole and ciprofloxacin together side effects
• Is ciprofloxacin or metronidazole better?
• Ciprofloxacin vs. metronidazole: Comparison chart

Healthcare professionals may prescribe antibiotics such as ciprofloxacin or metronidazole when treating certain bacterial infections. These medications are effective in helping the body fight infections by stopping bacteria from growing. However, they work differently, and they’re used for different types of infections. We’ll review the safety and efficacy of using these two antibiotics together, discuss their potential side effects and interactions to be aware of, and outline important precautions to consider under the supervision of a healthcare provider. 

Ciprofloxacin vs. metronidazole: Key differences

In order to understand why these drugs may be taken together and how to take them together, it may help to understand how they work. Ciprofloxacin, commonly called “cipro” is a broad-spectrum antibiotic that belongs to a class of medications called fluoroquinolones (quinolones), which treat various bacterial infections, including respiratory, gastrointestinal, and urinary tract infections (UTIs). They also treat rare bacterial infections like typhoid fever, severe internal infections of the bones, joints, prostate, or abdomen, and pathogens used in bioterrorism attacks like anthrax or plague. Ciprofloxacin works by stopping the ability of bacterial cells to divide and repair themselves, effectively killing the bacteria and preventing them from growing in the body.

Ciprofloxacin is available as tablets, extended-release tablets, and oral suspension (liquid). The usual adult dose is 250–750 milligrams (mg) twice a day, depending on the infection.

Metronidazole, on the other hand, is both an antibiotic and an antiprotozoal medication that belongs to a class of medications called nitroimidazoles. It treats infections caused by anaerobic bacteria—bacteria that grow and thrive in environments without oxygen. Metronidazole is commonly prescribed for conditions like bacterial vaginosis, trichomoniasis, lower respiratory tract infections, rosacea, pelvic inflammatory disease, and infections of the stomach or intestines. It works by breaking and damaging the DNA of bacteria and parasites, which kills them.

Metronidazole is available in tablets, extended-release tablets, gel, cream, oral suspension, and injection. The typical adult dose is 500 mg every eight hours or 750 mg every 12 hours, depending on the infection.

Can you take ciprofloxacin and metronidazole together?

Yes, ciprofloxacin and metronidazole can be taken together in certain situations, but this should always be done under the guidance of your healthcare provider. These antibiotics may be prescribed together for infections involving different types of bacteria. Examples include diverticulitis, Crohn’s disease, and specific infections involving the teeth or gums.

Using ciprofloxacin together with metronidazole may result in drug interaction that can increase the risk of irregular heart rhythms. This is a rare side effect; however, it can be serious and potentially life-threatening. If you have heart disease, a pre-existing heart condition called congenital long QT syndrome, or electrolyte disturbances (due to severe or prolonged diarrhea or vomiting), you may be more susceptible to this side effect.

While taking these antibiotics together or on their own, talk with your healthcare professional or seek medical attention if you experience sudden dizziness, lightheadedness, shortness of breath, or heart palpitations (heart beating fast). Inform your healthcare provider about all other medications you are using, including vitamins and herbal supplements. Never stop taking any medications without first consulting your healthcare provider.

Several studies have looked at using these antibiotics together:

1. A study published in the Canadian Journal of Gastroenterology examined the use of ciprofloxacin and metronidazole together to treat serious infections in the belly area. In the study, ciprofloxacin and metronidazole were reported to be well-tolerated. They seemed helpful in bringing about clinical remission for patients with active Crohn’s disease, especially when the colon is affected.
2. Another study published in The Lancet Gastroenterology and Hepatology found that giving oral antibiotics (ciprofloxacin and metronidazole) the day before colon surgery, as a preventive measure, significantly lowers the risk of surgical-site infections. This can be done without mechanical bowel preparation and should be routinely used before elective colon surgery.

Even though some studies suggest that ciprofloxacin and metronidazole can be used together, everyone’s body reacts differently. What works for one person might not be the best option for another. Your healthcare provider will consider factors such as the following before prescribing both antibiotics:

• The type of infection you have
• How severe your infection is
• Your overall health
• Other medications you’re taking
• Your risk for side effects

How to take ciprofloxacin and metronidazole together

Ciprofloxacin and metronidazole may individually interact with other medications you are taking. If your healthcare provider prescribes both antibiotics, they’ll typically instruct you to take them at different times throughout the day to minimize the risk of side effects and to ensure each drug can work effectively. 

Taking ciprofloxacin 

This antibiotic is usually taken twice daily, with or without food. Some drugs may reduce the effectiveness of Cipro. Take Cipro tablets at least two hours before or six hours after taking the following medications:

• Antacids or multivitamins that contain aluminum, magnesium, lanthanum, iron, or zinc
• The stomach protectant, sucralfate
• The HIV/AIDS drug didanosine
• Phosphate binders

Ciprofloxacin may increase the effects of caffeine, such as restlessness, nervousness, and trouble sleeping. People on ciprofloxacin may need to reduce their caffeine intake. It’s also important to drink plenty of water while taking ciprofloxacin to help flush your system and reduce the risk of side effects such as crystalluria (the formation of crystals in the urine).

Taking metronidazole

Metronidazole is generally taken two to three times a day. It is advisable to take it with food to reduce an upset stomach. An important warning when using metronidazole is to avoid alcohol during treatment and for at least 72 hours (three days) after completing the medication, as this combination can lead to severe nausea, vomiting, and abdominal cramps.

Taking cipro and metronidazole together

Here are some general tips to follow while taking both antibiotics together:

• Take each medication exactly as prescribed. Do not alter the dosage or timing without consulting your healthcare provider first.
• Take ciprofloxacin with a full glass of water. It can be taken with or without food, but if it causes an upset stomach, consider taking it with food. 
• Take metronidazole with food to help prevent gastrointestinal discomfort.
• Avoid alcohol while taking metronidazole and for at least 72 hours after finishing the medication, as this combination can lead to severe nausea and vomiting.
• Refrain from consuming dairy products, calcium-fortified juices, and antacids for a few hours before and after taking ciprofloxacin, as these can interfere with the antibiotic’s effectiveness.

Metronidazole and ciprofloxacin together side effects

Taking ciprofloxacin and metronidazole together can increase the likelihood of experiencing side effects. 

Ciprofloxacin side effects include nausea, diarrhea, dizziness, and photosensitivity (increased sensitivity to sunlight). In rare cases, ciprofloxacin can cause more serious side effects like tendonitis or even tendon rupture, particularly in older adults or people who are also taking corticosteroids.

Metronidazole side effects include nausea, a metallic taste in the mouth, and stomach upset. More severe side effects include peripheral neuropathy (numbness or tingling in the hands and feet) if taken for long periods.

When taken together, these side effects may be more pronounced. For example, both drugs can cause gastrointestinal issues, so combining them could increase the risk of nausea, vomiting, or diarrhea. It’s important to monitor how your body responds during this time and inform your healthcare provider if you experience severe or persistent side effects.

Common side effects that both medications can cause include:

• Nausea and vomiting
• Diarrhea
• Headache
• Dizziness
• Stomach pain

Rare and severe side effects can happen. These might include:

• Allergic reactions (like rash, itching, or trouble breathing)
• Tendon problems (more likely with ciprofloxacin)
• Nerve problems (like tingling or numbness)
• Mood changes
• Seizures (in rare cases)

Communicate with your healthcare provider immediately if you have any unusual symptoms while taking these medications. Also, remember that this list doesn’t include all possible side effects. Your healthcare provider or pharmacist can give you more information about what to watch out for.

Is ciprofloxacin or metronidazole better?

The choice between ciprofloxacin and metronidazole depends on the type of infection being treated. Your healthcare professional can discuss which medication is the best option for you. Ciprofloxacin is more effective against aerobic bacteria, while metronidazole targets anaerobic bacteria. Both drugs may be necessary for infections caused by a combination of both types of bacteria.

Both ciprofloxacin and metronidazole are effective antibiotics, but they target different types of infections. Ciprofloxacin is typically preferred for treating respiratory and urinary tract infections, while metronidazole is the go-to choice for anaerobic infections, such as bacterial vaginosis and certain gastrointestinal infections.

A 2010 study found that metronidazole worked better than other antibiotics in treating certain types of infections, specifically the anaerobic ones. 

An earlier study from 2001 focused on evaluating the use of ciprofloxacin versus metronidazole to treat acute pouchitis—a common problem that happens in people who have had surgery to remove part of their colon (large intestine) and create a new internal pouch to hold waste. It suggested that ciprofloxacin should be considered a first-line treatment for this condition.

It’s important to understand that a healthcare provider familiar with your complete medical history should always decide whether to use ciprofloxacin, metronidazole, or both. Discussing medical decisions with your healthcare provider ensures that you receive the most appropriate treatment for your condition.

Bottom line

Ciprofloxacin and metronidazole can be taken together safely to treat certain infections, but only with a healthcare provider’s supervision. These antibiotics can interact with each other, and combining them may increase the risk of side effects like stomach problems. It’s important to follow your healthcare provider’s instructions closely and not change your dose without talking to them. 

You should also tell your healthcare provider if you’re taking other medications or supplements. This is important for avoiding harmful interactions. While this combination can be effective for some infections, it’s not right for everyone, which is why personalized medical advice is essential.