Cipro Side Effects

As of June 30, 2024, based on generic ciprofloxacin and three Cipro brand name products – Cipro, Cipro XR and Proquin XR – the U.S. Food and Drug Administration classified most of the side effect reports they received as serious.

Drug hypersensitivity, joint stiffness, pain (including joint and extremity pain), fatigue and gastrointestinal disorders were the most common Cipro side effects reported to the FDA.

GI symptoms include diarrhea, nausea, vomiting and abdominal pain. Additional side effects frequently reported were rash and dizziness.

Disclaimer: Reports sent to the FDA don’t necessarily mean the drug caused an adverse event. Consult a health care professional before stopping or changing medication.

The number of cases and severe reactions reported to the FDA represent a small percentage of the millions of Cipro prescriptions filled each year. Overall, the medication has an excellent safety profile for individuals who are not allergic or sensitive to its ingredients. Nevertheless, it’s a good idea to discuss any safety concerns you have with a doctor before taking Cipro or any new medications.

FDA Warnings

On July 10, 2018, the FDA updated label guidance on Cipro and other fluoroquinolone antibiotics to include a warning about mental health disturbances and the risk of low blood sugar leading to coma. There have been several updates over the years.

Boxed warnings are the strictest warnings the FDA mandates. Manufacturers must list the warning in a prominent location and develop a patient treatment guide for the mentioned side effects.

According to the drug’s prescribing information, the most common side effects of Cipro reported in clinical trials include gastrointestinal upset (5.1%), abnormal results from liver function tests (1.3%) and rash (1%). Pediatric trial participants displayed a high percentage of musculoskeletal reactions.

Cipro may also cause photosensitivity, which can lead to severe sunburn. Patients taking it can use sunscreen and limit their exposure to sunlight and UV rays to reduce this effect.

Cipro and other fluoroquinolones can cause significant, serious and potentially life-threatening side effects. Tendon damage, peripheral neuropathy and changes to blood sugar levels are among the most frequently reported severe side effects. However, there are other potentially severe reactions that occur less frequently.

In general, fluoroquinolones carry a higher risk of serious adverse reactions than other classes of antibiotics. A 2021 study published in the JAMA network showed a decrease in prescriptions for Cipro following repeated FDA warnings about potentially serious side effects.

Tendonitis and Ruptured Tendons

Cipro is directly associated with a higher incidence of tendon injuries. The most commonly affected tendon is the Achilles tendon. Two 2022 studies published in Frontiers in Pharmacology found an increased risk of tendonitis among patients taking fluoroquinolones.

Among this class of drugs, Cipro resulted in higher rates of tendonitis and had the most severe tendon injuries. The risk of tendonitis or tendon rupture is so great that the FDA mandated a boxed warning for it in 2008.

Certain patients were more likely to experience tendonitis and ruptured tendons when taking Cipro. If you are at increased risk of developing a tendon injury when taking fluoroquinolones, speak to your doctor about alternative medications or ways to protect yourself.

Mental Health Disturbances

Cipro can cause potentially serious mental health disturbances. These can appear after a single dose. Patients experiencing new or worsening mental health-related symptoms should report this to their health care provider immediately.

According to a 2018 FDA safety communication, Cipro packaging and medication inserts must contain a prominent warning about the following six mental health disturbances: anxiety, psychotic reactions or hallucinations, delirium or disorientation, memory impairment, depression or self-harm and nightmares or insomnia.

Low Blood Sugar and Coma

Researchers have documented changes in blood sugar levels with Cipro use for many years. For example, a 2022 study published in Diabetes Research and Clinical Practice showed an increased risk of severe low blood sugar among those using drugs like Cipro.

In 2018, the FDA released an updated safety bulletin stating that “Low blood sugar levels can result in serious problems, including coma, particularly in older people and patients with diabetes who are taking medicines to reduce blood sugar.” An agency review of data on Cipro’s side effects prompted this update.

Careful monitoring and early symptom reporting can help reduce the chance of life-threatening complications. Before beginning a Cipro course, you should discuss any other medications you take with your health care provider.

Peripheral Neuropathy

The FDA’s 2013 safety bulletin addressed a link between Cipro and peripheral neuropathy – a nerve condition that can be disabling. According to the announcement, package information must include clear wording about the possibility of developing the condition. Symptoms may include a pins and needles sensation in your limbs, difficulty moving, decreased coordination and touch sensitivity.

Peripheral neuropathy may develop immediately after beginning Cipro and can lead to permanent nerve damage.

Aortic Aneurysms

Cipro may weaken arteries, leading to aneurysms or bulges in artery walls. These are serious medical conditions that often display no symptoms or few symptoms in the early stages. However, it can quickly turn life-threatening. If an aneurysm grows large enough, it can burst.

Jerry Conway told the Drugwatch Podcast that he suffered an aortic dissection after taking Cipro.

“I was admitted to Plano Presbyterian Hospital’s ER, was given last rites,” Conway told Drugwatch. “I had no idea what was going on.”

He had been taking Cipro long-term. He estimates he took 20 to 25 full prescriptions for the antibiotic.

“Cipro was being hailed as the wonder drug and it really did knock it out of the park with the first dosage,” Conway said. But after his aneurysm, he underwent an 11-hour surgical procedure and was in a medically induced coma for a month.

“I went from a guy who would walk five and a half miles a day, to a guy that can barely walk to and from the car to get to work.”

Patients injured by fluoroquinolones brought multiple Cipro lawsuits against the manufacturers of Cipro, Avelox and Levaquin. They allege that patients experienced effects such as tendon rupture, peripheral neuropathy, aortic rupture, dissection and aneurysm due to their antibiotic use. Some lawsuits are on behalf of family members who died from complications.

The FDA recommends avoiding Cipro for infections that respond well to other therapies. Generally, patients should try the available alternatives before using Cipro.

Fluoroquinolones, like Cipro, are a class of drugs that work by preventing bacteria from creating DNA. Other antibiotics work differently. Penicillin, for example, prevents bacteria from forming cell walls.

The most suitable alternative medication depends on the type of infection being treated. For example, doctors use doxycycline to treat sexually transmitted infections, skin conditions and dental infections. They often prescribe vancomycin for strep infections, colitis and certain types of bacteria-caused diarrhea.

Drug resistance, drug sensitivities and your medical history can also play a role. Your health care provider can help you find an appropriate treatment.

Editor Lindsay Donaldson contributed to this article.