Known brand names include Cipro.
A fluoroquinolone antibiotic taken by mouth for urinary, skin, bone and joint, abdominal, lung, and some intestinal infections, and after anthrax or plague exposure. Because it can cause disabling tendon, nerve, and brain side effects, it is reserved for cases with no other option in uncomplicated cystitis, sinusitis, and bronchitis flares.
Ciprofloxacin blocks DNA gyrase and topoisomerase IV, enzymes that bacteria need to copy and repair their DNA. Without them, the bacteria die. Taken by mouth, most of it is absorbed and spreads widely through the body, often reaching higher levels in tissues such as the prostate than in the blood.
It reaches its highest level in the blood 1 to 2 hours after a dose, and people should start to feel better within the first few days. Dairy products or calcium-fortified juices taken on their own with it can lower how much is absorbed, though a meal that includes them is fine. It also slows a liver enzyme that breaks down some other medicines, which can raise the levels of drugs such as theophylline and tizanidine.
Ciprofloxacin is an antibiotic pill that kills the bacteria behind a range of infections. It treats infections of the urinary tract, skin, bones and joints, belly, and lungs, along with infectious diarrhea and typhoid fever, a serious illness caused by Salmonella bacteria. It also treats gonorrhea of the cervix or urethra and chronic bacterial prostatitis, a long-lasting infection of the prostate gland. It is used after breathing in anthrax and to treat or prevent plague.
Most of its uses are for adults 18 and older. Children up to 17 take it only for anthrax exposure, plague, and complicated urinary and kidney infections, and even then it is not a first choice because of joint problems. For belly infections, it is taken together with another antibiotic, metronidazole. Because of its serious side effects, it is used for simple bladder infections, sinus infections, and bronchitis flares only when there is no other choice.
Nausea, diarrhea, vomiting, liver test changes, and rash are the common side effects. The label treats tendon damage and rupture as a major risk, most often in the Achilles tendon, along with nerve damage that may be permanent. It also warns about seizures, confusion, and mood changes, worse myasthenia gravis, heart rhythm changes, a bulge or tear in the aorta, very high or low blood sugar, liver injury, serious allergic reactions, severe sunburn, and C. difficile diarrhea.
This is the boxed warning, the warning the FDA label prints first.
Fluoroquinolones can cause disabling, possibly permanent reactions that may occur together: tendinitis and tendon rupture, peripheral neuropathy, and CNS effects. Stop ciprofloxacin at once and avoid all fluoroquinolones after any of these. It can worsen myasthenia gravis; avoid it in patients with that history. Reserve it for patients without other options in bronchitis flares, uncomplicated cystitis, and acute sinusitis.
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