Ciprofloxacin and ibuprofen perform two different functions in medicine. While ciprofloxacin is an antibiotic and combats bacterial infections, ibuprofen is an anti-inflammatory medication. Both of these drugs, however, can act on the central nervous system and, together, increase the risk of convulsions.
Scientists typically group medicines together by molecular similarity. Ciprofloxacin is part of the quinolone group, which contains a variety of antibiotics. Generally, specific groups share many biological characteristics, such as mode of action and possible side effects. If doctors notice one particular quinolone antibiotic has an unwanted effect on the body, then as a precaution, they assume the other quinolones have the potential to cause the same problem.
In the case of ciprofloxacin, the problem that scientists noticed with certain members of the group was that the drugs could be toxic to the central nervous system. Patients under treatment with the antibiotics could suffer tremors and muscle twitches and experience hallucinations. Seizures could also occur, especially if the patient had had seizures in the past. How the drug acts on the body to cause these problems is not yet known, as of 2011, although it may be because the medication blocks certain brain signals.
Ibuprofen is also part of a group of medications. In this case, the group members are called nonsteroidal anti-inflammatory drugs (NSAIDs.) Diclofenac and aspirin are other members of the NSAID group. The presence of ciprofloxacin and ibuprofen in the same body together can make the potentially toxic effect of the quinolone to the nervous system worse than if the antibiotic were present alone.
Despite the theoretical risk of a treatment regimen with both ciprofloxacin and ibuprofen, a doctor may be able to prescribe the two medications together. In this case, he or she makes an informed decision about the risks with the patient, balancing the potential for convulsions against the damage to the patient from the illness. Anyone with a history of epilepsy or other brain problems may be ruled out as a potential candidate for the treatment.
As well as potential problems with ciprofloxacin and ibuprofen, ciprofloxacin may be unsuitable for people using corticosteroid drugs or people who have allergies to the quinolone group of antibiotics. Medical conditions that may rule out ciprofloxacin treatment regimes include myasthenia gravis, a muscle condition, previous issues with tendinitis, and diabetes. Patients with glucose 6-phosphate dehydrogenase deficiency and those with kidney problems also need to inform the doctor prior to taking the drug. Children, pregnant women, or breast-feeding women may also be safer with a different form of treatment.