Cephalosporins are a type of antibiotic, or medicines that kill bacteria or prevent their growth.
Cephalosporins are used to treat infections in different parts of the body—the ears, nose, throat, lungs, sinuses, and skin, for example. Physicians may prescribe these drugs to treat pneumonia, strep throat, staph infections, tonsillitis, bronchitis, and gonorrhea. These drugs will not work for colds, flu, and other infections caused by viruses.
Cephalosporins are also commonly used for surgical prophylaxis—prevention of bacterial infection during or immediately after surgery. For this purpose, a single injection may be given during the surgical procedure. In some cases, the cephalosporin may be continued for 24 to 48 hours after surgery. If, in spite of all precautions, an infection develops, the antibiotics may be continued until the infection has resolved.
Examples of cephalosporins are cefaclor (Ceclor), cefadroxil (Duricef), cefazolin (Ancef, Kefzol, Zolicef), cefixime, (Suprax), cefoxitin (Mefoxin), cefprozil (Cefzil), ceftazidime (Ceptaz, Fortaz, Tazicef, Tazideme), cefuroxime (Ceftin) and cephalexin (Keflex). These medicines are available only with a physician's prescription. They are sold in tablet, capsule, liquid, and injectable forms.
Cephalosporins are sometimes referred to as first, second, and third generation. Each "generation" is effective against more types of bacteria than the one before it. In addition, each subsequent generation is better at getting into the central nervous system (the brain and spinal cord).
Cephalosporins are chemically similar to penicillins, and to other types of antibiotics called cephamycins.
The recommended dosage depends on the type of cephalosporin. The physician who prescribed the drug or the pharmacist who filled the prescription should be consulted for the correct dosage.
The following recommendations do not apply when cephalosporins are given as a single intravenous dose prior to or during surgery. The recommendations should be considered if the drugs are used afterwards to treat a surgical infection, particularly if the cephalosporins are given by mouth.
Cephalosporins should be taken exactly as directed by the physician. The patient should never take larger, smaller, more frequent, or less frequent doses than prescribed. The drug should be taken for exactly as long as directed. No doses of the drug should be saved to take for future infections, because the medicine may not be right for other kinds of infections, even if the symptoms are the same. In addition, all of the medicine should be taken to treat the infection for which it was prescribed. The infection may not clear up completely if too little medicine is taken. Taking this medicine for too long, on the other hand, may open the door to new infections that do not respond to the drug.
Some cephalosporins work best when taken on an empty stomach. Others should be taken after meals. The physician who prescribed the medicine or the pharmacist who filled the prescription should give instructions as to how to take the medicine.
When given for surgical prophylaxis, it used to be common practice to give a dose of a cephalosporin as soon as the patient has been called to the operating room . More recently, the practice has been to give a single dose during the surgical procedure. This works just as well as the "on call" dose, and lowers the amount of antibiotic that the patient must take.
The following recommendations do not apply when cephalosporins are given as a single intravenous dose prior to or during surgery. They should be considered if the drugs are used afterwards to treat a surgical infection, particularly if the cephalosporins are given by mouth.
Certain cephalosporins should not be combined with alcohol or with medicines that contain alcohol. Abdominal or stomach cramps, nausea, vomiting, facial flushing, and other symptoms may result within 15–30 minutes and may last for several hours. Alcoholic beverages as well as other medicines that contain alcohol should be avoided while being treated with cephalosporins and for several days after treatment ends.
People with certain medical conditions or who are taking certain other medicines can have problems if they take cephalosporins. Before taking these drugs, be sure to let the physician know about any of these conditions:
ALLERGIES. Severe allergic reactions to this medicine may occur. Anyone who is allergic to cephalosporins of any kind should not take other cephalosporins. Anyone who is allergic to penicillin should check with a physician before taking any cephalosporin. The physician should also be told about any allergies to foods, dyes, preservatives, or other substances. The type of allergic reaction should be discussed in detail, since some people have reactions to a drug that are not truly allergies. These people may be able to take cephalosporins safely.
DIABETES. Some cephalosporins may cause false positive results on urine sugar tests for diabetes. People with diabetes should check with their physicians to see if they need to adjust their medication or their diets.
PHENYLKETONURIA. Oral suspensions of cefprozil contain phenylalanine. People with phenylketonuria (PKU) should consult a physician before taking this medicine.
PREGNANCY. Women who are pregnant or who may become pregnant should check with their physicians before using cephalosporins.
BREASTFEEDING. Cephalosporins may pass into breast milk and may affect nursing babies. Women who are breast-feeding and who need to take this medicine should check with their physicians. They may need to stop breast-feeding until treatment is finished.
OTHER MEDICAL CONDITIONS. Before using cephalosporins, people with any of these medical problems should make sure their physicians are aware of their conditions:
USE OF CERTAIN MEDICINES. Taking cephalosporins with certain other drugs may affect the way the drugs work or may increase the chance of side effects.
The patient should get medical attention immediately if any of these symptoms develop while taking cephalosporins:
Other rare side effects may occur. Anyone who has unusual symptoms during or after treatment with cephalosporins should contact his or her physician.
Some cephalosporins cause diarrhea. Certain diarrhea medicines, such as diphenoxylate-atropine (Lomotil), may make the problem worse. Check with a physician before taking any medicine for diarrhea caused by taking cephalosporins.
Birth control pills may not work properly when taken at the same time as cephalosporins. To prevent pregnancy, other methods of birth control in addition to the pills are advised while taking cephalosporins.
Taking cephalosporins with certain other drugs may increase the risk of excess bleeding. Among the drugs that may have this effect when taken with cephalosporins are:
Cephalosporins may also interact with other medicines. When this happens, the effects of one or both of the drugs may change or the risk of side effects may be greater. Anyone who takes cephalosporins should let the physician know all other medicines he or she is taking.
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Nancy Ross-Flanigan Sam Uretsky