What is Cephalexin?

Cephalexin is a type of antibiotic known as a cephalosporin antibiotic. These drugs are prescribed for people with certain types of bacterial infections and generally can be used as a safe penicillin alternative by people who are allergic to this antibiotic. Cephalexin also is known as cefalexin and is sold under brand names such as Keflex®, Panixine® and Zartan®.

Most bacterial cells have cell walls, within which are contained all of the liquid and molecular components of the cell. Maintaining the integrity of the cell wall is crucial for bacterial survival. Cephalexin and other cephalosporin antibiotics kill bacterial cells by interfering with the ability of the cells to build and repair their walls. When the integrity of the bacterial cell walls is impaired, cells affected by these antibiotics burst open and die.

Cephalexin is a commonly prescribed antibiotic treatment for respiratory tract infections, urinary tract infections and infections of the skin and soft tissue. In addition, it is a common first-line treatment for deep skin infections such as cellulitis. Occasionally, this antibiotic is prescribed as an acne treatment. As with all antibiotics, the full prescribed course should be taken, even if symptoms subside after a few days. This is important because bacteria still alive at the end of an interrupted course of antibiotics can develop resistance to the drug.

This medication can cause a wide range of side effects. Possible effects include dizziness, headache, indigestion, stomach pain, diarrhea, joint pain and tiredness. Women who take this antibiotic might temporarily have an increased risk of developing a vaginal yeast infection. This is because the antibiotic can sometimes kill bacteria that naturally live in the vagina, allowing yeasts to grow more extensively.

More serious side effects can include yellowing of the skin or eyes as in jaundice, peeling or blistering of the skin, reduced urine output, unexplained bleeding or bruising, abdominal cramps and confusion. These symptoms require prompt medical attention from a doctor, to ensure that they are adequately treated. It is rare for someone to have an allergic reaction to this antibiotic, but it can and does occur, causing symptoms such as skin itching and rash, swelling of the face or mouth and breathing difficulty. These allergic symptoms require immediate emergency medical attention.

The risk of serious side effects as a result of taking cephalexin can be increased in people who have liver or kidney disease or a gastrointestinal disease such as colitis. People with diabetes also have an increased risk of serious side effects. Depending on the type of infection and the type of pre-existing disease that a patient has, his or her doctor might prescribe an adjusted dose of the antibiotic or a different drug altogether.