Cephalexin, an antibiotic in the cephalosporin family, is used to treat infections caused by bacteria. Cephalexin is prescribed to treat respiratory tract, middle ear, skin, bone, and urinary. What other drugs will affect cephalexin? Metformin, probenecid, and blood-thinners may all interact with cephalexin. Other drugs may also interact with cephalexin, including prescription and over-the-counter medicines, vitamins, and herbal products. Cephalexin comes as a capsule, tablet, and suspension (liquid) to take by mouth. It is usually taken with or without food every 6 or 12 hours for 7 to 14 days, depending on the condition being treated. What other drugs will affect Keflex? Metformin (a diabetes drug) and probenecid (an antibiotic) have been shown to interact with Keflex. Other drugs may interact with Keflex, including prescription and over-the-counter medicines, vitamins, and herbal products. At some point most dogs are going to need a dose of antibiotics, either as a preventative measure or to cure an infection of some type. What is cephalexin used for? This eMedTV page explains that this prescription antibiotic can treat bacterial infections and prevent heart valve infections. It can also be a substitute for penicillin if a person is allergic to that particular drug. Cephalexin (Keflex, Keftabs) is an an antibiotic used to treat bacterial infections of the sinuses, tooth, urinary tract, and throat. Common side effects of Keflex include diarrhea, nausea, abdominal pain, headaches, and vaginitis. Dosage of cephalexin depends on the type of infection. Recent Examples on the Web. The most common organism responsible for perichondritis is a bug called Pseudomonas aeruginosa, a virulent pathogen with the ability to resist many antibiotics, including the cephalexin prescribed by Jessica’s pediatrician. Cefalexin, also spelled cephalexin, is an antibiotic that can treat a number of bacterial infections. It kills gram-positive and some gram-negative bacteria by disrupting the growth of the bacterial cell wall. Cefalexin is a beta-lactam antibiotic within the class of first-generation cephalosporins. It works similarly to other agents within. Compare prices and print coupons for Cephalexin (Generic Keftab, Keflet, and Keflex) and other Skin Infection, Ear Infection, Urinary Tract Infection, Bacterial Infection, Lower Respiratory Infection, and Upper Respiratory Infection drugs at CVS, Walgreens, and other pharmacies. Prices start at $6.76.