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Compare Cephalexin vs. Ceftriaxone

Head-to-head comparisons of medication uses, side effects, warnings, and more.

Key takeaways

Cephalexin (Keflex) and ceftriaxone (Rocephin) are both cephalosporin antibiotics used to treat bacterial infections, including urinary tract infections (UTIs) and ear infections. However, they differ in several ways. Cephalexin is taken orally as capsules, tablets, or liquid suspensions, while ceftriaxone is given as an injection into the veins or muscles, usually in a healthcare setting. Cephalexin is typically taken 2 to 4 times a day, whereas ceftriaxone is usually given once a day. Both medications are available as a lower-cost generic. Common side effects of cephalexin include nausea, vomiting, and diarrhea, while ceftriaxone can cause injection site pain and, less commonly, nervous system side effects like confusion and seizures. Cephalexin may interact with medications like metformin and probenecid, whereas ceftriaxone should not be mixed with calcium-containing medications and also interacts with probenecid.

  • Cephalexin
    Ceftriaxone
  • Cephalexin
    Ceftriaxone

  • Summary of Cephalexin vs. Ceftriaxone

    Summary for Cephalosporin antibiotic
    Prescription only

    Cephalexin, also commonly known as Keflex, is a cephalosporin antibiotic for people ages 1 year and older. It can treat many types of bacterial infections. This includes ear infections, skin infections like cellulitis, urinary tract infections (UTIs), and strep throat. Cephalexin comes as capsules, tablets, and a liquid suspension. It's taken by mouth 2 to 4 times per day. Side effects can include nausea, vomiting, and diarrhea. Cephalexin is a generic medication; its brand name Keflex is no longer available.

    Summary for Cephalosporin antibiotic
    Prescription only

    Ceftriaxone is one of the most commonly used antibiotics because of its low risk for side effects and its ability to treat several types of bacterial infections. Ceftriaxone is an injection given either into the veins or into the muscle, so it's used most often in the hospital or a clinic setting (e.g., nursing home, provider's office). But it can also be used at home in certain situations. The dosage depends on the type and severity of your infection, but it's usually given once per day. If you have a penicillin allergy, you might still be able to receive ceftriaxone depending on your reaction to penicillin.

  • Indications of Cephalexin vs. Ceftriaxone

    Indications for
    •Respiratory tract infections (e.g., strep throat)
    •Ear infections
    •Skin infections (e.g., cellulitis)
    •Bone infections
    •Urinary tract infections (UTIs)
    •Reproductive system infections (e.g., prostatitis)
    Indications for
    •Lower respiratory tract infections (e.g., pneumonia, bronchitis)
    •Ear infections
    •Stomach infections
    •Urinary tract infections (UTIs)
    •Skin infections (e.g., cellulitis)
    •Bone and joint infections
    •Bloodstream infections
    •Meningitis
    •Gonorrhea
    •Pelvic inflammatory disease (PID)
    •Preventing infection from surgery

  • Pros and Cons of Cephalexin vs. Ceftriaxone

    Pros and Const for Cephalosporin antibiotic
    Pros
    •Treats several common types of bacterial infections
    •Okay for children as young as 1 year old to take
    •Available as a liquid for people who have trouble swallowing pills
    Cons
    •Usually need to take a few times per day
    •Might not be able to take if you're allergic to penicillins or other cephalosporin antibiotics
    •Not recommended for the cold or flu (these are viral illnesses, not bacterial infections)
    Pros and Const for Cephalosporin antibiotic
    Pros
    •Can treat many different types of infections
    •Can use in people with kidney problems
    •Can use in children
    •Typically given once per day
    Cons
    •Must be given by an injection into the veins or into the muscle
    •Sometimes requires twice-daily dosing for more severe infections
    •Not a good choice for treating infections caused by resistant bacteria
    •Might not be the best choice if you've had an allergic reaction to penicillins or other cephalosporin antibiotics

  • Common Side Effects of Cephalexin vs. Ceftriaxone

    Common Side Effects for
    •Diarrhea
    •Nausea
    •Vomiting
    •Indigestion
    •Stomach pain
    Common Side Effects for
    •Side effects aren't common. See Other Side Effects.

  • Warnings of Cephalexin vs. Ceftriaxone

    Common Side Effects for
    •Allergic reactions
    •Diarrhea from Clostridioides difficile infection
    •Seizures
    •Higher risk of bleeding
    •Possible development of drug-resistant bacteria
    Common Side Effects for
    •Allergic reactions
    •Avoid administration with calcium-containing medications
    •Nervous system side effects
    •Diarrhea from Clostridioides difficile infection
    •Low red blood cell count (hemolytic anemia)
    •Development of drug-resistant bacteria

  • Prices with our coupons for Cephalexin vs. Ceftriaxone

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