Cefuroxime axetil 500 mg is an oral antibiotic used to treat a range of common bacterial infections, including sinus infections, bronchitis flare-ups, urinary tract infections, skin infections, and early Lyme disease. It belongs to the cephalosporin family, a class of antibiotics related to penicillin that kills bacteria by disrupting their ability to build cell walls. The typical dose is 250 to 500 mg taken twice a day for up to 10 days, depending on the type of infection.
Conditions Treated With Cefuroxime Axetil
The FDA has approved cefuroxime axetil tablets for eight specific types of bacterial infections in adults and, in some cases, children:
- Acute bacterial sinusitis: infections of the sinus cavities, specifically the maxillary sinuses behind your cheekbones.
- Acute flare-ups of chronic bronchitis: bacterial worsening of ongoing bronchitis symptoms like cough and mucus production.
- Strep throat and tonsillitis: bacterial infections of the throat and tonsils.
- Uncomplicated urinary tract infections: bladder infections caused by susceptible bacteria like E. coli.
- Uncomplicated skin infections: bacterial infections of the skin and underlying tissue, such as cellulitis or wound infections.
- Early Lyme disease: the stage marked by the expanding “bull’s-eye” rash after a tick bite.
- Uncomplicated gonorrhea: a sexually transmitted infection.
- Ear infections: acute bacterial middle ear infections in children.
The 500 mg strength is the higher of the two available tablet doses. It’s the standard dose prescribed for sinusitis, bronchitis flare-ups, urinary tract infections, and Lyme disease, while throat infections and milder skin infections often call for the 250 mg tablet.
How It Works Against Bacteria
Cefuroxime is a second-generation cephalosporin, which means it has a broader reach than older antibiotics in the same family. It works by interfering with the proteins bacteria need to construct and maintain their cell walls. Without an intact wall, the bacterial cell swells and bursts.
This mechanism makes cefuroxime effective against a wide variety of bacteria. It covers common gram-positive organisms like staph (the non-MRSA type) and strep, as well as gram-negative bacteria like E. coli, Klebsiella, and Haemophilus influenzae. Notably, it works against strains of Haemophilus that have developed resistance to ampicillin, a common older antibiotic. It also has some activity against anaerobic bacteria, the kind that thrive in low-oxygen environments like deep wound infections.
Lyme Disease Treatment
Cefuroxime axetil is one of the recommended antibiotics for early Lyme disease, the stage when the characteristic rash appears. The CDC recommends 500 mg twice daily for 14 days in adults. For children, the dose is weight-based, up to a maximum of 500 mg per dose.
It serves as an alternative for people who can’t take the first-line Lyme treatment (doxycycline), such as pregnant women or young children. When multiple effective treatment durations exist, shorter courses are generally preferred to reduce the risk of side effects like diarrhea and to limit antibiotic resistance.
How to Take It
Cefuroxime axetil tablets are taken twice a day, usually for 7 to 14 days depending on the infection. Finishing the full course matters, even if you feel better after a few days, because stopping early gives surviving bacteria a chance to rebound and potentially develop resistance.
Taking the tablet with food makes a meaningful difference in how much of the drug your body absorbs. When taken on an empty stomach, only about 37% of the medication reaches your bloodstream. With food, that number jumps to 52%. That said, clinical trials showed that treatment outcomes were similar regardless of whether patients ate with the medication, so missing a meal isn’t a reason to skip a dose.
If you take antacids or acid-reducing medications, be aware that they can lower cefuroxime absorption. These drugs reduce stomach acid, which the tablet relies on for proper breakdown. If you need both medications, spacing them apart can help.
Common Side Effects
Most people tolerate cefuroxime axetil well. The side effects that do occur tend to involve the digestive system: nausea, diarrhea, and stomach discomfort are the most frequently reported. This happens because the antibiotic doesn’t distinguish perfectly between harmful bacteria and the helpful bacteria in your gut. Taking the medication with food can ease stomach-related side effects while also improving absorption.
Less common reactions include headache, dizziness, and vaginal yeast infections (since killing off normal bacteria can allow yeast to overgrow). Allergic reactions like rash or hives are possible but uncommon. Severe allergic reactions are rare.
Penicillin Allergy and Cross-Reactivity
Because cephalosporins and penicillins share a similar chemical structure, there’s a concern about cross-reactivity in people with penicillin allergies. For second-generation cephalosporins like cefuroxime, the estimated cross-reactivity rate is up to 10%, though some sources put the real-world risk lower. For comparison, newer third-generation cephalosporins carry a cross-reactivity risk of only about 2 to 3%.
If you’ve had a mild reaction to penicillin (like a rash), your prescriber may still consider cefuroxime appropriate with monitoring. If you’ve ever had a severe allergic reaction to penicillin, such as throat swelling, difficulty breathing, or anaphylaxis, cephalosporins are typically avoided entirely.
What Cefuroxime Does Not Treat
Cefuroxime axetil only works against bacteria. It has no effect on viral infections like the common cold, flu, or most cases of acute bronchitis. Taking antibiotics for viral illnesses won’t help you recover faster and contributes to antibiotic resistance.
It’s also not effective against MRSA (methicillin-resistant staph infections) or other bacteria that have developed resistance to cephalosporins. Your provider may order a culture or sensitivity test for certain infections to confirm the bacteria will respond to cefuroxime before prescribing it.