Cephalexin is a common antibiotic used for skin, ear, throat, and urinary infections. It belongs to the cephalosporin family and works by stopping bacteria from building cell walls. Doctors prescribe it when infections are caused by bacteria that respond to this drug. You can usually take it by mouth as pills or liquid.
Typical adult doses range from 250 mg to 500 mg every 6 to 12 hours, depending on the infection. For many simple infections, 500 mg twice a day for seven to ten days is common. Children receive doses based on weight; your healthcare provider will calculate that. Always finish the full course even if you feel better.
Common side effects include nausea, diarrhea, and mild stomach pain. Rash and allergic reactions can happen, especially in people allergic to penicillin. If you notice itching, hives, swollen face, or breathing trouble, stop the drug and seek urgent care. Persistent severe diarrhea could mean a Clostridioides difficile infection and needs prompt attention.
Take cephalexin with or without food, but taking it with food can reduce stomach upset. Measure liquid doses with the syringe the pharmacy gives you. Avoid skipping doses and do not double up; doubling can increase side effects. Tell your provider about kidney problems, since dose adjustments may be needed.
Drug interactions are usually limited, but tell your doctor about blood thinners, probenecid, or metformin. Probenecid can raise cephalexin levels, and kidney issues with other drugs may increase risk. If you are pregnant or breastfeeding, discuss risks and benefits with your provider. Most people tolerate cephalexin well, but individual risk varies.
Keep a list of your allergies and current medicines handy. Store tablets at room temperature and discard expired liquid after the date suggested by the pharmacist. Call your doctor if symptoms worsen, fever returns, or if you develop a new rash. If you suspect a severe allergic reaction, seek emergency help right away.
If you bought cephalexin online, use a reputable pharmacy and confirm a valid prescription. RedBoxRX covers reliable drug info and practical advice so you can use antibiotics safely. Got questions about a prescription or side effects? Contact your healthcare provider for personalized guidance.
Missed doses and resistance: If you miss a dose, take it as soon as you remember unless the next dose is near; then skip the missed dose. Do not save leftover pills for later infections—using leftover antibiotics can promote resistance and may not be the right drug for a new problem. Lab tests like a throat swab or urine culture may be needed to confirm the bacteria causing the infection. If your symptoms don’t improve in 48 to 72 hours, return to your clinician for reassessment. For repeat or complicated infections they may choose a different antibiotic or run more tests. Keep a short record of how long you took antibiotics and any side effects to share during follow up visits. Always.
Jan, 6 2025