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- What is Keflex (cephalexin) and what is it used for?
- What are the side effects of Keflex (cephalexin)?
- What is the dosage for Keflex (cephalexin)?
- Which drugs or supplements interact with Keflex (cephalexin)?
- Is Keflex (cephalexin) safe to take if I'm pregnant or breastfeeding?
- What else should I know about Keflex (cephalexin)?
What is Keflex (cephalexin) and what is it used for?
Cephalexin belongs to a class of antibiotics called cephalosporins. They are similar to penicillin in action and side effects. They stop or slow the growth of bacterial cells by preventing bacteria from forming the cell wall that surrounds each cell. The cell wall protects bacteria from the external environment and keeps the contents of the cell together, and without a cell wall, bacteria are not able to survive. Bacteria that are susceptible to cephalexin include Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, E. coli and several others. Cephalexin was approved by the FDA in January 1971.
Cephalexin is used to treat infections caused by bacteria that are susceptible to the effects of cephalexin. Common infections that cephalexin is used for include:
What are the side effects of Keflex (cephalexin)?
The most common side effects of cephalexin are:
- abdominal pain,
- skin rash,
- abnormal liver tests, and
Individuals who are allergic to penicillin may also be allergic to cephalexin. Serious but rare reactions include seizures, severe allergic reactions (anaphylaxis), and low platelet or red blood cell count.
Cephalexin, like almost all antibiotics, may cause mild or severe cases of pseudomembranous colitis, a mild to severe inflammation of the colon. Antibiotics, including cephalexin alter the types of bacteria in the colon and permit overgrowth of a bacterium called Clostridium difficile. Studies indicate that toxins produced by Clostridium difficile are a primary cause of pseudomembranous colitis.
What is the dosage for Keflex (cephalexin)?
- The dose of cephalexin for adults is 1 to 4 grams in divided doses.
- The usual adult dose is 250 mg every 6 hours.
- Some infections may be treated with 500 mg every 12 hours.
- Children are treated with 25-100 mg/kg/day in divided doses.
- The dosing interval may be every 6 or 12 hours depending on the type and seriousness of the infection.
Which drugs or supplements interact with Keflex (cephalexin)?
Is Keflex (cephalexin) safe to take if I'm pregnant or breastfeeding?
What else should I know about Keflex (cephalexin)?
- Cephalexin is available in generic form. You need a prescription to obtain cephalexin.
- Keflex is the brand name available for cephalexin in the US.
- Cephalexin is available as:
- Tablets of 250 and 500 mg.
- Capsules: 250, 500 and 750 mg.
- Powder for Suspension: 125 and 250 mg/5 ml.
- Cephalexin tablets and capsules should be stored at room temperature, 15 C to 30 C (59 F to 86 F). Suspensions should be refrigerated and discarded 14 days after they have been prepared from the powder.
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Keflex (cephalexin) is a prescription antibiotic used for treating middle ear infections (otitis media), tonsillitis, laryngitis, pneumonia, urinary tract infections (UTIs), skin infections, bone infections, throat infections, bronchitis, and bone infections. Review side effects, drug interactions, storage, dosage, and pregnancy safety.
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Inner Ear Infection
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Group B Strep
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Is Tonsillitis Contagious?
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Strep throat is a bacterial infection of the throat. Signs and symptoms of strep throat include headache, nausea, vomiting, sore throat, and fever. Strep throat symptoms in infants and children are different than in adults. Strep throat is contagious and is generally passed from person to person. Treatment for strep throat symptoms includes home remedies and OTC medication; however, the only cure for strep throat are antibiotics.
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Is Sore Throat (Pharyngitis) Contagious?
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Are Boils Contagious?
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Emphysema, Chronic Bronchitis, and Colds
If you have a COPD such as emphysema, avoiding chronic bronchitis and colds is important to avoid a more severe respiratory infection such as pneumonia. Avoiding cigarette smoking, practice good hygeine, stay away from crowds, and alerting your healthcare provider if you have a sinus infection or cold or cough that becomes worse. Treatment options depend upon the severity of the emphysema, bronchitis, or cold combination.
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