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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
An inner ear infection or otitis interna is caused by viruses or bacteria and can occur in both adults and children. An inner ear infection can cause symptoms and signs, for example, a severe ear, dizziness, vertigo, nausea and vomiting, and vertigo. An inner ear infection also may cause inflammation of the inner ear or labyrinthitis. Inner ear infections are not contagious; however, the bacteria and viruses that cause the infection can be transmitted to other people. Good hygiene practices will help decrease the chances of the infection spreading to others. Inner ear infection symptoms and signs like ear pain and nausea may be relieved with home remedies or over-the-counter (OTC) medication. Some inner ear infections will need to be treated and cured with antibiotics or prescription pain or antinausea medication.
Laryngitis is an inflammation of the voice box (vocal cords). The most common cause of acute laryngitis is an infection, which inflames the vocal cords. Symptoms may vary from the degree of laryngitis and age of the person (laryngitis in infants and children is more commonly caused by croup).
Urinary Tract Infection (UTI)
A urinary tract infection (UTI) is an infection of the bladder, kidneys, ureters, or urethra. E. coli, a type of bacteria that lives in the bowel and near the anus, causes most UTIs. UTI symptoms include pain, abdominal pain, mild fever, urinary urgency, and frequency. Treatment involves a course of antibiotics.
Sore Throat Home Remedies
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Boils (Skin Abscesses)
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Middle Ear Infection (Otitis Media)
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Ear Infection Home Treatment
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Group B strep are bacteria called Streptococcus agalactiae that may sometimes cause infections both in a pregnant woman and her baby. Symptoms include fever, seizures, heart rate abnormalities, breathing problems, and fussiness. Intravenous antibiotics are used to treat group B strep infections.
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Is Strep Throat Contagious?
Strep throat is caused by group A streptococcus bacteria. Incubation period for strep throat is 1-5 days after exposure. If strep throat is treated with antibiotics, it is no longer contagious after 24 hours; if it is not treated with antibiotics, it is contagious for 2-3 weeks. Symptoms include fever, sore throat, tonsillitis, white spots or patches on the tonsils, and nausea and vomiting. Diagnosis of strep throat is performed through a rapid strep test.
Is Tonsillitis Contagious?
Tonsillitis is a common infection, especially in kids. Tonsillitis is caused by viruses and bacteria like the flu and herpes simplex virus, and Streptococcus bacteria. These viruses and bacterium are spread person to person. Symptoms of tonsillitis are a yellow or white coating on the tonsils, throat pain, pain when swallowing, and hoarseness.
An abscessed tooth is an infection within a tooth that has spread to the root. Symptoms of an abscessed tooth may include pain, swelling, tenderness, redness, and the presence of a pus-filled lesion on the gum. A dental professional diagnoses an abscessed tooth and dental X-rays may be required. An abscessed tooth is treated with a root canal.
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.
Pneumonia is inflammation of the lungs caused by fungi, bacteria, or viruses. Symptoms and signs include cough, fever, shortness of breath, and chills. Antibiotics treat pneumonia, and the choice of the antibiotic depends upon the cause of the infection.
Bronchitis is inflammation of the airways in the lung. Acute bronchitis is short in duration (10-20 days) in comparison with chronic bronchitis, which lasts for months to years. Causes of acute bronchitis include viruses and bacteria, which means it can be contagious. Acute bronchitis caused by environmental factors such as pollution or cigarette smoke is not contagious. Common symptoms for acute bronchitis include nasal congestion, cough, headache, sore throat, muscle aches, and fatigue. Acute bronchitis in children also my include runny nose, fever, and chest pain. Treatment for acute bronchitis are OTC pain relievers, cough suppressants (although not recommended in children), and rest. Infrequently antibiotics may be prescribed to treat acute bronchitis.
Is Sore Throat (Pharyngitis) Contagious?
The medical term for a sore throat is pharyngitis. There are many causes of a sore throat such as medications, diseases (GERD, cancer, AIDS), infections (Streptococcus or strep, mononucleosis), allergies, and smoking. Symptoms are a red, swollen throat; fever, and swollen lymph nodes. Treatment for sore throat depends on the cause.
Chronic bronchitis is a cough that occurs daily with production of sputum that lasts for at least 3 months, 2 years in a row. Causes of chronic bronchitis include cigarette smoking, inhaled irritants, and underlying disease processes (such as asthma, or congestive heart failure). Symptoms include cough, shortness of breath, and wheezing. Treatments include bronchodilators and steroids. Complications of chronic bronchitis include COPD and emphysema.
Group A streptococcal infections are caused by group A Streptococcus, a bacteria that causes a variety of health problems, including strep throat, impetigo, cellulitis, erysipelas, and scarlet fever. There are more than 10 million group A strep infections each year.
Scarlet Fever (Scarlatina)
Scarlet fever, a bacterial infection caused by group A Streptococcus bacteria, causes symptoms and signs such as fever, rash with a sandpaper-like texture, and sore throat. Oral penicillin is the standard treatment for scarlet fever, or scarlatina.
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Urinary tract infections (UTIs) are very common in children. Symptoms and signs include fever and abdominal pain. Associated symptoms and signs include flank pain, vomiting, and blood in the urine. Treatment for a UTI involves antibiotic therapy.
Are Boils Contagious?
A boil is a hair follicle that has been infected with bacteria. Boils can spread if a person's boil touches another person. Treatment typically involves draining the boil and using topical and/or oral antibiotics to eliminate the bacteria inside the boil.
What Is the Most Common Cause of Septic Arthritis in Kids?
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Bronchiolitis is an illness caused by a variety of viruses that is most common during the winter season. Bronchiolitis symptoms are nasal congestion and moderate nasal discharge accompanied by mild to severe pulmonary distress. Bronchiolitis usually can be treated at home. Some patients may require hospitalization.
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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