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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.
Latest Skin News
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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Tonsillitis is a contagious infection with symptoms of bad breath, snoring, congestion, headache, hoarseness, laryngitis, and coughing up blood. Tonsillitis can be caused acute infection of the tonsils, and several types of bacteria or viruses (for example, strep throat or mononucleosis). There are two types of tonsillitis, acute and chronic. Acute tonsillitis lasts from one to two weeks while chronic tonsillitis can last from months to years. Treatment of tonsillitis and adenoids include antibiotics, over-the-counter medications, and home remedies to relieve pain and inflammation, for example, salt water gargle, slippery elm throat lozenges, sipping warm beverages and eating frozen foods (ice cream, popsicles), serrapeptase, papain, and andrographism Some people with chronic tonsillitis may need surgery (tonsillectomy or adenoidectomy).
Boils (Skin Abscesses)
A boil is a skin abscess, a collection of pus localized deep in the skin. There are several different types of boils. Among them are the following: furuncle or carbuncle, cystic acne, hidradenitis suppurativa, and pilonidal cyst.
Clostridium Difficile Colitis (C. diff, C. difficle Colitis)
Clostridium difficile (C. difficile) is a bacterium, and is one of the most common causes of infection of the colon. C. difficile spores are found frequently in hospitals, nursing homes, extended care facilities, and nurseries for newborn infants.
Diverticulitis (Diverticulosis, Diverticular Disease)
Most people with diverticulosis have few if any symptoms at all. When people do experience signs and symptoms of diverticulosis (diverticular disease) they may include abdominal pain, abdominal cramps, diarrhea, constipation, and bloating. Diverticulitis is a condition in which diverticuli in the colon rupture. The rupture results in infection in the tissues that surround the colon. Treatment methods for diverticulitis includes prescription medications, and in some cases, diverticulitis surgery.
Pneumonia (Symptoms, Causes, Types, Treatment, and Recovery)
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.
Sore throat (throat pain) usually is described as pain or discomfort in the throat area. A sore throat may be caused by bacterial infections, viral infections, toxins, irritants, trauma, or injury to the throat area. Common symptoms of a sore throat include a fever, cough, runny nose, hoarseness, earaches, sneezing, and body aches. Home remedies for a sore throat include warm soothing liquids and throat lozenges. OTC remedies for a sore throat include OTC pain relievers such as ibuprofen or acetaminophen. Antibiotics may be necessary for some cases of sore throat.
Strep Throat (GAS): Treatment and Symptoms
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 include home remedies and OTC medication; however, the only cure for strep throat are antibiotics.
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.
Group B Strep
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.
Middle Ear Infection (Otitis Media)
Middle ear infection (otitis media) is inflammation of the middle ear. There are two forms of this type of ear infection, acute and chronic. Acute otitis media is generally short in duration, and chronic otitis media generally lasts several weeks. Babies, toddlers, and children with a middle ear infection may be irritable, pull and tug at their ears, and experience numerous other symptoms and signs. Treatment depends upon the type of ear infection.
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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.
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Emphysema, Chronic Bronchitis, and Colds
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Folliculitis (Symptoms, Causes, Transmission, Home Treatment, and Cure)
Folliculitis is a skin condition that causes small red bumps to form around the hair follicles. Skin bacteria such as Staphylococcus and Pseudomonas may infect the follicles. Treatment involves over-the-counter bacterial washes, topical antibiotics, and/or topical steroids.
Laryngitis is an inflammation of the voice box (vocal cords). The most common cause of acute laryngitis is infection, which inflames the vocal cords. Symptoms may vary from degree of laryngitis and age of the person (laryngitis in infants and children is more commonly caused by croup). Common symptoms include a "barky" cough, a hoarse cough, fever, cold, runny nose, dry cough, and loss of voice. Chronic laryngitis generally lasts more than three weeks. Causes other than infection include smoking, excess coughing, GERD, and more. Treatment depends on the cause of laryngitis.
Chronic Bronchitis (Symptoms, Causes, Treatment, Remedies)
Chronic bronchitis is a cough that occurs daily with production of sputum that lasts for at least three months, two 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.
Ingrown hairs may be caused by improper shaving, waxing, or blockage of the hair follicle. Symptoms and signs of ingrown hairs include itching, tenderness, and small red pus bumps. Ingrown hairs usually heal on their own, but topical antibiotics, chemical depilatories, and hair-removal laser may be used in the treatment of ingrown hairs.
Urinary Tract Infections in Children
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.
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.
Sore Throat Home Remedies
Natural and home remedies for sore throat symptoms and pain relief include essential oils, licorice gargles, slippery elm leaves, raw garlic, Throat Coat tea, sage, and acupuncture. Typical symptoms of a sore throat include throat pain, coughing, sneezing, fever, and swollen lymph nodes. Sore throats are caused by viral (common cold, flu, mumps), bacterial (tonsillitis, some STDs), toxins, allergens, trauma or injury, or "mechanical causes" (breathing through the mouth).
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.
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.
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.
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. Bronchioitis usually can be treated at home. Some patients may require hospitalization.
Cough: 19 Tips on How to Stop a Cough
Coughing is a reflex that helps a person clear their airways of irritants. There are many causes of an excessive or severe cough including irritants like cigarette and secondhand smoke, pollution, air fresheners, medications like beta blockers and ACE inhibitors, the common cold, GERD, lung cancer, and heart disease.Natural and home remedies to help cure and soothe a cough include stay hydrated, gargle saltwater, use cough drops or lozenges, use herbs and supplements like ginger, mint, licorice, and slippery elm, and don't smoke. Over-the-counter products (OTC)to cure and soothe a cough include cough suppressants and expectorants, and anti-reflux drugs. Prescription drugs that help cure a cough include narcotic medications, antibiotics, inhaled steroids, and anti-reflux drugs like proton pump inhibitors or PPIs, for example, omeprazole (Prilosec), rabeprazole (Aciphex), and pantoprazole (Protonix).
Ear Infection Home Treatment
Infections of the outer, middle, and inner ear usually are caused by viruses. Most outer (swimmer's ear) and middle ear (otitis media) infections can be treated at home with remedies like warm compresses for ear pain relief, tea tree, ginger, or garlic oil drops. Symptoms of an outer ear (swimmer's ear) and middle ear infection include mild to severe ear pain, pus draining from the ear, swelling and redness in the ear, and hearing problems. Middle and inner ear infections may cause fever, and balance problems. Inner ear infections also may cause nausea, vomiting, vertigo, ringing in the ear, and labyrinthitis (inflammation of the inner ear). Most outer and middle ear infections do not need antibiotics. Inner ear infections should be treated by a doctor specializing in ear and hearing problems.
Inner Ear Infection (Symptoms, Signs, Treatments, Home Remedies)
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.
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