- Bacterial Infections 101 Pictures Slideshow
- Take the Tummy Trouble Quiz
- Hepatitis C Slideshow Pictures
- 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
Daily Health 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.
Multimedia: Slideshows, Images & Quizzes
13 Early Signs & Symptoms of Pregnancy
What are the early signs and symptoms of pregnancy? Can you know before your missed period? Read about nausea and vomiting...
Bacterial Infections 101: Types, Symptoms, and Treatments
Get more information on bacterial skin infections, which bacteria cause food poisoning, sexually transmitted bacteria, and more....
Sore Throat or Strep Throat? How to Tell the Difference
Is this a sore throat or could it be strep throat? Your medical care depends on knowing if you have a viral infection or a...
Ear Infection Symptoms, Causes, and Treatment
Learn about the causes and symptoms of ear infections and how they are diagnosed and treated. Read about treatments such as ear...
Sinus Infection (Sinusitis) Symptoms & Treatment
Sinus infection (sinusitis) symptoms can include headaches, a sore throat, and toothaches. Antibiotics and home remedies can...
Urinary Tract Infection (UTI) Symptoms, Diagnosis, Medication
Bladder infections can be painful and often require medical treatment. Get the latest information on urinary tract infections...
Diverticulitis (Diverticulosis) Symptoms, Diet, Treatment
Diverticulitis (diverticulosis) is a condition in which the diverticulum or diverticula rupture in the colon, causing infection....
Respiratory Illnesses: 13 Types of Lung Infections
Is your cough caused by a cold, flu, pneumonia or something else? Learn causes of respiratory infection like bronchitis,...
Bladder Infections: UTI Causes, Symptoms, Treatments
Urinary tract infections (UTI), including bladder infections, affect women and men, causing UTI symptoms like kidney infection....
What's Bronchitis? Symptoms and Treatments
Is bronchitis contagious? Learn about bronchitis, an inflammation of the lining of the lungs. Explore bronchitis symptoms,...
Ear Infection Quiz: Test Your Medical IQ
Is it possible to prevent ear infections? Take the Ear Infection (Otitis Media) Quiz to learn the risks, causes, symptoms and...
Do I Have Pneumonia? Symptoms & Signs
Pneumonia can be deadly. Take the Pneumonia Quiz on MedicineNet to learn more about this highly contagious, infectious disease.
Strep (Streptococcal) Throat Infection Quiz: Test Your Infectious Disease IQ
Take the Strep (Streptococcal) Throat Infection Quiz to learn about causes, symptoms, treatments, prevention methods, diagnosis,...
What happens within the body when a person develops bronchitis? Take this quick quiz to learn the causes, symptoms, treatments,...
Ear Health Quiz
How loud is too loud? Take this quiz to learn about your ears, how they function, and how to keep them healthy.
Urinary Tract Infection Quiz
How would you know if you had urinary tract infection (UTI)? Take the Urinary Tract Infection in Adult Quiz to learn the causes,...
Picture of Bronchitis
Acute bronchitis usually comes on quickly and gets better after several weeks. See a picture of Acute Bronchitis and learn more...
Picture of Strep Throat
Strep infection often produces a distinct pattern of white patches in the throat and on the tonsils, as well as red swollen...
Picture of Tonsil Stones
Tonsil stones (also called tonsilloliths) form when bacteria and mucus get trapped and calcify in your tonsils' nooks and...
Picture of Tonsils
The tonsils (palatine tonsils) are a pair of soft tissue masses located at the rear of the throat (pharynx). See a picture of the...
Related Disease Conditions
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).
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.
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.
What Are 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.
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.
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).
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).
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.
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.
Impetigo: Treatment, Symptoms, and Complications
Impetigo is a contagious skin infection caused by staph and strep bacteria. There are two types of impetigo: nonbullous and bullous. Symptoms of nonbullous impetigo include small blisters on the nose, face, arms, or legs and possibly swollen glands. Bullous impetigo signs include blisters in various areas, particularly in the buttocks area. Treatment involves gentle cleansing, removing the crusts of popped blisters, and the application of prescription-strength mupirocin antibiotic ointment.
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 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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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?
Septic arthritis can be caused by bacterial, fungal or viral infections. Staphylococcus aureus, a type of bacteria, is the most common cause of septic arthritis in infants. Septic arthritis is a general term for any joint pain caused by infection of the joint.
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.
Treatment & Diagnosis
- Urinary Tract Infection FAQs
- Pneumonia FAQs
- Strep Streptococcal Throat Infection FAQs
- Ear Infection FAQs
- Bronchitis FAQs
- Ear Health FAQs
- Kidney Infections During Pregnancy
- How To Reduce Your Medication Costs
- Pharmacy Visit, How To Get The Most Out of Your Visit
- Indications for Drugs: Approved vs. Non-approved
- Strep Throat Diagnosis & Treatment
- Drugs: The Most Common Medication Errors
- Gonorrhea Treatment Recommendations Update
- Medication Disposal
- Dangers of Mixing Medications
- Drugs: Buying Prescription Drugs Online Safely
- Antibiotics 101
- Generic Drugs, Are They as Good as Brand-Names?
Medications & Supplements
- Penicillin (Antibiotics)
- Cipro, XR (ciprofloxacin) vs. Keflex (cephalexin)
- Drugs: Questions to Ask Your Doctor or Pharmacist about Your Drugs
- Drug Interactions
- Nitrofurantoin vs. Cephalexin
- Keflex vs. Penicillin
- Cefdinir vs. cefixime (Suprax) 3rd Generation Antibiotics
- Suprax (cefixime) vs. Keflex (cephalexin)
- Keflex (cephalexin) Side Effects, Warnings, and Interactions
- Levaquin (levofloxacin) vs. Keflex (cephalexin)
- Suprax (cefixime) vs. Rocephin (ceftriaxone)
Prevention & Wellness
Health Solutions From Our Sponsors
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.