- Bacterial Infections 101 Pictures Slideshow
- Take the Tummy Trouble Quiz
- Hepatitis C Slideshow Pictures
- What is cephalexin, and how does it work (mechanism of action)?
- Is cephalexin available as a generic drug?
- What are the side effects of cephalexin?
- What is the dosage for cephalexin?
- Which drugs or supplements interact with cephalexin?
- Is cephalexin safe to take if I'm pregnant or breastfeeding?
- What else should I know about cephalexin?
What is cephalexin, and how does it work (mechanism of action)?
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 for treating
- genital and urinary tract infections,
- bone infections,
- ear infections,
- skin and skin structure infections,
- respiratory infections,
- and bladder infections.
What are the side effects of 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.
Quick GuideSymptoms of Mono: Infectious Mononucleosis Treatment
What is the dosage for 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 cephalexin?
: Cephalexin may reduce the effect of BCG and typhoid vaccines. Cephalexin should not be combined with BCG or typhoid vaccine unless there are no other options.
Is cephalexin safe to take if I'm pregnant or breastfeeding?
NURSING MOTHERS: Cephalexin is excreted in breast milk. Cephalexin should be used with caution or stopped when breastfeeding.
What else should I know about cephalexin?
Do I need a prescription for cephalexin?
Yes, a prescription is needed.
Is cephalexin available as a generic drug?
GENERIC AVAILABLE: Yes
What brand names are available for cephalexin?
What preparations of cephalexin are available?
- Tablets: 250 and 500 mg.
- Capsules: 250, 500 and 750 mg.
- Powder for Suspension: 125 and 250 mg/5 ml.
How should I keep cephalexin stored?
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.
Reference: FDA Prescribing Information
- the middle ear,
- larynx (laryngitis),
- urinary tract,
- and bronchi (bronchitis).
Multimedia: Slideshows, Images & Quizzes
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,...
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 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...
Sore Throat or Strep Throat? How to Tell the Difference
Explore the types and causes of a sore throat through pictures, including strep throat, and learn how to find relief from that...
Early Signs & Symptoms of Pregnancy
Read about early signs and symptoms of pregnancy such as nausea and vomiting (morning sickness), bloating, tender breasts, and...
Diverticulitis (Diverticulosis) Symptoms, Diet, Treatment
Diverticulitis (diverticulosis) is a condition in which the diverticulum or diverticula rupture in the colon causing infection....
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...
Related Disease Conditions
Laryngitis is an inflammation of the voice box (vocal cords). The most common cause of acute laryngitis is infection, which...
Jock itch is an itchy red rash that appears in the groin area. The rash may be caused by a bacterial or fungal infection. People...
Sore throats are generally described as pain or discomfort in the throat area. A sore throat may be caused by: bacterial...
Urinary Tract Infections (UTIs)
A urinary tract infection (UTI) is an infection of the bladder, kidneys, ureters, or urethra. E. coli, a type of bacteria that...
Bronchitis is inflammation of the airways in the lung. Acute bronchitis is is short in duration (10 to 20 days) in comparison...
Tonsillitis is a contagious infection with symptoms such as: Bad...
Impetigo is a contagious skin infection caused by staph and strep bacteria. There are two types of impetigo: nonbullous and...
Pneumonia is inflammation of the lungs caused by fungi, bacteria, or viruses. Symptoms and signs include cough, fever, shortness...
Folliculitis is a skin condition that causes small red bumps to form around the hair follicles. Skin bacteria such as...
Diverticulitis (Diverticulosis, Diverticular Disease)
Most people with diverticulosis have few if any symptoms at all. When people do experience signs and symptoms of diverticulosis...
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...
Strep Throat (Treatment, Causes, Home Remedies)
Strep throat is a bacterial infection of the throat. Signs and symptoms of strep throat include headache, nausea,...
Ear Infection (Otitis Media)
Middle ear infection or inflammation (otitis media) is inflammation of the middle ear. There are two forms of this type of ear...
Urinary Tract Infections in Children
Urinary tract infections (UTIs) are very common in children. Symptoms and signs include fever and abdominal pain. Associated...
Scarlet Fever (Scarlatina)
Scarlet fever, a bacterial infection caused by group A Streptococcus bacteria, causes symptoms and signs such as fever, rash with...
Clostridium Difficile Colitis (Antibiotic-Associated Colitis, C. difficile colitis)
Clostridium difficile (C. difficile) is a bacterium, and is one of the most common causes of infection of the colon. C. difficile...
Ingrown hairs may be caused by improper shaving, waxing, or blockage of the hair follicle. Symptoms and signs of ingrown hairs...
Chronic bronchitis is a cough that occurs daily with production of sputum that lasts for at least three months, two years in a...
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...
Treatment & Diagnosis
- Urinary Tract Infection FAQs
- Pneumonia FAQs
- Strep Streptococcal Throat Infection FAQs
- Ear Infection FAQs
- Antibiotics 101
- How To Reduce Your Medication Costs
- Pharmacy Visit, How To Get The Most Out of Your Visit
- Indications for Drugs: Approved vs. Non-approved
- Generic Drugs, Are They as Good as Brand-Names?
- Drugs: Buying Prescription Drugs Online Safely
- Gonorrhea Treatment Recommendations Update
- Medication Disposal - What to Do with Old or Unusable Medication
- Dangers of Mixing Medications
- Kidney Infection in Pregnancy
- Drugs: The Most Common Medication Errors
- Strep Throat Diagnosis & Treatment
Medications & Supplements
Prevention & Wellness
Daily Health News
Infectious Disease Resources
Subscribe to MedicineNet's General Health Newsletter
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.
Top cephalexin Related ArticlesComplete List
Adenoids and Tonsils
Tonsillitis is a contagious infection with symptoms such as:
- Bad breath
- 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), chronic tonsillitis, and peritonsillar abscess. Treatment of tonsillitis and adenoids include antibiotics and other medications depending on the cause, symptom relief, and in some cases, surgery (tonsillectomy or adenoidectomy ).
Ear Infection SlideshowLearn about the causes and symptoms of ear infections and how they are diagnosed and treated. Read about treatments such as ear tubes and antibiotics, which could prevent future ear infections.
Bronchitis is inflammation of the airways in the lung. Acute bronchitis is is short in duration (10 to 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,
- sore throat,
- muscle aches, and
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.
Diverticulitis SlideshowDiverticulitis (diverticulosis) is a condition in which the diverticulum or diverticula rupture in the colon causing infection. Change in diet and medical treatments such as antibiotics and surgery can ease the symptoms of diverticulitis (diverticulosis).
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,
- constipation, and
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.
Pregnancy SymptomsRead about early signs and symptoms of pregnancy such as nausea and vomiting (morning sickness), bloating, tender breasts, and more. Explore first trimester symptoms.
FolliculitisFolliculitis 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.
ImpetigoImpetigo 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.
Jock ItchJock itch is an itchy red rash that appears in the groin area. The rash may be caused by a bacterial or fungal infection. People with diabetes and those who are obese are more susceptible to developing jock itch. Antifungal shampoos, creams, and pills may be needed to treat fungal jock itch. Bacterial jock itch may be treated with antibacterial soaps and topical and oral antibiotics.
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,
- 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.
Pneumonia FactsPneumonia 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.
Do I Have Pneumonia?Pneumonia can be deadly. Take the Pneumonia Quiz on MedicineNet to learn more about this highly contagious, infectious disease.
Sore Throat (Pharyngitis)Sore throats are generally described as pain or discomfort in the throat area. A sore throat may be caused by:
- bacterial infections,
- viral infections,
- trauma, or
- injury to the throat area.
Sore Throat SlideshowExplore the types and causes of a sore throat through pictures, including strep throat, and learn how to find relief from that raw, scratchy feeling.
Strep Throat QuizTake the Strep (Streptococcal) Throat Infection Quiz to learn about causes, symptoms, treatments, prevention methods, diagnosis, and complications of this common infectious disease.
Tonsil Stones PictureTonsil stones (also called tonsilloliths) form when bacteria and mucus get trapped and calcify in your tonsils' nooks and crannies, leaving a hard piece of matter and a bad taste in your throat. See a picture of Tonsil Stones and learn more about the health topic.
Urinary Tract InfectionA 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.
Urinary Tract Infection QuizHow would you know if you had urinary tract infection (UTI)? Take the Urinary Tract Infection in Adult Quiz to learn the causes, symptoms, and treatments for infection that can affect your kidneys, ureters, bladder, and urethra.