sef-a-LEX-in

Commonly used brand name(s)

In the U.S.

• Bio-Cef
• Keflex
• Panixine DisperDose

In Canada

• Novo-Lexin

Available Dosage Forms:

• Tablet
• Capsule
• Tablet for Suspension
• Powder for Suspension

Therapeutic Class: Antibiotic

Pharmacologic Class: 1st Generation Cephalosporin

Uses For cephalexin

Cephalexin is used to treat bacterial infections in many different parts of the body. It belongs to the class of medicines known as cephalosporin antibiotics. It works by killing bacteria or preventing their growth. However, cephalexin will not work for colds, flu, or other virus infections.

cephalexin is available only with your doctor's prescription.

Before Using cephalexin

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For cephalexin, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to cephalexin or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of cephalexin in children.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of cephalexin in the elderly. However, elderly patients are more likely to have age-related kidney problems, which may require caution and an adjustment in the dose for patients receiving cephalexin.

Pregnancy

Pregnancy Category Explanation All Trimesters B Animal studies have revealed no evidence of harm to the fetus, however, there are no adequate studies in pregnant women OR animal studies have shown an adverse effect, but adequate studies in pregnant women have failed to demonstrate a risk to the fetus.

Breast Feeding

Studies in women suggest that this medication poses minimal risk to the infant when used during breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking cephalexin, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using cephalexin with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Warfarin

Using cephalexin with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Cholestyramine
• Metformin

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of cephalexin. Make sure you tell your doctor if you have any other medical problems, especially:

• Colitis (inflammation in gut), history of or
• Diarrhea, severe, history of—Use with caution. May make these conditions worse.

• Kidney disease—Use with caution. Effects may be increased because of slower removal of the medicine from the body.

Proper Use of cephalexin

Take cephalexin only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

Shake the oral liquid well before each use. Measure the medicine with a marked measuring spoon, oral syringe, or medicine cup. The average household teaspoon may not hold the right amount of liquid.

Keep using cephalexin for the full treatment time, even if you feel better after the first few doses. Your infection may not clear up if you stop using the medicine too soon.

Dosing

The dose of cephalexin will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of cephalexin. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For oral dosage forms (capsules or suspension):
  • For infections:
    • Adults and teenagers—The dose is 1000 to 4000 milligrams (mg) per day, taken in divided doses.
    • Children—Use and dose must be determined by your doctor. Dose is based on body weight and must be determined by your doctor. The dose is usually 25 to 100 milligrams (mg) per kilogram (kg) per day, taken in divided doses.

Missed Dose

If you miss a dose of cephalexin, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Store the capsules in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Store the oral liquid in the refrigerator. Throw away any unused medicine after 14 days.

Precautions While Using cephalexin

If your symptoms do not improve within a few days, or if they become worse, check with your doctor.

Cephalexin may cause diarrhea, and in some cases it can be severe. Do not take any medicine or give medicine to your child to treat diarrhea without first checking with your doctor. Diarrhea medicines may make the diarrhea worse or make it last longer. If you have any questions about this or if mild diarrhea continues or gets worse, check with your doctor.

Before you or your child have any medical tests, tell the medical doctor in charge that you are using cephalexin. The results of some tests may be affected by cephalexin.

cephalexin Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

• Diarrhea

Rare

• Abdominal or stomach pain
• blistering, peeling, or loosening of the skin
• chills
• clay-colored stools
• cough
• dark urine
• diarrhea
• dizziness
• fever
• general tiredness and weakness
• headache
• itching
• joint or muscle pain
• light-colored stools
• loss of appetite
• nausea and vomiting
• rash
• red skin lesions, often with a purple center
• red, irritated eyes
• sore throat
• sores, ulcers, or white spots in the mouth or on the lips
• unpleasant breath odor
• unusual tiredness or weakness
• upper right abdominal or stomach pain
• vomiting of blood
• yellow eyes or skin

Incidence not known

• Abdominal or stomach cramps or tenderness
• back or leg pains
• , tarry stools
• bleeding gums
• bloating
• blood in the urine or stools
• chest pain
• coughing up blood
• diarrhea, watery and severe, which may also be bloody
• difficulty with breathing or swallowing
• fast heartbeat
• general body swelling
• hives
• increased menstrual flow or vaginal bleeding
• increased thirst
• large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
• loss of appetite
• nosebleeds
• pain
• painful or difficult urination
• pale skin
• paralysis
• pinpoint red spots on the skin
• prolonged bleeding from cuts
• puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• red or , tarry stools
• red or dark brown urine
• shortness of breath
• swollen or painful glands
• tightness in the chest
• unusual bleeding or bruising
• unusual weight loss
• watery or bloody diarrhea
• wheezing

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Incidence not known

• Acid or sour stomach
• anxiety
• belching
• burning feeling in the chest or stomach
• difficulty with moving
• dry mouth
• heartburn
• hives or welts
• hyperventilation
• indigestion
• irregular heartbeats
• irritability
• itching of the vagina or genital area
• muscle pain or stiffness
• nervousness
• pain during sexual intercourse
• pain, swelling, or redness in the joints
• redness of the skin
• restlessness
• seeing, hearing, or feeling things that are not there
• shaking
• stomach upset
• trouble with sleeping
• white or brownish vaginal discharge

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

The information contained in the Truven Health Micromedex products as delivered by Drugs.com is intended as an educational aid only. It is not intended as medical advice for individual conditions or treatment. It is not a substitute for a medical exam, nor does it replace the need for services provided by medical professionals. Talk to your doctor, nurse or pharmacist before taking any prescription or over the counter drugs (including any herbal medicines or supplements) or following any treatment or regimen. Only your doctor, nurse, or pharmacist can provide you with advice on what is safe and effective for you.

The use of the Truven Health products is at your sole risk. These products are provided "AS IS" and "as available" for use, without warranties of any kind, either express or implied. Truven Health and Drugs.com make no representation or warranty as to the accuracy, reliability, timeliness, usefulness or completeness of any of the information contained in the products. Additionally, TRUVEN HEALTH MAKES NO REPRESENTATION OR WARRANTIES AS TO THE OPINIONS OR OTHER SERVICE OR DATA YOU MAY ACCESS, DOWNLOAD OR USE AS A RESULT OF USE OF THE THOMSON REUTERS HEALTHCARE PRODUCTS. ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE OR USE ARE HEREBY EXCLUDED. Truven Health does not assume any responsibility or risk for your use of the Truven Health products.

Copyright 2015 Truven Health Analytics, Inc. All Rights Reserved.

Usual Adult Dose for Bacterial Endocarditis Prophylaxis

2 g orally as a single dose one hour before the procedure

Usual Adult Dose for Cystitis

250 mg orally every 6 hours or 500 mg orally every 12 hours for 7 to 14 days

Usual Adult Dose for Otitis Media

500 mg orally every 6 hours for 10 to 14 days

Usual Adult Dose for Pharyngitis

250 mg orally every 6 hours or 500 mg orally every 12 hours

Usual Adult Dose for Skin or Soft Tissue Infection

250 mg orally every 6 hours or 500 mg orally every 12 hours

Usual Adult Dose for Osteomyelitis

500 mg orally every 6 hours
Therapy should be continued for approximately 4 to 6 weeks, depending on the nature and severity of the infection. Chronic osteomyelitis may require an additional one to two months of antibiotic therapy and may benefit from surgical debridement.

Usual Adult Dose for Prostatitis

500 mg orally every 6 hours for 14 days

Usual Adult Dose for Pyelonephritis

500 mg orally every 6 hours for 14 days

Usual Adult Dose for Upper Respiratory Tract Infection

250 to 500 mg orally every 6 hours for 7 to 10 days

Usual Adult Dose for Bacterial Infection

250 to 500 mg orally every 6 hours
Therapy should be continued for approximately 7 to 21 days, depending on the nature and severity of the infection.

Usual Pediatric Dose for Otitis Media

12.5 to 25 mg/kg orally every 6 hours

Usual Pediatric Dose for Pharyngitis

Over 1 year of age:
Streptococcal pharyngitis: 12.5 to 25 mg/kg orally every 12 hours

Usual Pediatric Dose for Skin or Soft Tissue Infection

12.5 to 25 mg/kg orally every 12 hours

Usual Pediatric Dose for Bacterial Endocarditis Prophylaxis

As an alternative in penicillin-allergic patients (non-anaphylactoid type): 50 mg/kg (maximum 2 g) orally once, 1 hour before procedure

Renal Dose Adjustments

CrCl 10 to 40 mL/min: The usual dose should be administered every 8 to 12 hours.
CrCl 9 mL/min or less: The usual dose should be administered every 12 to 24 hours.

Liver Dose Adjustments

Data not available

Dose Adjustments

Infections that are more severe or caused by less susceptible organisms may require dosages up to 4 g per day in divided doses.

Precautions

Serious and occasionally fatal hypersensitivity reactions have been reported with antibiotics. The drug should be discontinued immediately at the first appearance of a skin rash or other signs of hypersensitivity. Severe, acute hypersensitivity reactions may require treatment with epinephrine and other resuscitative measures including oxygen, intravenous fluids, antihistamines, corticosteroids, cardiovascular support and airway management as clinically indicated.

Clostridium difficile associated diarrhea (CDAD) has been reported with almost all antibiotics and may potentially be life-threatening. Therefore, it is important to consider this diagnosis in patients who present with diarrhea following cephalosporin therapy. Mild cases generally improve with discontinuation of the drug, while severe cases may require supportive therapy and treatment with an antimicrobial agent effective against C difficile. Hypertoxin producing strains of C difficile cause increased morbidity and mortality; these infections can be resistant to antimicrobial treatment and may necessitate colectomy.

Patients with phenylketonuria should be aware that some formulations (e.g., dispersible tablets) contain phenylalanine.

Caution is recommended in patients with impaired renal function. Some cephalosporins have been associated with seizures in renally impaired patients with elevated serum concentrations. The drug should be discontinued if seizures occur.

Parenteral cephalosporins should be considered in patients requiring daily cephalexin doses greater than 4 grams.

To reduce the risk of development of drug resistant organisms, antibiotics should only be used to treat or prevent proven or suspected infections caused by bacteria. Culture and susceptibility information should be considered when selecting treatment or, if no data are available, local epidemiology and susceptibility patterns may be considered when selecting empiric therapy. Patients should be advised to avoid missing doses and to complete the entire course of therapy.

Dialysis

Cephalexin is moderately dialyzable (20% to 50%).

Other Comments

In the treatment of beta-hemolytic streptococcal infections, a therapeutic dosage should be administered for at least 10 days.

The adult dosage should be 1 to 4 g per day in divided doses. When using the 333 mg or 750 mg capsules, the total daily dosage of cephalexin should not fall outside this range.

The dispersible tablets for oral suspension should be mixed with 2 teaspoonfuls of water, the patient should drink the entire mixture, then a small amount of water should be used to rinse the container, and the patient should drink this also.

Cephalexin Side Effects