- What is cephalexin?
- Important information
- Before taking this medicine
- How should I take cephalexin?
- What happens if I miss a dose?
- What happens if I overdose?
- What should I avoid while taking cephalexin?
- Cephalexin side effects
- What other drugs will affect cephalexin?
- Further information
- More about cephalexin
- Using Keflex to Treat Urinary Tract Infections
- Hypersensitivity Reactions
- Clostridium Difficile-Associated Diarrhea
- Direct Coombs’ Test Seroconversion
- Seizure Potential
- Prolonged Prothrombin Time
- Development Of Drug-Resistant Bacteria
- Nonclinical Toxicology
- Carcinogenesis, Mutagenesis, Impairment Of Fertility
- Use In Specific Populations
- Nursing Mothers
- Pediatric Use
- Geriatric Use
- Renal Impairment
- About cefalexin
- Before taking cefalexin
- How to take cefalexin
- Getting the most from your treatment
- Can cefalexin cause problems?
- How to store cefalexin
- Important information about all medicines
- Cephalexin: What It Is and How It Can Help Your Dog
- What Dog Diseases Are Treated With Cephalexin?
- Side Effects of Cephalexin in Dogs
- Cephalexin vs Amoxicillin: Main Differences and Similarities
- Cephalexin vs Amoxicillin Side by Side Comparison
- How does this medication work? What will it do for me?
- What form(s) does this medication come in?
- How should I use this medication?
- Who should NOT take this medication?
- What side effects are possible with this medication?
- Are there any other precautions or warnings for this medication?
- What other drugs could interact with this medication?
Generic Name: cephalexin (sef a LEX in)
Brand Names: Daxbia, Keflex
Medically reviewed by Kaci Durbin, MD Last updated on Dec 12, 2018.
- Side Effects
What is cephalexin?
Cephalexin is a cephalosporin (SEF a low spor in) antibiotic. It works by fighting bacteria in your body.
Cephalexin is used to treat infections caused by bacteria, including upper respiratory infections, ear infections, skin infections, urinary tract infections and bone infections.
Cephalexin may also be used for purposes not listed in this medication guide.
You should not use this medicine if you are allergic to cephalexin or to similar antibiotics, such as Ceftin, Cefzil, Omnicef, and others. Tell your doctor if you are allergic to any drugs, especially penicillins or other antibiotics, or if you have kidney or liver disease, a stomach or intestinal disorder such as colitis, diabetes, or if you are malnourished.
Take cephalexin for the entire length of time prescribed by your doctor. Your symptoms may get better before the infection is completely treated. Cephalexin will not treat a viral infection such as the common cold or flu.
Before taking this medicine
Do not use this medicine if you are allergic to cephalexin or to other cephalosporin antibiotics, such as:
To make sure cephalexin is safe for you, tell your doctor if you have:
an allergy to any drugs (especially penicillins);
kidney disease; or
a history of intestinal problems, such as colitis; or
a medical condition that requires blood-thinners
The liquid form of cephalexin may contain sugar. This may affect you if you have diabetes.
Cephalexin is not expected to be harmful to an unborn baby. Tell your doctor if you are pregnant.
Cephalexin can pass into breast milk. Tell your doctor if you are breast-feeding a baby.
How should I take cephalexin?
Take cephalexin exactly as it was prescribed for you. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.
Do not use cephalexin to treat any condition that has not been checked by your doctor.
Shake the oral suspension (liquid) well just before you measure a dose. Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.
Use this medicine for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Skipping doses may also increase your risk of further infection that is resistant to antibiotics. Cephalexin will not treat a viral infection such as the flu or a common cold.
Do not share cephalexin with another person, even if they have the same symptoms you have.
This medication can cause you to have unusual results with certain medical tests. Tell any doctor who treats you that you are using cephalexin.
Store the tablets and capsules at room temperature away from moisture, heat, and light.
Store the liquid medicine in the refrigerator. Throw away any unused liquid after 14 days.
What happens if I miss a dose?
Take cephalexin exactly as it was prescribed for you. Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
Overdose symptoms may include nausea, vomiting, stomach pain, diarrhea, and blood in your urine.
What should I avoid while taking cephalexin?
Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, call your doctor. Do not use anti-diarrhea medicine unless your doctor tells you to.
Cephalexin side effects
Get emergency medical help if you have signs of an allergic reaction to cephalexin: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have:
severe stomach pain, diarrhea that is watery or bloody;
jaundice (yellowing of the skin or eyes);
easy bruising, unusual bleeding (nose, mouth, vagina, or rectum), purple or red pinpoint spots under your skin;
little or no urination;
agitation, confusion, hallucinations; or
severe skin reaction–fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.
Common cephalexin side effects may include:
dizziness, feeling tired;
headache, joint pain; or
vaginal itching or discharge.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
What other drugs will affect cephalexin?
Metformin, probenecid, and blood-thinners may all interact with cephalexin. Other drugs may also interact with cephalexin, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.
Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use cephalexin only for the indication prescribed.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Copyright 1996-2020 Cerner Multum, Inc. Version: 9.01.
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More about cephalexin
- Side Effects
- During Pregnancy or Breastfeeding
- Dosage Information
- Patient Tips
- Drug Images
- Drug Interactions
- Compare Alternatives
- Support Group
- Pricing & Coupons
- En Español
- 342 Reviews
- Drug class: first generation cephalosporins
- Cephalexin Capsules and Tablets
- Cephalexin Suspension
- Cephalexin (Advanced Reading)
Other brands: Keflex, Biocef
- Cephalexin (AHFS Monograph)
- … +3 more
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Using Keflex to Treat Urinary Tract Infections
Keflex is a brand-name drug that’s also available as the generic drug cephalexin. Keflex belongs to a class of drugs called cephalosporins, which are antibiotics. These drugs are often used to treat infections of the bladder or kidneys.
Keflex is used in adults to treat several types of bacterial infections, including UTIs. It’s available as a capsule you take by mouth. It works by stopping bacterial cells from forming properly.
Common side effects
The more common side effects of Keflex can include:
- upset stomach
Serious side effects
In some cases,Keflex can cause serious side effects. These can include:
Serious allergic reaction
Symptoms can include:
- hives or rash
- trouble breathing or swallowing
- swelling of your lips, tongue, or face
- throat tightness
- a rapid heart rate
Symptoms can include:
- pain or tenderness in your abdomen
- dark urine
- yellowing of your skin or the whites of your eyes
Keflex will kill only certain types of bacteria, so other types may continue to grow and cause other infections. Your doctor can tell you more. Symptoms of infections can include:
- body aches
An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well. Before starting Keflex, tell your doctor about all medications, vitamins, or herbs you’re taking. This can help your doctor prevent possible interactions.
Examples of drugs that can interact with Keflex include probenecid and birth control pills.
Other health conditions of concern
Keflex may not be a good choice if you have certain health conditions. Be sure to discuss your health history with your doctor before they prescribe Keflex or any other drug to treat your UTI. Examples of conditions that could cause problems with Keflex include kidney disease and allergies to penicillin or other cephalosporins.
Pregnancy and breastfeeding
Keflex is a category B pregnancy drug. If you’re pregnant, talk with your doctor to see if this drug is safe for you.
Keflex can pass to a child through breast milk. If you breastfeed your child, talk with your doctor about whether you should stop breastfeeding or if you should take a different drug for your UTI.
Learn more: Side effects, dosage, and interactions for cephalexin (Keflex) “
Included as part of the PRECAUTIONS section.
Allergic reactions in the form of rash, urticaria, angioedema, anaphylaxis, erythema multiforme, Stevens-Johnson syndrome, or toxic epidermal necrolysis have been reported with the use of KEFLEX. Before therapy with KEFLEX is instituted, inquire whether the patient has a history of hypersensitivity reactions to cephalexin, cephalosporins, penicillins, or other drugs. Cross-hypersensitivity among beta-lactam antibacterial drugs may occur in up to 10% of patients with a history of penicillin allergy.
If an allergic reaction to KEFLEX occurs, discontinue the drug and institute appropriate treatment.
Clostridium Difficile-Associated Diarrhea
Clostridium difficile-associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including KEFLEX, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile.
C. difficile produces toxins A and B, which contribute to the development of CDAD. Hypertoxin-producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents.
If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile, and surgical evaluation should be instituted as clinically indicated.
Direct Coombs’ Test Seroconversion
Positive direct Coombs’ tests have been reported during treatment with the cephalosporin antibacterial drugs including cephalexin. Acute intravascular hemolysis induced by cephalexin therapy has been reported. If anemia develops during or after cephalexin therapy, perform a diagnostic work-up for drug-induced hemolytic anemia, discontinue cephalexin and institute appropriate therapy.
Several cephalosporins have been implicated in triggering seizures, particularly in patients with renal impairment when the dosage was not reduced. If seizures occur, discontinue KEFLEX. Anticonvulsant therapy can be given if clinically indicated.
Prolonged Prothrombin Time
Cephalosporins may be associated with prolonged prothrombin time. Those at risk include patients with renal or hepatic impairment, or poor nutritional state, as well as patients receiving a protracted course of antibacterial therapy, and patients receiving anticoagulant therapy. Monitor prothrombin time in patients at risk and manage as indicated.
Development Of Drug-Resistant Bacteria
Prescribing KEFLEX in the absence of a proven or strongly suspected bacterial infection is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.
Prolonged use of KEFLEX may result in the overgrowth of nonsusceptible organisms. Careful observation of the patient is essential. If superinfection occurs during therapy, appropriate measures should be taken.
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Lifetime studies in animals have not been performed to evaluate the carcinogenic potential of cephalexin. Tests to determine the mutagenic potential of cephalexin have not been performed. In male and female rats, fertility and reproductive performance were not affected by cephalexin oral doses up to 1.5 times the highest recommended human dose based upon body surface area.
Use In Specific Populations
Pregnancy Category B
There are no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.
Reproduction studies have been performed on mice and rats using oral doses of cephalexin monohydrate 0.6 and 1.5 times the maximum daily human dose (66 mg/kg/day) based upon body surface area basis, and have revealed no evidence of impaired fertility or harm to the fetus.
Cephalexin is excreted in human milk. Caution should be exercised when KEFLEX is administered to a nursing woman.
The safety and effectiveness of KEFLEX in pediatric patients was established in clinical trials for the dosages described in the dosage and administration section .
Of the 701 subjects in 3 published clinical studies of cephalexin, 433 (62%) were 65 and over. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, and other reported clinical experience has not identified differences in responses between the elderly and younger patients.
This drug is substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection .
KEFLEX should be administered with caution in the presence of impaired renal function (creatinine clearance < 30 mL/min, with or without dialysis). Under such conditions, careful clinical observation and laboratory studies renal function monitoring should be conducted because safe dosage may be lower than that usually recommended .
1. Clinical and Laboratory Standards Institute (CLSI). Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria that Grow Aerobically; Approved Standard – Tenth Edition. CLSI document M07-A10, Clinical and Laboratory Standards Institute, 950 West Valley Road, Suite 2500, Wayne, Pennsylvania 19087, USA, 2015.
2. Clinical and Laboratory Standards Institute (CLSI). Performance Standards for Antimicrobials Susceptibility Tests; Twenty-Fifth Informational Supplement. CLSI document M100-S25, Clinical and Laboratory Standards Institute, 950 West Valley Road, Suite 2500, Wayne, Pennsylvania 19087, USA, 2015.
3. Clinical and Laboratory Standards Institute (CLSI). Performance Standards for Antimicrobial Disk Susceptibility Tests; Approved Standard – Twelfth Edition. CLSI document M02-A12, Clinical and Laboratory Standards Institute, 950 West Valley Road, Suite 2500, Wayne, Pennsylvania 19087, USA, 2015.
|Type of medicine||A cephalosporin antibiotic|
|Used for||Treatment (and sometimes prevention) of infection|
|Also called||Cephalexin (in US); Keflex®|
|Available as||Capsules, tablets, and oral liquid medicine|
Cefalexin is a broad-spectrum antibiotic, which means that it is active against a wide variety of germs (bacteria). It is used to treat bacterial infections such as urinary tract infections, skin infections, chest and throat infections, ear infections and dental infections. It is suitable for adults and children and can be taken during pregnancy. Some people who are allergic to penicillin antibiotics may not be able to take cefalexin, so make sure your doctor knows if you have ever had an allergic reaction to any other antibiotic.
Cefalexin treats an infection by killing the bacteria that are causing it.
Before taking cefalexin
Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you (or your child, if appropriate) start taking cefalexin it is important that your doctor knows:
- If you have ever had an allergic reaction to a medicine. It is particularly important that you tell your doctor if you have had a bad reaction to a penicillin or cephalosporin antibiotic.
- If you have any problems with the way your kidneys work.
- If you are pregnant, trying for a baby or breastfeeding. Although cefalexin is not known to be harmful to babies, it is still important that you tell your doctor if you are expecting or breastfeeding a baby.
- If you are taking or using any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.
How to take cefalexin
- Before you start taking cefalexin, read the manufacturer’s printed information leaflet from inside the pack. It will give you more information about the antibiotic and will provide you with a full list of side-effects which you could experience from taking it.
- As a guide, it is usual to take 2-4 doses of cefalexin daily to treat an infection. Your doctor will tell you what dose is right for you (or your child) and the directions for taking it will be printed on the label of the pack to remind you about what the doctor said to you. If you have been given cefalexin liquid medicine to give to your child, please read the directions carefully to make sure that you give the correct amount. Your doctor will tell you how long your course of treatment will last – this is commonly about 5-7 days, although it could be for longer or shorter periods of time than this. It is important that you take cefalexin exactly as your doctor tells you to.
- If you have been prescribed cefalexin to prevent a urinary tract infection from recurring, you are likely to be asked to take just one dose a day. Please take it in the evening. A course of treatment such as this can last for some time.
- Cefalexin can be taken either before or after food, although it may start to work a little sooner if it is taken before food.
- Space the doses evenly throughout the day. Keep taking this medicine until the course is finished unless you are told to stop. It is important to take the full course (even if you feel your infection has cleared up) in order to prevent the infection from coming back.
- If you forget to take a dose, take one as soon as you remember. Try to take the correct number of doses each day but do not take two doses at the same time to make up for a missed dose.
Getting the most from your treatment
- If you are having an operation or any other medical treatment, tell the person carrying out the treatment that you are taking an antibiotic. This is because cefalexin can interfere with the results of some medical tests.
- Some people develop redness and itching in the mouth or vagina (thrush) after taking a course of antibiotics. If after taking cefalexin you think you could have thrush, please speak with your doctor or pharmacist for advice.
- If you are taking the contraceptive ‘pill’ at the same time as an antibiotic, the effectiveness of the ‘pill’ can be reduced if you have a bout of being sick (vomiting) or diarrhoea which lasts for more than 24 hours. If this should happen, ask your doctor or pharmacist for advice about what additional contraceptive precautions to use. There is no need to use additional precautions for any bouts of sickness or diarrhoea which last for less than 24 hours.
- Antibiotics like cefalexin can stop the oral typhoid vaccine from working properly. If you are due to have any vaccinations, please make sure the person treating you knows that you are taking this antibiotic.
Can cefalexin cause problems?
Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the ones associated with cefalexin. You will find a full list in the manufacturer’s information leaflet supplied with the medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.
|Cefalexin side-effects||What can I do if I experience this?|
|Diarrhoea||Drink plenty of water to replace the lost fluids. If the diarrhoea continues for longer than 24 hours, becomes severe, or contains blood, please let your doctor know straightaway|
|Indigestion, stomach ache, feeling sick (nausea)||Stick to simple foods. If you are not already doing so, try taking your doses after meals|
|Thrush||Speak with your doctor or pharmacist for advice|
Important: if you develop an itchy rash, swollen face or mouth, or have difficulty breathing, these can be signs that you are allergic to the antibiotic. Do not take any more doses and speak with your doctor or go to your local accident and emergency department straightaway.
If you experience any other symptoms which you think may be due to the antibiotic, please speak with your doctor or pharmacist for further advice.
How to store cefalexin
- Keep all medicines out of the reach and sight of children.
- Store tablets and capsules in a cool, dry place, away from direct heat and light.
- If you have been given liquid medicine, store it in a refrigerator. It will have been made up freshly by the pharmacy and lasts for 14 days, so please remember to check the expiry date and do not use it after this date.
Important information about all medicines
Do not take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.
This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.
If you buy any medicines, check with a pharmacist that they are safe to take with your other medicines.
If you are having an operation or any dental treatment, tell the person carrying out the treatment which medicines you are taking.
Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.
If you have any questions about this medicine ask your pharmacist.
Cephalexin: What It Is and How It Can Help Your Dog
Cephalexin is one of several antibiotics (medicines that kill bacteria) used to treat a range of bacterial infections in people, dogs, and other animals. Like other antibiotics, it does not work against viral infections.
It belongs to the class of antibiotics known as a first-generation cephalosporin. The drug also goes by the name cefalexin. These are the generic names for a drug that is known by the brand names Keflex, Biocef, and Keftab. It is an oral medication and can be given with or without food. Offering the drug with food, however, can reduce the risk of some of the more common side effects.
Tell your vet if your dog is taking any other kind of drug, including herbal and over-the-counter remedies, or has a medical issue that might rule out cephalexin treatment, including:
- side effects from other drugs
- digestive upset
- kidney disease
- pregnancy, nursing
The World Health Organization includes this drug on its List of Essential Medicines. It is effective against gram-positive and gram-negative bacteria, and it kills these bugs by disrupting the growth of the bacterial cell wall and causing it to rupture.
What Dog Diseases Are Treated With Cephalexin?
Cephalexin is effective against several infections in dogs, including:
- Urinary tract (UTI)
- Skin and soft tissue, such as hotspots and pyoderma
- Respiratory tract
- Ear (otitis)
The drug is considered a broad-spectrum antibiotic, and is effective against several bacteria, including:
- Staphylococcus aureus
- Streptococcus pneumonia
- Haemophilus influenza
- E. coli
- Streptococcus pyogenes
- Klebsiella pneumonia
- Proteus mirabilis
Side Effects of Cephalexin in Dogs
As in humans, antibiotic treatment with drugs like cephalexin are usually well-tolerated. This drug can interact with other medications, including the antibiotic penicillin and some blood thinners. Some side effects to look out for include:
- Skin rashes
If you see any of these side effects, contact your veterinarian.
Cephalexin is available by prescription. All antibiotics should be administered with veterinary supervision, and you must follow your medical professional’s instructions to the letter. Never give your dog antibiotics that have been left over from a prescription for a person or another animal.
|For suspension||Oral||125 mg/5mL|
|For suspension||Oral||250 mg/5mL|
|Powder, for suspension||Oral||125 mg/5mL|
|Powder, for suspension||Oral||250 mg/5mL|
|Powder, for suspension||Oral||125 mg|
|Powder, for suspension||Oral||250 mg|
|Tablet, soluble||Oral||125 mg/1|
|Tablet, soluble||Oral||250 mg/1|
|Powder, for suspension||Oral|
|Cephalexin 250 mg/5ml Suspension 200ml Bottle||32.76USD||bottle|
|Cephalexin 250 mg/5ml Suspension 100ml Bottle||19.66USD||bottle|
|Cephalexin 125 mg/5ml Suspension 200ml Bottle||16.39USD||bottle|
|Cephalexin 125 mg/5ml Suspension 100ml Bottle||15.99USD||bottle|
|Keflex 500 mg capsule||5.75USD||capsule|
|Keflex 500 mg pulvule||4.99USD||each|
|Keflex 750 mg capsule||3.34USD||capsule|
|Cephalexin 500 mg tablet||2.25USD||tablet|
|Keflex 250 mg capsule||2.2USD||capsule|
|Keflex 250 mg pulvule||1.85USD||each|
|Cephalexin 500 mg capsule||1.4USD||capsule|
|Cephalexin 250 mg tablet||1.17USD||tablet|
|Cephalexin 250 mg capsule||0.72USD||capsule|
|Apo-Cephalex 500 mg Tablet||0.47USD||tablet|
|Novo-Lexin 500 mg Capsule||0.47USD||capsule|
|Novo-Lexin 500 mg Tablet||0.47USD||tablet|
|Nu-Cephalex 500 mg Tablet||0.47USD||tablet|
|Apo-Cephalex 250 mg Tablet||0.24USD||tablet|
|Novo-Lexin 250 mg Capsule||0.24USD||capsule|
|Novo-Lexin 250 mg Tablet||0.24USD||tablet|
|Nu-Cephalex 250 mg Tablet||0.24USD||tablet|
|Novo-Lexin 50 mg/ml Suspension||0.14USD||ml|
|Novo-Lexin 25 mg/ml Suspension||0.09USD||ml|
DrugBank does not sell nor buy drugs. Pricing information is supplied for informational purposes only. Patents Not Available
State Solid Experimental Properties Predicted Properties
|Water Solubility||0.297 mg/mL||ALOGPS|
|pKa (Strongest Acidic)||3.45||ChemAxon|
|pKa (Strongest Basic)||7.44||ChemAxon|
|Hydrogen Acceptor Count||5||ChemAxon|
|Hydrogen Donor Count||3||ChemAxon|
|Polar Surface Area||112.73 Å2||ChemAxon|
|Rotatable Bond Count||4||ChemAxon|
|Number of Rings||3||ChemAxon|
|Rule of Five||Yes||ChemAxon|
Predicted ADMET features
|Human Intestinal Absorption||–||0.7537|
|Blood Brain Barrier||–||0.996|
|P-glycoprotein inhibitor I||Non-inhibitor||0.9033|
|P-glycoprotein inhibitor II||Non-inhibitor||0.9921|
|Renal organic cation transporter||Non-inhibitor||0.9485|
|CYP450 2C9 substrate||Non-substrate||0.8011|
|CYP450 2D6 substrate||Non-substrate||0.8308|
|CYP450 3A4 substrate||Non-substrate||0.5289|
|CYP450 1A2 substrate||Non-inhibitor||0.9242|
|CYP450 2C9 inhibitor||Non-inhibitor||0.9251|
|CYP450 2D6 inhibitor||Non-inhibitor||0.9359|
|CYP450 2C19 inhibitor||Non-inhibitor||0.922|
|CYP450 3A4 inhibitor||Non-inhibitor||0.831|
|CYP450 inhibitory promiscuity||Low CYP Inhibitory Promiscuity||0.9303|
|Ames test||Non AMES toxic||0.6834|
|Biodegradation||Not ready biodegradable||0.9812|
|Rat acute toxicity||1.2715 LD50, mol/kg||Not applicable|
|hERG inhibition (predictor I)||Weak inhibitor||0.9971|
|hERG inhibition (predictor II)||Non-inhibitor||0.8686|
ADMET data is predicted using admetSAR, a free tool for evaluating chemical ADMET properties. (23092397)
Mass Spec (NIST) Not Available Spectra
Description This compound belongs to the class of organic compounds known as cephalosporins. These are compounds containing a 1,2-thiazine fused to a 2-azetidinone to for a oxo-5-thia-1-azabicyclooct-2-ene-2-carboxylic acid moiety or a derivative thereof. Kingdom Organic compounds Super Class Organoheterocyclic compounds Class Lactams Sub Class Beta lactams Direct Parent Cephalosporins Alternative Parents N-acyl-alpha amino acids and derivatives / Alpha amino acid amides / Phenylacetamides / Aralkylamines / 1,3-thiazines / Tertiary carboxylic acid amides / Secondary carboxylic acid amides / Amino acids / Azetidines / Thiohemiaminal derivativesMonocarboxylic acids and derivatives / Dialkylthioethers / Carboxylic acids / Azacyclic compounds / Carbonyl compounds / Hydrocarbon derivatives / Monoalkylamines / Organic oxides / Organopnictogen compounds show 9 more Substituents Cephalosporin / N-acyl-alpha amino acid or derivatives / Alpha-amino acid amide / Alpha-amino acid or derivatives / Phenylacetamide / Aralkylamine / Meta-thiazine / Monocyclic benzene moiety / Benzenoid / Tertiary carboxylic acid amideAmino acid or derivatives / Amino acid / Carboxamide group / Azetidine / Secondary carboxylic acid amide / Carboxylic acid / Monocarboxylic acid or derivatives / Carboxylic acid derivative / Azacycle / Thioether / Hemithioaminal / Dialkylthioether / Organic nitrogen compound / Primary aliphatic amine / Organonitrogen compound / Organooxygen compound / Carbonyl group / Primary amine / Hydrocarbon derivative / Organic oxide / Amine / Organopnictogen compound / Organic oxygen compound / Aromatic heteropolycyclic compound show 24 more Molecular Framework Aromatic heteropolycyclic compounds External Descriptors cephalosporin (CHEBI:3534)
Kind Protein Organism Streptococcus pneumoniae Pharmacological action Yes Actions Inhibitor General Function Serine-type d-ala-d-ala carboxypeptidase activity Specific Function Not Available Gene Name pbp3 Uniprot ID Q75Y35 Uniprot Name Penicillin-binding protein 3 Molecular Weight 45209.84 Da
- Williamson R, Hakenbeck R, Tomasz A: In vivo interaction of beta-lactam antibiotics with the penicillin-binding proteins of Streptococcus pneumoniae. Antimicrob Agents Chemother. 1980 Oct;18(4):629-37.
Kind Protein Organism Streptococcus pneumoniae (strain ATCC BAA-255 / R6) Pharmacological action Yes Actions Inhibitor General Function Transferase activity, transferring acyl groups Specific Function Not Available Gene Name pbp2a Uniprot ID Q8DNB6 Uniprot Name Penicillin-binding protein 2a Molecular Weight 80797.94 Da
- Williamson R, Hakenbeck R, Tomasz A: In vivo interaction of beta-lactam antibiotics with the penicillin-binding proteins of Streptococcus pneumoniae. Antimicrob Agents Chemother. 1980 Oct;18(4):629-37.
- Mitsuoka K, Kato Y, Kubo Y, Tsuji A: Functional expression of stereoselective metabolism of cephalexin by exogenous transfection of oligopeptide transporter PEPT1. Drug Metab Dispos. 2007 Mar;35(3):356-62. Epub 2006 Dec 1.
Kind Protein Organism Streptococcus pneumoniae (strain ATCC BAA-255 / R6) Pharmacological action Yes Actions Inhibitor General Function Transferase activity, transferring acyl groups Specific Function Not Available Gene Name pbp1b Uniprot ID Q7CRA4 Uniprot Name Penicillin-binding protein 1b Molecular Weight 89479.92 Da
- Williamson R, Hakenbeck R, Tomasz A: In vivo interaction of beta-lactam antibiotics with the penicillin-binding proteins of Streptococcus pneumoniae. Antimicrob Agents Chemother. 1980 Oct;18(4):629-37.
Kind Protein Organism Streptococcus pneumoniae (strain ATCC BAA-255 / R6) Pharmacological action Yes Actions Inhibitor General Function Not Available Specific Function Penicillin binding Gene Name penA Uniprot ID P0A3M6 Uniprot Name Penicillin-binding protein 2B Molecular Weight 73872.305 Da
Kind Protein Organism Streptococcus pneumoniae (strain ATCC BAA-255 / R6) Pharmacological action Yes Actions Inhibitor General Function Penicillin binding Specific Function Cell wall formation. Gene Name pbpA Uniprot ID Q8DR59 Uniprot Name Penicillin-binding protein 1A Molecular Weight 79700.9 Da
Details1. Serum albumin Kind Protein Organism Humans Pharmacological action No Actions Other/unknown General Function Toxic substance binding Specific Function Serum albumin, the main protein of plasma, has a good binding capacity for water, Ca(2+), Na(+), K(+), fatty acids, hormones, bilirubin and drugs. Its main function is the regulation of the colloid… Gene Name ALB Uniprot ID P02768 Uniprot Name Serum albumin Molecular Weight 69365.94 Da
Kind Protein Organism Humans Pharmacological action Unknown Actions Inhibitor General Function Symporter activity Specific Function Sodium-ion dependent, high affinity carnitine transporter. Involved in the active cellular uptake of carnitine. Transports one sodium ion with one molecule of carnitine. Also transports organic cat… Gene Name SLC22A5 Uniprot ID O76082 Uniprot Name Solute carrier family 22 member 5 Molecular Weight 62751.08 Da
× Details Binding Properties2. Solute carrier family 15 member 1 Kind Protein Organism Humans Pharmacological action Unknown Actions Substrate Inhibitor General Function Proton-dependent oligopeptide secondary active transmembrane transporter activity Specific Function Proton-coupled intake of oligopeptides of 2 to 4 amino acids with a preference for dipeptides. May constitute a major route for the absorption of protein digestion end-products. Gene Name SLC15A1 Uniprot ID P46059 Uniprot Name Solute carrier family 15 member 1 Molecular Weight 78805.265 Da ×
Details Binding Properties3. Solute carrier family 15 member 2 Kind Protein Organism Humans Pharmacological action Unknown Actions Inhibitor General Function Peptide:proton symporter activity Specific Function Proton-coupled intake of oligopeptides of 2 to 4 amino acids with a preference for dipeptides. Gene Name SLC15A2 Uniprot ID Q16348 Uniprot Name Solute carrier family 15 member 2 Molecular Weight 81782.77 Da Kind Protein Organism Humans Pharmacological action Unknown Actions Substrate Inhibitor General Function Sodium-independent organic anion transmembrane transporter activity Specific Function Involved in the renal elimination of endogenous and exogenous organic anions. Functions as organic anion exchanger when the uptake of one molecule of organic anion is coupled with an efflux of one … Gene Name SLC22A6 Uniprot ID Q4U2R8 Uniprot Name Solute carrier family 22 member 6 Molecular Weight 61815.78 Da Kind Protein Organism Humans Pharmacological action Unknown Actions Substrate General Function Monovalent cation:proton antiporter activity Specific Function Solute transporter for tetraethylammonium (TEA), 1-methyl-4-phenylpyridinium (MPP), cimetidine, N-methylnicotinamide (NMN), metformin, creatinine, guanidine, procainamide, topotecan, estrone sulfat… Gene Name SLC47A1 Uniprot ID Q96FL8 Uniprot Name Multidrug and toxin extrusion protein 1 Molecular Weight 61921.585 Da Kind Protein Organism Humans Pharmacological action Unknown Actions Inhibitor General Function Sodium-independent organic anion transmembrane transporter activity Specific Function Plays an important role in the excretion/detoxification of endogenous and exogenous organic anions, especially from the brain and kidney. Involved in the transport basolateral of steviol, fexofenad… Gene Name SLC22A8 Uniprot ID Q8TCC7 Uniprot Name Solute carrier family 22 member 8 Molecular Weight 59855.585 Da ×
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Drug created on June 13, 2005 07:24 / Updated on February 02, 2020 04:23
Cephalexin vs Amoxicillin: Main Differences and Similarities
Cephalexin and amoxicillin are two antibiotic medications that can treat bacterial infections. Both drugs belong to a broad class of antibiotics called beta-lactams. Cephalexin is further categorized as a cephalosporin while amoxicillin is characterized in the penicillin group. Although both drugs are used for similar therapeutic purposes, they have some differences especially in what conditions they treat.
Cephalexin is the generic name for Keflex. It is considered a first generation cephalosporin that works like other beta-lactam antibiotics. Cephalexin exerts its bacterial killing effects by disrupting the ability of bacteria to form cell walls. Without the cell wall, the bacteria cannot survive and replicate.
Cephalexin is indicated to treat respiratory tract infections, ear infections (otitis media), skin infections, bone infections, and urinary tract infections. Cephalexin should only be used to treat these infections when the type of bacteria causing the infection is known to be susceptible to cephalexin.
Cephalexin is available as a generic in 250 mg, 500 mg, and 750 mg oral capsules, 250 and 500 mg oral tablets, and 125 mg/5 mL and 250 mg/5 mL oral suspensions. Dosing is largely variable and dependent on the infection being treated. Total duration of treatment can last up to 2 weeks in some cases.
Amoxicillin is part of a group of beta-lactam antibiotics called penicillins. It works in a similar way as cephalexin by disrupting bacterial cell walls. However, amoxicillin can treat other conditions with different dosing parameters.
Amoxicillin is used to treat ear, nose, and throat infections, lower respiratory tract infections, skin infections, genitourinary infections, and acute uncomplicated gonorrhea infections. Amoxicillin can also be used in combination with other drugs to treat H. pylori infections and duodenal ulcer disease. Like cephalexin, amoxicillin is only recommended if the particular infection is susceptible to it.
Amoxicillin is available as a generic oral capsule with a strength of 250 mg or 500 mg. Amoxicillin can also be taken as an oral suspension, oral tablet, or oral chewable tablet. Like cephalexin, dosing and duration of treatment is variable and determined by your doctor.
Cephalexin vs Amoxicillin Side by Side Comparison
Cephalexin and amoxicillin are two antibiotics that can treat similar illnesses. However, they also have some differences in what they are used for. Other differences can be found in the table below.
|Common Side Effects|
|Is there a generic?|
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|Can I use while planning pregnancy, pregnant, or breastfeeding?|
Cephalexin and amoxicillin can be used to treat a variety of bacterial infections. While they are both part of the broad spectrum family of beta-lactams, they have some differences in how they are used. As a cephalosporin, cephalexin may be preferred for infections such as osteomyelitis, or infections in the bone. On the other hand, amoxicillin may be more appropriate for someone with acute, uncomplicated gonorrhea.
Both medications have similar side effects and drug interactions. For instance, they should not be used with probenecid. Caution should also be exercised when using blood thinners such as warfarin. The most common side effects include diarrhea and nausea for both antibiotics.
Because both medications are renally excreted, dose adjustments need to be made in those with renal impairment. Therefore, It is important to consult with a doctor regarding these antibiotics. Depending on your infection and overall condition, one antibiotic may be preferred over the other.
How does this medication work? What will it do for me?
Cephalexin is an antibiotic that belongs to the family of medications known as cephalosporins. It is used to treat certain types of bacterial infections. Cephalexin is most often used to treat infections of the throat, skin, ear, bladder, respiratory tract, and bone. It works by killing the bacteria causing the infection.
This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.
Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.
Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.
What form(s) does this medication come in?
This medication is available as 500 mg tablets.
How should I use this medication?
The recommended adult dose of cephalexin ranges from 250 mg to 1,000 mg 4 times daily. It can be taken with food or on an empty stomach.
The usual dose of cephalexin for children is based on body weight. The recommended dose is 25 mg to 50 mg per kilogram of body weight each day, divided into 4 equal doses.
Many things can affect the dose of a medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.
Although it may be absorbed more quickly if it is taken on an empty stomach, cephalexin may be taken with food or on an empty stomach. The overall effect is not changed by taking it with food.
The liquid form of this medication should be measured accurately with a medication spoon or oral syringe.
Finish all of this medication, even you start to feel better. This will reduce the chance of the infection returning.
It is important to take this medication exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.
Store the liquid form of this medication in the refrigerator. Do not freeze. The tablets should be stored at room temperature. Protect all forms of this medication from light and moisture, and keep it out of the reach of children.
Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.
Who should NOT take this medication?
Cephalexin should not be taken by anyone who:
- is allergic to cephalexin, any of the cephalosporin antibiotics, or to any of the ingredients of the medication
- is allergic to penicillin (people allergic to penicillin should be monitored by their doctor as they have an increased risk of being allergic to cephalosporin antibiotics)
What side effects are possible with this medication?
Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent. The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.
The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.
Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.
- mild diarrhea
- mild stomach cramps
- sore mouth or tongue
- vaginal itching or discharge
Although most of these side effects listed below don’t happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- abdominal tenderness
- convulsions (seizures)
- decrease in urine output
- hearing loss (young children)
- joint pain
- severe abdominal or stomach cramps and pain
- signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
- skin rash, itching, redness, or swelling
- unusual bleeding or bruising
- unusual tiredness or weakness
Stop taking the medication and seek immediate medical attention if any of the following occur:
- diarrhea (watery and severe; may also be bloody)
- fever that appears after starting the antibiotic
- signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)
- signs of a severe skin reaction (e.g., blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort)
Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.
Are there any other precautions or warnings for this medication?
Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Allergy: Some people who are allergic to penicillin antibiotics also experience allergic reactions to cephalosporins, including cephalexin. Before you take cephalexin, inform your doctor about any previous adverse reactions you have had to medications, especially cephalosporins and penicillins. Contact your doctor at once if you experience signs of an allergic reaction, such as skin rash, itching, difficulty breathing, or swelling of the face and throat.
Antibiotic-associated colitis: This medication, like other antibiotics, may cause a potentially dangerous condition called antibiotic-associated colitis (or pseudomembranous colitis). Symptoms include severe, watery diarrhea that may be bloody. If you notice these symptoms, stop taking cephalexin and contact your doctor as soon as possible.
Bacterial resistance: Misuse of an antibiotic such as cephalexin may lead to the growth of resistant bacteria that will not be killed by the antibiotic. If this happens, the antibiotic may not work for you in the future. Although you may begin to feel better early in your course of treatment with cephalexin, you need to take the full course exactly as directed to finish ridding your body of the infection and to prevent resistant bacteria from taking hold. Do not take cephalexin or other antibiotics to treat a viral infection such as the common cold; antibiotics do not kill viruses, and using them to treat viral infections can lead to the growth of resistant bacteria.
Kidney function: People with severe kidney problems may require a lower dose of cephalexin. People with kidney disease or reduced kidney function should discuss with their doctor how this medication may affect their medical condition, how their medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Liver function: Cephalexin can cause a decrease in liver function, although this happens only occasionally. People with liver disease or reduced liver function should discuss with their doctor how this medication may affect their medical condition, how their medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. If you experience signs of decreasing liver function, such as yellowing of the skin or whites of the eyes, dark urine, or pale stools, contact your doctor as soon as possible.
Overgrowth of organisms: Prolonged or repeated use of cephalexin may result in an overgrowth of bacteria or fungi and organisms that are not killed by the medication. This can cause other infections to develop, such as yeast infections.
Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: This medication passes into breast milk. If you are a breast-feeding mother and are taking cephalexin, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
What other drugs could interact with this medication?
There may be an interaction between cephalexin and any of the following:
- cholera vaccine
- multivitamins with minerals
- sodium picosulfate
- typhoid vaccine
If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:
- stop taking one of the medications,
- change one of the medications to another,
- change how you are taking one or both of the medications, or
- leave everything as is.
An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.
Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.
All material copyright MediResource Inc. 1996 – 2020. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: www.medbroadcast.com/drug/getdrug/Cephalexin
The foods we eat can interfere with the medications we take.
Patients may not recognize that otherwise healthy foods can have severe consequences when mixed with certain drugs.
As medication experts, pharmacists should recognize their responsibility to clearly communicate the risk of possible food-drug interactions for both prescription and OTC medicines.
Here are some of the most dangerous food-drug interactions that pharmacists can help prevent:
1. Calcium-Rich Foods + Antibiotics
Dairy products such as milk, yogurt, and cheese can interfere with certain medications, including antibiotics such as tetracycline, doxycycline, and ciprofloxacin.
These antibiotics may bind to the calcium in milk, forming an insoluble substance in the stomach and upper small intestine that the body is unable to absorb.
2. Pickled, Cured, and Fermented Foods + MAIOs
This food category contains tyramine, which has been associated with a dangerous increase in blood pressure among patients taking monoamine oxidase inhibitors (MAIOs) and certain medications for Parkinson’s disease.
3. Vitamin K-Rich Foods + Warfarin
Pharmacists should counsel patients taking warfarin to maintain a consistent intake of vitamin K and avoid introducing kale, spinach, and other leafy greens to their diets.
Vitamin K is vital for the production of clotting factors that help prevent bleeding, but anticoagulants like warfarin exert their effect by inhibiting vitamin K. Therefore, an increased intake of the nutrient can antagonize the anticoagulant effect and prevent the drug from working.
4. Alcohol + Prescription Stimulants
Patients should always be wary of mixing any medication with alcohol, but some interactions are more serious than others.
For instance, ingesting alcohol while taking a prescription stimulant could cause the patient to not fully realize how intoxicated they are. This is especially true when the stimulant is being abused, but it can also happen when the patient takes the drug as prescribed.
5. Grapefruit and Grapefruit Juice + Statins
Patients should avoid eating grapefruit or drinking grapefruit juice while taking some medications, in particular statins.
Compounds in grapefruit called furanocoumarin chemicals cause an increase in medication potency by interacting with enzymes in the small intestine and liver. This interaction partially inactivates a number of medications under normal circumstances.