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Related to Cefalexin: amoxicillin


a semisynthetic, first-generation cephalosporin antibiotic, effective against a wide range of gram-positive and a limited number of gram-negative bacteria; administered orally as the base or the hydrochloride salt in the treatment of tonsillitis, otitis media, and infections of the genitourinary tract, of bones and joints, and of skin and soft tissues.


Apo-Cephalex, Biocef, Dom-Cephalexin, Keflex, Novo-Lexin, Nu-Cephalex, Panixine DisperDose, PMS-Cephalexin

Pharmacologic class: First-generation cephalosporin

Therapeutic class: Anti-infective

Pregnancy risk category B


Interferes with bacterial cell-wall synthesis, causing cell to rupture and die. Active against many gram-positive bacteria; shows limited activity against gram-negative bacteria.


Capsules: 250 mg, 500 mg, 750 mg

Oral suspension: 125 mg/5 ml, 250 mg/5 ml

Tablets: 250 mg, 500 mg

Indications and dosages

Respiratory tract infections caused by streptococci; skin and skin-structure infections caused by methicillin-sensitive staphylococci and streptococci; bone infections caused by methicillin-sensitive staphylococci or Proteus mirabilis; genitourinary infections caused by Escherichia coli, P. mirabilis, and Klebsiella species; Haemophilus influenzae, methicillin-sensitive staphylococcal, streptococcal, and Moraxella catarrhalis infections
Adults: 1 to 4 g P.O. daily in divided doses (usually 250 mg P.O. q 6 hours). For uncomplicated cystitis, skin and soft-tissue infections, and streptococcal pharyngitis, 500 mg P.O. q 12 hours.
Children: 25 to 50 mg/kg/day P.O. in divided doses

Otitis media caused by S. pneumoniae
Children: 75 to 100 mg/kg/day P.O. in four divided doses

Dosage adjustment

• Renal impairment


• Hypersensitivity to cephalosporins or penicillin


Use cautiously in:

• renal impairment, phenylketonuria

• history of GI disease

• debilitated or emaciated patients

• elderly patients

• pregnant or breastfeeding patients.


• Give with or without food.

• Refrigerate oral suspension.

Adverse reactions

CNS: fever, headache, lethargy, paresthesia, syncope, seizures

CV: edema, hypotension, vasodilation, palpitations, chest pain

EENT: hearing loss

GI: nausea, vomiting, diarrhea, abdominal cramps, oral candidiasis, pseudomembranous colitis

GU: vaginal candidiasis, nephrotoxicity

Hematologic: lymphocytosis, eosinophilia, bleeding tendency, hemolytic anemia, neutropenia, thrombocytopenia, agranulocytosis, bone marrow depression

Musculoskeletal: joint pain

Respiratory: dyspnea

Skin: rash, maculopapular and erythematous urticaria

Other: superinfection, chills, pain, allergic reaction, hypersensitivity reactions including anaphylaxis, serum sickness


Drug-drug. Aminoglycosides, loop diuretics: increased risk of nephrotoxicity

Chloramphenicol: antagonistic effect

Probenecid: increased cephalexin blood level

Drug-diagnostic tests. Alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, bilirubin, blood urea nitrogen, creatinine, eosinophils, lactate dehydrogenase, lymphocytes: increased values
Coombs' test: false-positive result (especially in neonates whose mothers received drug before delivery)

Granulocytes, neutrophils, white blood cells: decreased counts

Patient monitoring

• Assess for signs and symptoms of serious adverse reactions, including hypersensitivity, severe diarrhea, and bleeding.

• During long-term therapy, monitor CBC and liver and kidney function test results.

Patient teaching

Instruct patient to stop taking drug and contact prescriber immediately if he develops rash or difficulty breathing.

• Tell patient to take drug with full glass of water.

• Advise patient to report severe diarrhea.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.


/ceph·a·lex·in/ (-lek´sin) a semisynthetic first-generation cephalosporin, effective against a wide range of gram-positive and a limited range of gram-negative bacteria; used as the base or the hydrochloride salt.


A semisynthetic cephalosporin antibiotic, C16H17N3O4S, used especially in the treatment of respiratory and urinary tract infections.


an oral first-generation cephalosporin antibiotic.
indications It is prescribed for oral treatment of selected infections caused by susceptible bacterial strains, especially lower respiratory tract, urinary tract, skin and soft tissue, and bone and joint infections. It is also used as a prophylaxis against bacterial endocarditis in high-risk patients undergoing surgical or dental procedures.
contraindications Known hypersensitivity to this drug or to any cephalosporin medication prohibits its use, as does severely impaired renal function. It is used with caution in patients who are allergic to penicillin or other drugs.
adverse effects Nausea, diarrhea, and hypersensitivity reactions may occur.


Keflex® Infectious disease A 3rd generation broad-spectrum cephalosporin


Cefalexin, a CEPHALOSPORIN antibiotic effective by mouth. Brand names are Ceporex and Keflex.


a first generation cephalosporin antibiotic which is effective following oral administration. It is widely used in bacterial infections of the skin in dogs and cats.
References in periodicals archive ?
When the antibiotic sensitivity tests were conducted, the genus Aeromonas showed more pronounced sensitivity to the antibiotics cefalotin, chloramphenicol, cefotaxime, nalidixic acid, erythromycin, cefalexin, tetracycline, and cefaclor.
In hospital 1, the drug that was widely used for respiratory diseases (LRTI, URTI) and fever was amoxicillin followed by cefalexin and cefixime.
Antimicrobial % sensibility/ Risk of bacterial resistance % resistance RAP CI 95% Value P Penicillin 0/100 Reference Reference NA Amoxicillin 17/83 0,049 0,01-0,38 <0,004 Ampicillin 0/100 1,0 0,06-16,21 >0,1 Cefalexin 25/75 0,03 0,004-0,23 <0,001 Cloranfenicol 85/15 0,002 0,001-0,01 <0,0001 Doxiciclin 50/50 0,01 0,001-0,07 <0,0001 Enrofloxacin 75/25 0,003 0,001-0,02 <0,0001 Florfenicol 67/33 0,005 0,001-0,04 <0,0001 Gentamicin 75/25 0,003 0,001-0,02 <0,0001 Neomicin 0/100 1,0 0,06-16,21 >0,1 Norfloxacin 50/50 0,01 0,001-0,07 <0,0001 Tetraciclin 50/50 0,01 0,001-0,07 <0,0001 RAP: Ratio of adjusted proportions; CI 95%: Confidence interval 95% probability; NA: Not Applicable.
The duties, agreed without discussion at the EU's General Affairs Council, apply to three semi-synthetic penicillins: amoxicillin trihydrate, ampicillin trihydrate and cefalexin.
1) Cap Amplicllin and Cloxacillin (250+250), Cap Amoxycilline 500 mg, Cap amoxycilline 250 mg, Tab Cefixime 200 mg, Tab Azithromycine 500 MG, Cap Cefalexin 500 mg
Empirical antibiotic which can be selected for oral administration include amoxycillin clavulanate, TMP-SMX, cefixime, sefpodoxim, cefprozil, cefuroxime axetil and cefalexin.
If an additional infectious process is suspected, due to the slow evolution of the dermonecrotic process, this makes it inclined to Gram positive microorganisms (streptococci and staphylococci) attraction, considering the use of cloxacylin, flucloxacylin, cefalexin, oral penicillin or clindamycin necessary.