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Related to cephalexin: Geodon


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.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


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.

McGraw-Hill Nurse's Drug Handbook, 7th Ed. Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved


A semisynthetic cephalosporin antibiotic, C16H17N3O4S, used especially in the treatment of respiratory and urinary tract infections.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


Keflex® Infectious disease A 3rd generation broad-spectrum cephalosporin
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


Cefalexin, a CEPHALOSPORIN antibiotic effective by mouth. Brand names are Ceporex and Keflex.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
References in periodicals archive ?
(%) 90 days before LMP Medication to LMP Total pregnancies with UTIs 10,864 Any antibiotic 8,264 (76.1) Fluoroquinolones 2,927 (26.9) Ciprofloxacin 2,768 (25.5) Levofloxacin 165 (1.5) Nitrofurantoin 2,604 (24.0) Trimethoprim-Sulfamethoxazole 2,031 (18.7) Cephalosporins 560 (5.2) Cephalexin 445 (4.1) Cefuroxime 57 (0.5) Cefdinir 32 (0.3) Penicillins 276 (2.5) Amoxicillin ** 248 (2.3) Ampicillin 17 (0.2) Other 313 (2.9) Metronidazole ([dagger][dagger]) 188 (1.7) Azithromycin ([dagger][dagger]) 55 (0.5) Other 159 (1.5) Period, no.
Absorption kinetics and bioavailability of cephalexin in the dog after oral and intramuscular administration.
Against the cephalosporins resistance was 86% to cefotaxime and 91% to cephalexin. Resistance to the quinolones was 50% to ciprofloxacin and 36% each to nalidixic acid and norfloxacin.
(Table 5) was found to be maximum sensitive for Ciprofloxacin (100%) followed by Norfloxacin (100%), Ceftriaxone (100%), Cefotaxime (100%) and Tobramycin (50%) while resistant to Chloramphenicol, Gentamicin, Amikacin, Kanamycin, Neomycin, Enrofloxacin, Cephalexin, Clindamycin and Streptomycin.
Cephalexin (7-[(aminophenyl acetyl) amino]-3-methyl-8-oxo-5-thia-l-azabicyclo [4.2.0] oct-2-ene-2-carboxylic acid) is a semisynthetic b-lactam antibiotic, which belongs to the group of cephalosporin antibiotics.
Keywords: Ozonation, Activated Carbon, Optimization, Cephalexin, COD, Water Treatment, Response Surface Methodology
Sensitivity to antibiotic was studied with ampicillin, cephalexin, chloramphenicol, ciprofloxacin, erythromycin, gentamycin, streptomycin and nalidixic acid with concentration of 10, 30, 30, 5, 15, 10, 10 and 30 mg/disc, respectively.
penicillin 91.77, cloxacillin 41.27, erythromycin 77.13, azithromycin 69.07, Amikacin 31.32, gentamicin 44.57, ciprofloxacin 74.63, gatifloxacin 82.34, tetracycline 9.43, cephalexin 46.32, cefuroxime 54.95, cefoperazone 90.89, Linezolid 0.37, vancomycin13.63 and piperacillin+tazo 45.09 (Table 10).
There was no difference in outcome between the two groups, with the conclusion that addition of trimethoprim-sulfamethoxazole to cephalexin did not lead to a better outcome than cephalexin alone in patients with nonpurulent cellulitis.
This table shows, when sensitivity tests were done for different antibiotics, amongst Gram Negative bacteria isolated highest sensitive drug was found for Nitrofurantoin (80%) followed by Cephalexin (60%), Amoxyclav (60%), Norfloxacin (50%) and Gentamycin (40%).
For instance, cephalexin recommends refrigerating the suspension, while cefdinir recommends storing the suspension at room temperature.
(3) Investigators noted no significant differences between topical mupirocin and bacitracin and oral antibiotics other than erythromycin, although in one small study (10 patients), oral cephalexin resulted in a higher rate of cure or improvement than topical bacitracin (absolute risk reduction [ARR]=56.7%; NNT=2).