Also found in: Dictionary, Thesaurus, Wikipedia.
Related to Keflex: cephalexin


trademark for preparations of cephalexin, an oral cephalosporinantibiotic.
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 trademark for the drug cephalexin.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


A brand name for CEPHALEXIN (cefalexin).
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
References in periodicals archive ?
Keflex is a cephalosporin class of antibiotics, with over 22m prescriptions dispensed annually.
The recommended treatment was cephalexin (Keflex) plus trimethoprim-sulfamethoxazole (TMP/SMX).
The way the volume targets were set, hospitals would reach the minimum in Keflin and Keflex and would not typically be able to hit the volume in Kafocin and Loridine.
A good example is cephalosporin (generic name) and a few of the brand names you might see: Ancef, Ceflin, Keflex, Rocephin, and Zinacef.
Keflex was started as initial empiric therapy but was promptly discontinued when pseudomonas aeruginosa was identified on culture.
5, 2002) ("If your child has strep throat, your pediatrician will likely prescribe an oral antibiotic such as penicillin, a brand of cephalosporin (Ancef, Keflex, Cefaclor) or clindamycin (Cleocin).");, Syphilis, at (Jan.
Biaxin Clarithromycin Abbott Laboratories Biocef, Cephalexin, Cephalexin International Ethi- Keflex cal Labs (Biocel), Dista Products and Eli Lilly and Co.
Penicillin successors such as tetracycline have given way to more recent treatments such as cephalexin, commonly known by its patent name Keflex. Today the newer cephalosporin and quinolones, which are effective against a wider spectrum of bacteria than older antibiotics, are reducing treatment failures and the need for additional care or hospitalization.
She was treated with Keflex for a presumed bacterial cellulitis.
Visited a DO who was doing cross-coverage for my DO who was out of town and was diagnosed with sinus headache and given Keflex.
Clindamycin (Cleocin) is effective against MRSA; cephalexin (Keflex) is not.
According to MiddleBrook, which also markets the Keflex brand of immediate-release cephalexin, Moxatag's formulation consists of one immediate-release and two delayed-release components of amoxicillin.