Keflex (Cephalexin) - Side Effects and Adverse Reactions

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ADVERSE REACTIONS

Gastrointestinal — Onset of pseudomembranous colitis may occur during or after antibacterial treatment. (See WARNINGS.) Nausea and vomiting have been reported rarely. The most frequent side effect has been diarrhea. It was very rarely severe enough to warrant cessation of therapy. Dyspepsia, gastritis, and abdominal pain have also occurred. As with some penicillins and some other cephalosporins, transient hepatitis and cholestatic jaundice have been reported rarely.

Hypersensitivity — Allergic reactions in the form of rash, urticaria, angioedema, and, rarely, erythema multiforme, Stevens-Johnson syndrome, or toxic epidermal necrolysis have been observed. These reactions usually subsided upon discontinuation of the drug. In some of these reactions, supportive therapy may be necessary. Anaphylaxis has also been reported.

Other reactions have included genital and anal pruritus, genital moniliasis, vaginitis and vaginal discharge, dizziness, fatigue, headache, agitation, confusion, hallucinations, arthralgia, arthritis, and joint disorder. Reversible interstitial nephritis has been reported rarely. Eosinophilia, neutropenia, thrombocytopenia, hemolytic anemia, and slight elevations in AST and ALT have been reported.

In addition to the adverse reactions listed above that have been observed in patients treated with Keflex, the following adverse reactions and altered laboratory tests have been reported for cephalosporin class antibiotics:

Adverse Reactions — Fever, colitis, aplastic anemia, hemorrhage, renal dysfunction, and toxic nephropathy.
Several cephalosporins have been implicated in triggering seizures, particularly in patients with renal impairment when the dosage was not reduced (see INDICATIONS AND USAGE and PRECAUTIONS, General). If seizures associated with drug therapy should occur, the drug should be discontinued. Anticonvulsant therapy can be given if clinically indicated.
Altered Laboratory Tests — Prolonged prothrombin time, increased BUN, increased creatinine, elevated alkaline phosphatase, elevated bilirubin, elevated LDH, pancytopenia, leukopenia, and agranulocytosis.

REPORTS OF SIDE EFFECTS / ADVERSE REACTIONS RELATED TO KEFLEX

Below is a sample of reports where side effects / adverse reactions may be related to Keflex. The information is not vetted and should not be cosidered as verified clinical evidence.

Possible Keflex side effects / adverse reactions in 58 year old female

Reported by a physician from United States on 2007-01-29

Patient: 58 year old female

Reactions: Oral Intake Reduced, Drug Dose Omission, Application Site Reaction, Staphylococcal Infection, Drug Hypersensitivity, Toxic Epidermal Necrolysis, Erythema Multiforme, Herpes Zoster

Suspect drug(s):
Aldara
    Dosage: 0.5 scahet, 5 in 1 weeks (s)), topical
    Administration route: Topical
    Indication: Actinic Keratosis
    Start date: 2006-01-01
    End date: 2006-01-01

Aldara
    Dosage: 0.5 scahet, 5 in 1 weeks (s)), topical
    Administration route: Topical
    Indication: Basal Cell Carcinoma
    Start date: 2006-01-01
    End date: 2006-01-01

Aldara
    Dosage: 0.5 scahet, 5 in 1 weeks (s)), topical
    Administration route: Topical
    Indication: Actinic Keratosis
    Start date: 2006-12-25
    End date: 2007-01-13

Aldara
    Dosage: 0.5 scahet, 5 in 1 weeks (s)), topical
    Administration route: Topical
    Indication: Basal Cell Carcinoma
    Start date: 2006-12-25
    End date: 2007-01-13

Altace

Hydrochlorothiazide

Zetia

Folic Acid

Aspirin

Fish OIL

Keflex

Possible Keflex side effects / adverse reactions in 58 year old female

Reported by a physician from United States on 2007-01-30

Patient: 58 year old female

Reactions: Staphylococcal Skin Infection, Toxic Epidermal Necrolysis, Oral Mucosal Exfoliation, Eosinophilia, Fatigue, Malaise, Erythema Multiforme, Application Site Scab

Suspect drug(s):
Aldara
    Dosage: (0.5 sachet, 5 in 1 week (s)), topical
    Administration route: Topical
    Indication: Actinic Keratosis
    Start date: 2006-01-01
    End date: 2006-01-01

Aldara
    Dosage: (0.5 sachet, 5 in 1 week (s)), topical
    Administration route: Topical
    Indication: Basal Cell Carcinoma
    Start date: 2006-01-01
    End date: 2006-01-01

Aldara
    Dosage: (0.5 sachet, 5 in 1 week (s)), topical
    Administration route: Topical
    Indication: Actinic Keratosis
    Start date: 2006-12-25
    End date: 2007-01-13