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cephalexin (Rx)Brand and Other Names:Keflex, Panixine Disperdose

 
 
 

Dosing & Uses

AdultPediatric

Dosage Forms & Strengths

capsule

  • 250mg
  • 500mg
  • 750mg

oral suspension

  • 125mg/5mL
  • 250mg/5mL

tablet

  • 250mg
  • 500mg
more...

Genitourinary Tract Infections

250 mg PO q6hr; dosage range, 1-4 g/day in divided doses

Bone Infections

250 mg PO q6hr; dosage range, 1-4 g/day in divided doses

Uncomplicated Cystitis

250 mg PO q6hr or 500 mg PO q12hr; dosage range, 1-4 g/day in divided doses

Otitis Media

250 mg PO q6hr; dosage range, 1-4 g/day in divided doses

Skin/Skin Structure Infections

250 mg PO q6hr or 500 mg PO q12hr; dosage range, 1-4 g/day in divided doses

Respiratory Tract Infections

250 mg PO q6hr; dosage range, 1-4 g/day in divided doses

Streptococcal Pharyngitis

250 mg PO q6hr or 500 mg PO q12hr; dosage range, 1-4 g/day in divided doses

Cellulitis and Mastitis

500 mg PO q6hr; dosage range, 1-4 g/day in divided doses

Renal Impairment

CrCl <10 mL/min: 250-500 mg PO q12-24hr

CrCl 10-50 mL/min: 500 mg PO q8-12hr

Hepatic Impairment

Not studied

Dosing Considerations

Susceptible organisms

  • Gram-positive cocci, gram negative bacilli, gram-positive bacilli, gram-negative cocci, anaerobes

Dosage Forms & Strengths

capsule

  • 250mg
  • 500mg

oral suspension

  • 125mg/5mL
  • 250mg/5mL

tablet

  • 125mg
  • 250mg
more...

Uncomplicated Cystitis

<15 years: 25-50 mg/kg/day PO divided q6-8hr for 10 days; not to exceed 4 g/day 

>15 years: 250 mg PO q6hr; dosage range, 1-4 g/day in divided doses

Genitourinary Tract Infections

25-50 mg/kg/day PO divided q6-8hr for 10 days; not to exceed 4 g/day 

Beta-Hemolytic Streptococcal Infections

25-50 mg/kg/day PO divided q6-8hr for 10 days; not to exceed 4 g/day 

Bone Infections

25-50 mg/kg/day PO divided q6-8hr for 10 days; not to exceed 4 g/day 

Otitis Media

75-100 mg/kg/day PO divided q6hr for 10 days; not to exceed 4 g/day  

Skin/Skin Structure Infections

25-50 mg/kg/day PO divided q6-8hr for 10 days; not to exceed 4 g/day 

Respiratory Tract Infections

25-50 mg/kg/day PO divided q6-8hr for 10 days; not to exceed 4 g/day  

Streptococcal Pharyngitis

25-50 mg/kg PO q12hr for 10 days; not to exceed 500 mg q12hr 

Cellulitis and Mastitis

Adolescents: 500 mg PO q6hr; dosage range, 1-4 g/day in divided doses

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Interactions

Interaction Checker

cephalexin and

No Results

     
     activity indicator 
    No Interactions Found
    Interactions Found

    Contraindicated

      Serious - Use Alternative

        Significant - Monitor Closely

          Minor

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            Adverse Effects

            Frequency Not Defined

            Abdominal pain

            Agitation

            Anemia

            Angioedema

            Confusion

            Diarrhea

            Dizziness

            Dyspepsia

            Elevated transaminases

            Eosinophilia hemolytic

            Epidermal necrolysis

            Erythema multiform

            Fatigue

            Gastritis

            Genital pruritus

            Hallucinations

            Headache

            Hemolytic anemia

            Hypersensitivity

            Nephritis

            Neutropenia

            Pseudomembranous colitis

            Thrombocytopenia

            Transient hepatitis

            Toxic epidermal necrolysis

            Urticaria

            Vaginal discharge

            Vomiting

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            Warnings

            Contraindications

            Documented hypersensitivity

            Cautions

            Endocarditis prophylaxis is appropriate only for high-risk patients, per American Heart Association guidelines

            Adjust dose in severe renal insufficiency (high doses may cause CNS toxicity)

            Superinfections and promotion of nonsusceptible organisms may occur with prolonged use or repeated therapy

            Prolonged treatment, hepatic or renal disease, or nutritional deficiency may be associated with increased international normalized ratio (INR)

            Prolonged use is associated with fungal or bacterial superinfection

            Use with caution in patients with history of hypersensitivity to penicillin

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            Pregnancy & Lactation

            Pregnancy category: B

            Lactation: Drug excreted in breast milk; use with caution

            Pregnancy Categories

            A:Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

            B:May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

            C:Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

            D:Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

            X:Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

            NA:Information not available.

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            Pharmacology

            Mechanism of Action

            Binds to one or more of the penicillin binding proteins, which in turn inhibits synthesis of bacterial cell wall

            Absorption

            Bioavailability: 90%; absorption delayed in young children

            Peak serum time: 1 hr

            Peak plasma concentration: 10-18 mcg/mL (500-mg dose)

            Distribution

            Distributed widely into most tissues and fluids; penetrates CSF poorly

            Protein bound: 6-15%

            Metabolism

            Minimally metabolized in liver

            Elimination

            Half-life: 0.5-1.2 hr

            Excretion: Urine (80-100% as unchanged drug)

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            Formulary

            FormularyPatient Discounts

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            The above information is provided for general informational and educational purposes only. Individual plans may vary and formulary information changes. Contact the applicable plan provider for the most current information.

            Tier Description
            1 This drug is available at the lowest co-pay. Most commonly, these are generic drugs.
            2 This drug is available at a middle level co-pay. Most commonly, these are "preferred" (on formulary) brand drugs.
            3 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs.
            4 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            5 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            6 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            NC NOT COVERED – Drugs that are not covered by the plan.
            Code Definition
            PA Prior Authorization
            Drugs that require prior authorization. This restriction requires that specific clinical criteria be met prior to the approval of the prescription.
            QL Quantity Limits
            Drugs that have quantity limits associated with each prescription. This restriction typically limits the quantity of the drug that will be covered.
            ST Step Therapy
            Drugs that have step therapy associated with each prescription. This restriction typically requires that certain criteria be met prior to approval for the prescription.
            OR Other Restrictions
            Drugs that have restrictions other than prior authorization, quantity limits, and step therapy associated with each prescription.
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