Cephalexin T300 26-27

Cephalexin

Keflex, Daxbia

Cephalexin Drug Class

First-Generation Cephalosporin

Cephalexin Dosage Forms

Oral Suspension: 125 mg/5 mL, 250 mg/5 mL;

Oral Tablet: 250 mg, 500 mg;

Oral Capsule:250 mg, 500 mg, 750 mg

Cephalexin Dosing By Indication

1. Osteomyelitis: Adults, 250 mg-1 g po q6h; Children, 100-150 mg/kg/d po divided q6h to q8h, max 4 g/d

2. Otitis media, respiratory tract infection, UTI: Adults, 250 mg-1 g po q6h; Children, 25-100 mg/kg/d po divided q6h, max 4 g/d

3. Streptococcal pharyngitis: Adults, 500 mg po q12h × 10 d; Children, 25-50 mg/kg/d po divided q6h × 10 d, max 4 g/d

4. Impetigo, ecthyma: 250-500 mg po qid ×7 d; Children, 25-50 mg/kg/d po divided q6h to q8h × 7 d, max 2000 mg/d

5. Cellulitis (nonpurulent), erysipelas: 500 mg po qid × 5-14 d; 25-100 mg/kg/d po divided q6h to q8h, max 500 mg/dose

Cephalexin Off Label Uses

1. Prosthetic joint infection: 500 mg po q6-8h or 1 g q8-12h

2. Endocarditis, prophylaxis (dental or invasive respiratory tract procedures): 2 g po 30-60 min prior to procedure

Cephalexin MOA

This drug is a 1st-generation cephalosporin that inhibits bacterial wall synthesis of actively dividing cells by binding to ≥1 penicillin-binding proteins (PBPs). Most gram-positive bacteria, including non–penicillinase- and penicillinase-producing staphylococci and streptococci. Activity against gram-negative bacteria is less than that observed with the 2nd- and 3rd-generation cephalosporins and is primarily restricted to Escherichia coli, Klebsiella, and Proteus mirabilis.

Cephalexin Common Adverse Effects

Nausea

Cephalexin Efficacy Monitoring Parameters

Resolution of signs and symptoms of infection.

Cephalexin Safety Monitoring Parameters

Seek medical attention if decreased urination, blistering skin rash or extreme fatigue, unusual bruising or bleeding, shortness of breath. If long duration of use, monitor SCr, LFTs, and CBC.

Cephalexin Key Counseling Points

Seek medical attention if rash develops. Complete full course of therapy. For the suspension, shake well and store in the refrigerator. Note short expiration after reconstitution. Avoid mixing suspension with food or beverages, but food can be taken afterward. Symptoms should improve within 2-3 d; if they worsen, seek follow-up with health-care practitioner.

Cephalexin Clinical Pearls

May resume normal activities after 24 h of antibiotics and if afebrile. Approximately 10% of patients allergic to penicillins are also allergic to cephalosporins; use with caution in penicillin-allergic patients. Refer to current IDSA guidelines for further details on clinical practice recommendations.