What is the recommended dose of cephalexin (cephalexin) for the treatment of otitis externa?

From the Guidelines

For otitis externa, cephalexin is not typically the first-line antibiotic treatment, but if prescribed, the recommended dose is 250-500 mg taken orally four times daily for 7-10 days for adults, and 25-50 mg/kg/day divided into four equal doses for children 1. The recommended treatment for otitis externa usually involves topical antibiotic preparations rather than oral antibiotics like cephalexin.

• Topical treatments such as ofloxacin otic solution, ciprofloxacin/dexamethasone, or neomycin/polymyxin B/hydrocortisone are generally preferred because they deliver medication directly to the infected area with minimal systemic effects.
• If oral antibiotics are deemed necessary for severe cases or when infection has spread beyond the ear canal, cephalexin may be prescribed. However, it's essential to note that treatment should be guided by culture results when possible, as many cases of otitis externa are caused by Pseudomonas aeruginosa, which is not effectively treated by cephalexin 1. Additionally, keeping the ear dry is crucial for recovery, so patients should avoid swimming and use earplugs when showering. The dosage of cephalexin for skin and soft-tissue infections, including impetigo, is 250 mg four times a day for adults and 25-50 mg/kg/day in three to four divided doses for children, as stated in the 2014 update by the Infectious Diseases Society of America 1.

From the FDA Drug Label

The usual adult dose is 250 mg every 6 hours For the following infections, a dosage of 500 mg may be administered every 12 hours: streptococcal pharyngitis, skin and skin structure infections, and uncomplicated cystitis in patients over 15 years of age. In severe infections, the dosage may be doubled.

The recommended dose of cephalexin for the treatment of otitis externa is not explicitly stated in the drug label. However, since otitis externa is a type of skin and skin structure infection, the dose for this type of infection can be considered.

• The usual adult dose for skin and skin structure infections is 250 mg every 6 hours or 500 mg every 12 hours.
• For severe infections, the dosage may be doubled. 2

From the Research

Cephalexin Dose for Otitis Externa

• The recommended dose of cephalexin for the treatment of otitis externa is not explicitly stated in the provided studies 3, 4, 5, 6, 7.
• However, it is worth noting that cephalexin is an oral antibiotic, and the studies provided focus on topical treatments for otitis externa, such as acetic acid, aminoglycosides, polymyxin B, and quinolones 3, 4, 6, 7.
• One study compares the efficacy of cefixime and amoxicillin/clavulanate in acute otitis media, but does not provide information on cephalexin dosing for otitis externa 5.
• Another study compares the efficacy of ciprofloxacin and a combination of oxytetracycline, polymyxin B, and hydrocortisone in treating otitis externa, but does not mention cephalexin 6.
• A combined analysis of two clinical trials compares the treatment failure rates of ciprofloxacin/dexamethasone and neomycin/polymyxin B/hydrocortisone in acute otitis externa, but does not provide information on cephalexin dosing 7.

Alternative Treatments

• Topical antimicrobials or antibiotics, such as acetic acid, aminoglycosides, polymyxin B, and quinolones, are the treatment of choice in uncomplicated cases of otitis externa 4.
• Oral antibiotics, such as cephalexin, may be reserved for cases in which the infection has spread beyond the ear canal or in patients at risk of a rapidly progressing infection 4.