Medication Summary
Guidelines for therapy are usually based on the presenting symptoms and the clinical distribution of infection. Empiric antimicrobial therapy must be comprehensive and should cover all likely pathogens in the context of the clinical setting.
Successful treatment for chancroid cures the infection, resolves the clinical symptoms, and prevents chancroid transmission to others. The US Centers for Disease Control and Prevention (CDC) recommends any one of the following treatments for chancroid:
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Azithromycin 1 g orally in a single dose
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Ceftriaxone 250 mg intramuscularly in a single dose
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Ciprofloxacin 500 mg orally twice a day for 3 days
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Erythromycin base 500 mg 3 times a day for 7 days
Ciprofloxacin is contraindicated for pregnant and lactating women. Azithromycin and ceftriaxone offer the advantage of single-dose therapy. [52] Worldwide, several isolates with intermediate resistance to either ciprofloxacin or erythromycin have been reported. [42, 53]
A 2009 study of 54 subjects from Brazil suggests that single-dose therapy with thiamphenicol (89% cure rate) is more effective than single-dose therapy with azithromycin (73% cure rate). However, HIV seropositivity was associated with treatment failures. Notably, all HIV-positive subjects treated with azithromycin had treatment failure, prompting the authors to recommend avoiding azithromycin in HIV-coinfected patients. [54]
Uncircumcised men and patients who are infected with HIV do not respond to therapy as well as others. Chancroid relapses after antibiotic therapy in as many as 5% of patients, and relapses are more common in patients who are uncircumcised or are infected with HIV. If they are not infected with HIV, repeating the original therapy is usually effective.
Because chancroid treatment is often accompanied by treatment for gonococcal infections, it is important to be aware of changes to the CDC guidelines for STDs. In 2021, the CDC updated treatment guidelines for sexually transmitted diseases. Of significance to the treatment of chancroid, it details the increasing prevalence of antimicrobial-resistant Neisseria gonorrhea and recommends dual therapy for gonorrhea—the injectable cephalosporin ceftriaxone, plus oral azithromycin. For more information, see the CDC’s Antibiotic-Resistant Gonorrhea Web site.
Antibiotic, Other
Class Summary
The goal of pharmacotherapy for chancroid is to reduce morbidity and to prevent complications.
Ceftriaxone (Rocephin)
Ceftriaxone is a third-generation cephalosporin with broad-spectrum, gram-negative activity; it has lower efficacy against gram-positive organisms and higher efficacy against resistant organisms. It arrests bacterial growth by binding to 1 or more penicillin-binding proteins.
Azithromycin (Zithromax)
Azithromycin acts by binding to the 50S ribosomal subunit of susceptible microorganisms and blocks dissociation of peptidyl tRNA from ribosomes, causing RNA-dependent protein synthesis to arrest. Nucleic acid synthesis is not affected.
Azithromycin concentrates in phagocytes and fibroblasts as demonstrated by in vitro incubation techniques. In vivo studies suggest that its concentration in phagocytes may contribute to drug distribution to inflamed tissues.
Azithromycin treats mild-to-moderate microbial infections. Plasma concentrations are very low, but tissue concentrations are much higher, giving it value in treating intracellular organisms. It has a long tissue half-life.
Erythromycin (E-Mycin, Eryc, Ery-Tab)
The recommended dosing schedule for erythromycin may result in GI upset, causing one to prescribe an alternative macrolide or change to thrice-daily dosing. Erythromycin covers most potential etiologic agents, including Mycoplasma species. It is less active against Haemophilus influenzae. Although 10 days seems to be a standard course of treatment, treating until the patient has been afebrile for 3-5 days seems more rational.
It inhibits bacterial growth, possibly by blocking dissociation of peptidyl tRNA from ribosomes, causing RNA-dependent protein synthesis to arrest. It is ndicated for staphylococcal and streptococcal infections.
In children, age, weight, and severity of infection determine proper dosage. When twice-daily dosing is desired, half the total daily dose may be taken q12h. For more severe infections, double the dose. Erythromycin has the added advantage of being a good anti-inflammatory agent by inhibiting migration of polymorphonuclear leukocytes.
Ciprofloxacin (Cipro)
Ciprofloxacin is a fluoroquinolone that inhibits bacterial DNA synthesis and, consequently, growth, by inhibiting DNA gyrase and topoisomerases, which are required for replication, transcription, and translation of genetic material. Quinolones have broad activity against gram-positive and gram-negative aerobic organisms. Ciprofloxacin has no activity against anaerobes. Continue treatment for at least 2 days (7-14 d typical) after signs and symptoms have disappeared.
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Chancroid usually starts as a small papule that rapidly becomes pustular and eventually ulcerates. The ulcer enlarges, develops ragged undermined borders, and is surrounded by a rim of erythema. Unlike syphilis, lesions are tender and the border of the ulcer is not indurated. Courtesy of Hon Pak, MD.
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This patient shows the characteristic lesions of chancroid. The bubo on the right side drained spontaneously. The bubo in the left inguinal canal required needle aspiration.
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Close-up view of chancroid ulcers.
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Large fluctuant buboes should be drained with the patient under local anesthesia and a large-gauge needle inserted through surrounding healthy skin. The insertion site should be superior or lateral to the bubo to prevent chronic drainage from the site.
