From the Guidelines

Azithromycin is effective against Campylobacter diarrhea.

Azithromycin has been shown to be effective in treating Campylobacter infections, particularly in cases where fluoroquinolone resistance is high 1.
The recommended dose of azithromycin for treating Campylobacter diarrhea is a single 1-gm dose or 500 mg daily for 3 days 1.
Azithromycin is generally well tolerated, with minimal side effects, and is considered a first-line agent for treating dysentery and acute watery diarrhea with greater than mild fever 1.
The use of azithromycin is supported by guidelines from various organizations, including the Infectious Diseases Society of America and the American College of Gastroenterology 1.
In cases of severe or prolonged disease, or in immunocompromised patients, azithromycin is a reasonable treatment option for Campylobacter gastroenteritis 1.
It is essential to note that while azithromycin is effective against Campylobacter, the treatment benefit is modest, and the risks of treatment may outweigh the benefits in most cases of self-limited disease 1.
The choice of antimicrobial agent may change due to evolving resistance patterns, and fluoroquinolone resistance in Campylobacter spp. is a concern 1.

From the Research

Azithromycin has been studied as a potential treatment for Campylobacter diarrhea in several clinical trials 2, 3, 4, 5, 6.
A randomized, double-blind trial comparing azithromycin with placebo for the treatment of Campylobacter concisus diarrhea in adults found no significant difference in clinical outcomes between the two groups, although the study was underpowered due to recruitment difficulties 2.
Another study found that azithromycin was effective in treating traveler's diarrhea caused by Campylobacter species, with a cure rate of 96% at 72 hours after treatment initiation 4.
Azithromycin has also been shown to be superior to ciprofloxacin in decreasing the excretion of Campylobacter species and as effective as ciprofloxacin in shortening the duration of illness 5.
The use of azithromycin as an empirical antimicrobial therapy for traveler's diarrhea has been recommended, particularly in areas where fluoroquinolone resistance is prevalent 3, 6.

Azithromycin has been compared with other antibiotics, such as levofloxacin and ciprofloxacin, in the treatment of Campylobacter diarrhea 4, 5.
The results of these studies suggest that azithromycin is a effective alternative to fluoroquinolones for the treatment of Campylobacter diarrhea, particularly in areas where fluoroquinolone resistance is prevalent.
Azithromycin has also been shown to be effective in combination with other treatments, such as loperamide, for the treatment of traveler's diarrhea 3.

The efficacy of azithromycin against Campylobacter diarrhea suggests that it may be a useful treatment option for patients with this condition 2, 3, 4, 5, 6.
However, the results of the studies should be interpreted with caution, as the quality of the evidence varies and some studies had limitations, such as small sample sizes or recruitment difficulties 2.
Further research is needed to fully establish the efficacy and safety of azithromycin for the treatment of Campylobacter diarrhea.