Which antibiotic is often used to treat traveler's diarrhea associated with ETEC?

Ciprofloxacin is commonly used to treat traveler's diarrhea caused by enterotoxigenic Escherichia coli (ETEC). This antibiotic belongs to the fluoroquinolone class, which is effective against a range of bacterial infections, including those of the gastrointestinal tract. ETEC is known to produce enterotoxins that lead to secretory diarrhea; thus, an effective antibiotic is essential in reducing the duration and severity of the symptoms.

Ciprofloxacin works by inhibiting bacterial DNA gyrase and topoisomerase IV, enzymes critical for bacterial DNA replication, ultimately leading to cell death. Its broad-spectrum activity against gram-negative bacteria, including E. coli, makes it particularly suitable for treating this type of diarrhea.

Other antibiotics listed may have varying effectiveness against ETEC. Amoxicillin, being a penicillin derivative, often has limited efficacy against many E. coli strains due to resistance. Doxycycline is more commonly used for other infections, such as those caused by atypical bacteria or certain vector-borne diseases, but it is not the first choice for ETEC-related diarrhea. Clarithromycin, a macrolide antibiotic, is another option for various infections but is not specifically indicated for ETEC.

Therefore, ciprof