Medications for TRAVELER's diarrhea

Azithromycin (Zithromax) 1 g as a single dose is effective for traveller's diarrhea, including some cases resistant to quinolones.....
Abdelwahab Ward, BS Pharm, PharmD

As a pharmacy doctor, people often ask you, what to use for traveler's diarrhea. Travelers' diarrhea refers to diarrhea that develops in individuals from resource-rich settings during or within 10 days of returning from travel to resource-limited countries or regions. And these some medications used for managing traveler's diarrhea...

     Bismuth subsalicylate (Pepto-Bismol, NOT available in Egypt) works for mild cases and also for prevention. Suggest 2 tabs every 30 minutes for up to 8 doses for TREATMENT, or 2 tabs QID for up to 3 weeks for PREVENTION. Warn people about possible black tongue and stools. Loperamide (Imodium) is better at controlling diarrhea than bismuth and has a faster onset. But caution not to use it if patients have signs of a more serious infection such as fever or bloody stools.

Quinolones (ciprofloxacin, etc) are still recommended for treating traveler's diarrhea in most areas. However, the development of resistance and adverse effects (e.g., tendon rupture, peripheral neuropathy, QT prolongation, hypoglycemia, CNS effects, etc) has limited their use. One-day regimens are often effective but recommend 3 days for severe diarrhea. Tell patients to finish the antibiotic course unless symptoms are gone within 24 hours, (see Table 1).

Table (1). Oral antibiotics for treatment of travelers' diarrhea in adults
Drug Dosing (Adults) Comments
Azithromycin (Zithromax) Treatment: 1000 mg po x1 dose Fluoroquinolones are the drug of choice for treatment of traveler's diarrhea, but resistant species of Campylobacter and other enteropathogens have occurred in southeast Asia and the Indian subcontinent.

Azithromycin is active against fluoroquinolone-resistant species and is safe for children and pregnant women.
Bismuth subsalicylate
(Pepto-Bismol, etc)		 Symptomatic treatment: 524 mg as either tabs or liquid po every 30 minutes for up to 8 doses in 24 hours Insoluble bismuth salts may cause black tongue and stools.

Bismuth subsalicylate should be avoided in patients with aspirin allergy; renal insufficiency; gout; and those taking anticoagulants, probenecid, or methotrexate. It shouldn't be used in children younger than two years of age.

Use bismuth for symptomatic treatment of mild disease and loperamide for symptomatic treatment of moderate-to-severe disease.
Prophylaxis: 524 mg as tablets or 1048 mg as liquid po QID
Ciprofloxacin
(Ciprobay)		 Treatment: 500 mg po BID None.
Prophylaxis: 500 mg po daily
Levofloxacin
(Tavanic)		 Treatment: 500 mg po daily Levofloxacin is likely to be effective for prophylaxis but has not been studied.
Loperamide
(Imodium)		 Symptomatic treatment:
4 mg po then 2 mg po after each loose stool not to exceed 16 mg daily		 Loperamide is not recommended for patients with bloody stools or temperature over 38.5 degrees Celsius.

Results from studies combining loperamide with antibiotic treatment for decreasing duration of diarrhea are mixed.
Norfloxacin Treatment: 400 mg po BID None.
Prophylaxis: 400 mg po daily
Ofloxacin Treatment: 200 mg po BID Ofloxacin is likely to be effective for prophylaxis but has not been studied.
Rifaximin
(Gastrobiotic)		 Treatment: 200 mg po TID Rifaximin is an alternative to fluoroquinolones for patients without bloody stools or fever. Its absorption is limited and it is as effective as ciprofloxacin for enterotoxigenic E. coli (ETEC). It is not approved for use against Salmonella, Shigella, or Campylobacter species.

Rifaximin is not approved for patients younger than 12 years old. It is not approved in Canada.
Prophylaxis: 200 mg po daily or BID
  • Prophylaxis should be recommended for no more than three weeks.
  • Oral rehydration salts (ORS) solution is appropriate for preventing or treating dehydration, especially in young children and infants. 
  • ORS packets are commercially available in almost all developing countries.
  • Travelers should be provided with enough antibiotic for three days of treatment. Advise them to stop sooner if symptoms are resolved.
  • IDSA = Infectious Diseases Society of America.

Azithromycin (Zithromax) 1 g as a single dose is effective for traveler's diarrhea, including some cases resistant to quinolones. Suggest azithromycin for travellers to Southeast Asia where quinolone-resistant Campylobacter is more common, or for patients who can't take quinolones, such as pregnant women.

TMP/SMX or doxycycline is NOT recommended for traveler's diarrhea due to high levels of resistance to these agents. Also, probiotics (Lactobacillus, etc) are NOT effective for treatment, but some might have a modest benefit for prevention. For those who want to try them, suggest products containing Lactobacillus (Lacteol Forte, etc).

Also remind patients they can reduce their risk by using bottled water, consuming hot well-cooked foods, peeling fruit, etc. Consider opportunities available to you in travel medicine. Some pharmacists are helping travelers prepare for trips by advising on vaccines, motion sickness medications, antidiarrheals, sunscreens, insect repellents, etc. They are also providing information on malaria and other risks.

REFERENCES

Abdelwahab Ward, BS Pharm, PharmD