Azithromycin triple therapy for Helicobacter pylori infection: azithromycin, tetracycline, and bismuth.
BACKGROUND
Azithromycin is new acid-stable macrolide that achieves 10- to 40-fold higher tissue levels than erythromycin after oral dosing. Important to note, the tissue half-life of azithromycin is measured in days instead of hours.


METHODS
We evaluated two new triple therapies for Helicobacter pylori infection in which azithromycin was substituted for metronidazole either as 250 mg b.i.d. or t.i.d. along with tetracycline 500 mg q.i.d. and bismuth subsalicylate 2 tablets q.i.d. for 14 days. H. pylori status was determined by histology before and 6 wk or more after therapy.


RESULTS
Thirty men with documented H. pylori peptic ulcers completed therapy. Twenty-one also received ranitidine (300 mg in the evening) along with the antimicrobial therapy. H. pylori infection was successfully treated in 15 (50%) (95% CI = 31-69%). The cure rate was significantly higher with the 250-mg-t.i.d.-azithromycin dosage regime (83%) (95% CI = 52-98%) compared to the 250-mg-b.i.d.-dosage regime (28%) (95% CI = 10-53%) (p < 0.01). Troublesome side effects were experienced by the majority of those receiving azithromycin t.i.d.


CONCLUSIONS
We conclude that although 750 mg or more of azithromycin might eventually be able to replace metronidazole or clarithromycin in standard triple therapy, additional studies are required to identify a regime that is both effective and tolerable.
al-Assi
M T
MT
Department of Medicine, Veterans Affairs Medical Center, Houston, Texas.
Genta
R M
RM
Karttunen
T J
TJ
Cole
R A
RA
Graham
D Y
DY
D017963:Azithromycin / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D001729:Bismuth / Q000008:administration & dosage* / Q000627:therapeutic use; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D016481:Helicobacter Infections / Q000188:drug therapy*; D016480:Helicobacter pylori; D006801:Humans; D008297:Male; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage* / Q000627:therapeutic use; D010437:Peptic Ulcer / Q000188:drug therapy / Q000382:microbiology; D011899:Ranitidine / Q000627:therapeutic use; D012459:Salicylates / Q000008:administration & dosage* / Q000627:therapeutic use; D013752:Tetracycline / Q000008:administration & dosage* / Q000627:therapeutic use
D009942:Organometallic Compounds; D012459:Salicylates; C015715:bismuth subsalicylate; D017963:Azithromycin; D011899:Ranitidine; D013752:Tetracycline; D001729:Bismuth