First-line H. pylori eradication therapy for patients hypersensitive to penicillins

For patients with hypersensitivity to penicillins, replace amoxicillin in the standard first-line H. pylori eradication regimen with metronidazole. Use:

a proton pump inhibitor orally, twice daily for 7 to 14 days:

1esomeprazole 20 mg orally, twice daily for 7 to 14 days esomeprazole esomeprazole esomeprazole

OR

1lansoprazole 30 mg orally, twice daily for 7 to 14 days lansoprazole lansoprazole lansoprazole

OR

1omeprazole 20 mg orally, twice daily for 7 to 14 days omeprazole omeprazole omeprazole

OR

1pantoprazole 40 mg orally, twice daily for 7 to 14 days pantoprazole pantoprazole pantoprazole

OR

1rabeprazole 20 mg orally, twice daily for 7 to 14 days rabeprazole rabeprazole rabeprazole

PLUS

metronidazole 400 mg orally, twice daily for 7 to 14 days metronidazole metronidazole metronidazole

PLUS

clarithromycin 500 mg orally, twice daily for 7 to 14 days. clarithromycin clarithromycin clarithromycin

For advice on duration of therapy, see Duration of therapy for first-line H. pylori eradication therapy in adults.

Eradication rates of approximately 80% have been reported with this regimen, though pretreatment H. pylori resistance to metronidazole reduces the efficacy.

An alternative is to use bismuth-based quadruple therapy, as this does not contain penicillin and has good efficacy.

Another strategy is to perform an allergy assessment in patients who report an unconfirmed, remote or unconvincing history of penicillin allergy (see Penicillin hypersensitivity). Many of these patients are shown not to have true penicillin hypersensitivity, and standard first-line therapy containing amoxicillin may be used.