The efficacy of bismuth-containing quadruple therapy with minocycline and metronidazole was not inferior to classical bismuth quadruple therapy for refractory H. pylori infection, though also accompanied with high occurrence of adverse events (55.4%). Optimization of minocycline-based regimen to achieve high eradication rate with fewer adverse events is imperative. This study aimed to compare the efficacy and tolerability of a 14-day bismuth-containing quadruple rescue therapy with different dosage of minocycline and metronidazole compared to classical bismuth quadruple therapy.