I'm doing the quad therapy for h. pylori. antibio and pepto and ppi 4 times a day. should i take pepto bismol (bismuth subsalicylate) together or at diff time than antibios?

Before meals: usually you take the PPI and or pepto about 30 minutes prior to a meal for better acid suppression and the antibiotics with a meal/food. However, compliance and complete completion are the most important parts of treating H. Pylori to avoid resistance and improve efficiency. So if you have a hard time remembering when to take the pills then just take them together the directed times of day total

I would separate: the time between antibiotics and pepto by 4-6 hours, just to be safe.