Yes, pepperoni can go bad if refrigerated. It will usually last about a week in the fridge, but it's best to check for signs of spoilage before eating it. Some signs that pepperoni has gone bad include: a sour smell, slimy texture, brown or black spots, and botulism poisoning (which has some pretty nasty symptoms). So if you see any of these signs, it's best to discard the pepperoni.