No. Pepto Bismol is for diarrhea and upset stomach. It will make you more constipated as it helps harden the stool. Eat some figs or prunes. Drink lots of water.If all else fails a warm water enema will provide relief in minutes.est Answer: Pepto won't do anything for constipation, it's used when you have diarrhea. You need to use a stool softener (like docusate) or laxative (like senna or milk of magnesia). Source(s): Pharmacist. daddyrx · 4 years ago.