Taking omeprazole long-term may cause you to develop stomach growths called fundic gland polyps. Talk with your doctor about this risk. Talk with your doctor about this risk. If you use omeprazole for longer than 3 years, you could develop a vitamin B-12 deficiency. Avoid taking more omeprazole than you are instructed to take; an overdose of omeprazole is dangerous. If you feel like your symptoms are not going away, talk to your doctor about getting a stronger prescription instead of taking more doses of omeprazole. Here it is January 2014 and I am pretty sure I have one of the possible side affects of taking omeprazole, severe itchy skin. Twice in the last month I stopped taking it for a few days and believe I even had a withdrawal side affect. This was when I was just falling to sleep it felt like I could not breath. feeling sick - try taking omeprazole with or after a meal or snack. It may also help if you don't eat rich or spicy food. It may also help if you don't eat rich or spicy food. being sick (vomiting) or diarrhoea - drink plenty of water by having small frequent sips to avoid dehydration. While you are taking Prilosec (omeprazole), a drug used to reduce stomach acid, you should avoid: becoming pregnant. Prilosec may not be safe to take during pregnancy. Do I need to avoid any food or drinks while taking omeprazole? There's nothing you need to avoid specifically because you're taking omeprazole, but if there are foods or drinks that make your. Taking omeprazole long-term may cause you to develop stomach growths called fundic gland polyps. Talk with your doctor about this risk. Talk with your doctor about this risk. If you use omeprazole for longer than 3 years, you could develop a vitamin B-12 deficiency. What should I avoid while taking omeprazole? Omeprazole can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, call your doctor before using anti-diarrhea medicine. Omeprazole has been subjected to a number of clinical tests, and there is nothing you need to avoid because you are treating acid reflux with Omeprazole. However, there are foods or drinks trigger the symptoms of indigestion, heartburn or ulcer. These are the kind of food one should avoid when taking Omeprazole. Are there supplements I should avoid, or be taking, due to this drug? Answer: Omeprazole (Prilosec), Nexium, and other proton pump inhibitor drugs can be affected by taking supplements, and can affect your ability to absorb certain vitamins and minerals.