Took naltrexone, was heavy heroin user but went to detox, feels like a knife is in my stomach for hours what should i do?

Abdominal pain: Such pain could be due to inflammation of the stomach lining (gastritis), peptic ulcer or pancreatitis. Gall bladder and liver causes are also possible. Nevertheless you should be examined by your physician who will order any appropriate tests deemed necessary in order to make a diagnosis. In the meantime follow a bland diet and avoid alcohol, tobacco, and caffeine. Don't put off the examination.