First off, I really feel that you should try some natural medication, at least for some period of time. In Ayurveda, triphala is a powder which is considered best for the large intestine health. Besides, prune juice is a powerful natural laxative. As for flaxseed, I have seen from experience that it works best when taken with yogurt smoothie. There are many remedies for constipation which are also backed by scientific journals. Read more here.
www.homeremedieslook.net/home-remedies-for-constipation/