For constipation, medication is only a very temporary solution if it works.
Wheat germ and wheat bran are very high fiber foods that often help for constipation.
Constipation can cause anal fissures, hemorrhoids and also some far more serious problems as in http://au.search.yahoo.com/search?p=%22rectal+bleeding%22&fr=ush-ans
You probably need to improve your diet as you seem to have a constipation problem.
For constipation, castor oil is very good for a one-off remedy as in http://au.search.yahoo.com/search?p=%22castor+oil+for+constipation%22&fr=ush-ans but it is unsuitable for regular use.
For constipation, suppositories, laxatives, fiber supplements and enemas are all totally unnecessary if you eat the right foods.
All fruit and vegetables in very large amounts are laxative.
You need to permanently change your diet or you are likely to get colon cancer.
Constipation can make you extremely unwell and can lead to colon cancer as it causes a build up of carcinogenic toxins in the system.
The intake of foods such as milk, cheese, white rice, white flour and red meat should be restricted, because they tend to contribute to constipation.
Any food that has had the fiber stripped out, the nutrients processed out or slows down the digestion is a constipation culprit. Here's a list of foods shown to cause constipation problems:
•Meats, especially fatty meats, red meat and processed meats,
•Dairy Products, such as cheese, ice cream and whole milk,
•Fast Foods – burgers, French fries and other fried foods, pizza, etc.,
•Refined grains, like white rice or any refined white flour products,
•Highly starchy foods – white potatoes, corn and all refined grains,
•Pastries and other high sugar products, such as cakes, cookies and pies,
•Deep-fried foods, chips and other foods that are high in bad fats.
You can see lots more in http://au.search.yahoo.com/search?p=%22natural+ways+to+relieve+constipation%22&fr=ush-ans which tells you "Natural Ways to Relieve Constipation" and the right foods to eat.