Some suggestions -
Increase the amount of fibre in your diet (try cereals such as shredded wheat/weetabix/branflakes, plus drink more water. If that does not work and you do not wish to take laxatives, then you could go to a Chinese herbalist shop and get herbal tea's which would help.
If you're really backed up try Prunes/ Prune Juice - not too much....
Or if taste is not a problem you could try Ortisan from health food shops or a bottle of 'living bitters'. (you only need a teaspoon) and you should get a 'result' within 1 hour :D
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