Brief Answer:
may need a different type of laxative

Detailed Answer:
HI, thanks for using healthcare magic

Fleet is normally effective in treating acute constipation, it is a lubricant laxative that normally works within 8 hours.
Ducolax works as a stimulant laxative

Since neither of these have worked for you, you may need to try another type of laxative such as an osmotic laxative like miralax which is also over the counter (highly effective but , works with 1 to 4 days,can be used for a few days but no more than week) or senna which is also a stimulant like ducolax but works a little differently

Senna causes a response in 8 to 12 hours
Make sure to use enough fluids to help with the stool loss

In terms of preventing future episodes: (A) need to drink at least 8 glasses of fluids daily
This cannot include caffeine drinks or alcohol because both of these have a diuretic effect and cause the body to lose fluids

(B)use at least 5 servings or more of fiber daily- this includes fruits, vegetables, whole grain foods

Some persons need fiber supplements because it can be hard to get enough dietary fiber eg cetrucil, metamucil, benefiber

(c)as much physical activity as possible

(D) bowel training- try for a bowel movement at approximately the same time daily or within thirty mins of a meal or very soon after a walk

I hope this helps, feel free to ask any other questions

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