Brief Answer:
I would suggest you to go with Miralax

Detailed Answer:
Hi,
Thanks for your query,
I'm Dr. Remy and I would be answering your concerns today

Both magnesium citrate and Miralax are osmotic laxatives that act by keeping more water in your bowels thus helping in softening the stools and thereby its easy passage.
If you are having chronic constipation I would suggest you to go with Miralax which is effective and can be used for longer periods.

You may also consider using Dulcolax (bisacodyl) which gives instant relief from constipation, but it's not to be used for long periods.

In addition, I would recommend some life style changes:
- drinking plenty of water preferrable warm water
- taking fruits rich in fiber content like apple, bananas, oranges, strawberries
- daily exercise for a minimum of 30 mins

Hope this helps
Please feel free to discuss further, I would be pleased to assist you further
Thanks
Regards

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