Is MIRALAX safe for long term constipation?

Resolved question:
Hi there,
I have IBS-C and have had bowel issues as long as I can remember. Fiber, lots of water, and the usual solutions don't seem to work for me, and several years old patientago (we're probably pushing close to a decade, but maybe not quite), I was put on a combination of the Metamucil I was already taking and MiraLax (a dose every night). I know MiraLax's directions suggest short-term use only, but it seemed to work for me, so my doctor put me on it long-term permanently, which has improved quality of life and all-but-eliminated my bowel issues.

Unfortunately, I ran across the following, and it has me a bit concerned:
http://www.gutsense.org/gutsense/the-role-of-miralax-laxative-in-autism-dementia-alzheimer.html

I realize the site linked to is not a mainstream website, so I'm taking what they're saying with a grain of salt, but thought I'd get a second opinion just to make sure I'm not potentially ingesting a neurotoxin. (About a year ago I began experiencing bouts of muscle twitching, which I'm seeing a doctor for, but I still have no real reason for it, though fortunately if anything it's reduced since it started...it comes and goes and might be a benign condition called BFS, but reading this worried me it could be related).
Also, several months ago, I made diet changes and once again tried to get off Miralax, which worked fine for about a month (I really thought I was out of the woods), and then I ended up in the ER for almost a day because I was blocked up unable to go. So, regrettably I restarted it.
Your opinion on all this is appreciated. Since MiraLax works, is it safe for me to continue longterm, or is there a risk of damage, particularly neurological damage?
Thanks!

Submitted: 4 Days
Category: Gastroenterologist, Medical

---

• Hit left elbow, hurts to straighten or bend at elbow.

  ---

• Fever

  ---

• Time period for symptoms to develop after HIV exposure.

  ---

• Rashes in circles in legs which comes anf go.

  ---

• Helpful Tips to Overcome Premature Ejaculation Problem

  ---

• Upper GI an urinary symptoms

  ---

• Peyronie's disease and penis extenders

  ---