Brief Answer:
Drug Induced Constipation with IBS/ Under evaluation
Mostly from Immodium induced cloggging
-but Partial obstruction at resected small bowel surgery,causing clogging effect needs to be ruled out.
Detailed Answer:
Hi,Dear!! Thanks for the query to HCM.
Read and reviewed facts of your query for your MOM , in context to her health worries.

My Opinion-
Dear after review of the given facts,Your Mom seems to have suffered from-Immodium induced clogging effect with flare up of IBS with spastic painful sigmoid.
I would suggest to rule out adhesive partial obstruction from old resected small bowel operation,which needs Consults with General Surgeon.

-Other causes of IBS With Constipation at 92, needs to be ruled out and investigated, if need be, before planning further treatment, only if recurrence causes troublesome problem in your Mom.

Consults with a team of GI Surgeons and General Physician, may be needed in case of recurrence of Clogging with Painful Sigmoid and intestines, from IBS.
The accompanied diarrhoea with enteritis needs to be treated along with other treatments for Constipation.

Do's Suggested-
Consults with Surgeon
Nil By Mouth till bowels move out
Liquids and fruit juices if she could take it-for 2-3 days.

Bland vagan -diet with liquid base in plenty x for 3-5 days,
Butter Milk x 2 times a day.
No nonveg/ spicy,street fast food x 10 days

Medicine support from GP doctor-
PPI-like Omprezole with Domperidone(gastrokinetics)-1 x 2 per day/2 weeks
Cap Sporlac-probiotics x 2 weeks
Antibiotics with anti-protozoals -like Ciplox-with Oz x 7 days
Tab Dicyclomine with Tylenol-x for 1-3 days to control pains- to be used cautiously to avoid more clogging from it.

Sublingual Tab Vit B12+ Folic acid with Multivits and zinc, magnesium -like micro nutrients-for 1 week,which would replenish and would recoup you fast from this drug induced clogging with painful bowels.
With this you should be out of this drug induced clogging with painful IBS.
IF it persists CT abdomen and further investigations to rule out other causes for her advanced age would be needed.

Next appointment-
any time soon and / or Only after 2 weeks time to review the investigation reports with more details from you.

Hope this reply would help you to plan further care to resolve your health issues.

You are most Welcome herewith !!

Good Day!!

Wishing Good Healthy Life in time to come!!

Dr.Savaskar M.N. XXXXXXX Surgical Specialist
M.S.Genl-CVTS

---