Hello, XXXXXXX,
It is all not in your head !
You are a young gentleman who started having problems
since the age of 12 and your description fits the class of
"Irritable Bowel Syndrome ". Typically, most people experience
either diarrhea predominant symptoms or constipation.
This is also associated with abdominal pain,bloating and gas.
There are some who have alternating conditions.
In your case, what you have is called "Increased Gastro-Colic
Reflex". In other words, after you eat, the contractions in
the stomach stimulates the contraction in the colon and
you get the urge to evacuate and run to the bathroom.
You may not have much of stool, although sometimes you
can see semi digested or undigested food.
In general, sugary foods or starches go through the stomach
much faster than fatty foods.
Stress and anxiety can make the symptoms worse but that
is not the cause of it. This is related to serotonin, a hormone
that has brain-gut control. The sensitivity to serotonin is
incresed in people with IBS. And also, any kind of distension
will add to the pain.
To slow down the contractions, you need to add bulk or fiber
to your diet. There are a number of fiber supplements such
as Metamucil or Effersyllium etc. and your pharmacist can
recommend one. They come in powder form, capsules or
even wafer form. You need to start taking them daily,
start with 1-2 tablespoons and build it up till you get
results. Initially you may feel a little gassy. But doing it
gradual, your body will get used to it.
Some cases, a mild antispasmodic medication may be
helpful taken 30-45 mins. before you eat. Drugs like
Hyocyamine or Dicyclomine are helpful. You can ask
your doctor about these. These will have side effects in
higher dosage like very dry mouth, blurred vision or
constipation. So, you have to watch for those.
I wish you well.

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