Hello,
Thanks for posting your query.
A low normal body weight with frequent stomach aches is suggestive of poor food intake making him weak and lethargy.
Pain abdomen in children is most commonly an intestinal colic. It happens due to immature intestines and starts as soon as the child consumes anything.
Other reasons for abdominal pain may include constipation due to less capacity to digest the food material by their intestines.
Some children may produce gas in stomach and so in intestines; that may again lead to develop abdominal colic or pain. Children should not be overfed as it may result in vomiting and gastro-intestinal disturbance.
Anti spasmodic drops may be given in restricted doses for immediate relief.
There are some home remedies like giving less than one milliliter of ginger juice and a very little pinch of rock salt. You can also give your child the holy basil’s juice, which is very effective most of the times.
To rule out the presence of any organic cause, you can go for ultrasound scan and X-ray of abdomen erect under the guidance of your pediatrician. He will also rule out malnutrition and will prescribe the appropriate supplements required after a detailed examination.
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Wishing you good health.
Regards.

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