Brief Answer:
he needs immediate medical attention right away..

Detailed Answer:
Hello XXXXXXX XXXXXXX Welcome to HCM,

I've gone through your query and understand your concern for your brother..

Please don't panic XXXXXXX but do note that your brother needs immediate medical attention..

Hemoglobin of 5.5 is not a sustainable situation for human body, even if he's looking fine and on Holiday, still he needs immediate medical attention for further evaluation to look for the cause of anemia (a Complete hemogram, Peripheral blood smear, Reticulocyte count, Urine routine microscopy, stool for OBT, LFT, Chest X-ray and/ iron profile etc.)..

Let me know if any of these investigations have done already and if yes then please upload them at the reports section so that I can have a detailed look..

Diabetes, if already diagnosed, can be looked in details subsequently after these work-ups, meanwhile my advice will be to take him to your nearest hospital/ER for a prompt clinical evaluation and investigations and if symptoms are severe then blood transfusion also..

So I wish you can understand that this not a condition which can be controlled with some syrup..please do not panic, but do the needful without any further delay..

Let me know if there's any further query, I'll be glad to clarify..

Let me know how he stays in the due course..

Take Care
Kind Regards

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