Brief Answer:
Such symptoms can occur due to some medical and psychiatric conditions

Detailed Answer:
Hello thanks for asking from HCM for your health related queries

I can understand your concern. You are a healthy 24 years old male with symptoms like persistent tiredness through out the day, inability to concentrate, loss of weight, insomnia etc. Such symptoms can occur in a number of conditions both medical and psychiatric.

- One most common reason for such symptoms is low levels of Vitamins in body especially of Vitamin B12. I would advise you to get your B12 levels checked to rule out the condition. Low vitamin B12 levels are associated with tiredness, fatiguability, poor concentration and symptoms of anxiety. If levels come in lower range start taking B12 supplements and take them for at least 6 months.

- Other possibility is anaemia. Anaemia can also present with such symptoms. Get you haemoglobin levels checked to rule out anaemia.

- Hypothyroidism is other medical condition that can present with persistent tiredness, inability to concentrate, drowsiness etc symptoms. But other symptoms like weight gain, reduced appetite, cold intolerance etc are also seen. To rule out subclinical hypothyroidism get your thyroid hormone levels checked.

- If common medical conditions are ruled out then such symptoms can occur due to mild depressive episode also. Altered sleep pattern, tiredness, feelings like lack of energy, poor concentration at work, loss of weight etc symptoms are commonly seen. I would advise you to consult a neuropsychiatrist for proper evaluation of these symptoms. Low doses of drugs like Modafinil or Armodafinil can help to reduce the symptoms of tiredness and you will feel better.

Following lifestyle changes will help in your symptoms apart from medicines-

Apart from B12 supplements I would also advise you to take Omega-3-Fatty Acids, these supplements will improve your activities and will reduce tiredness.

Take diets rich in proteins and complex carbs and low in fats. This will help to improve the concentration.

Exercise daily and improve sleep hygiene for good sleep. All these life style changes will help to improve your symptoms.

Thanks, hope this helps you. Please ask again for more doubts.

Take care

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