Hi, surely will help you. See, there are many reason of not gaining weight. . Endrocrine problems . IBS . Dietary problem . Liver problem . Tuberculosis . Vitamin and minerals deficiencies . GI (Digestive)problem . Improper sleep . Stress And many more HOW WE TREAT Underweight thru DIET . Find the main cause and Deficiency which cause hidderence in weight  gain . TREAT the cause first. . Increase your appetite . Reduce the Deficiencies occurring in the body thru diet . And at last you will easily gain weight without much effort. So, better to consult through the link below,so that  we can discuss in detail and suggest you accordingly.

You need to take worm medicines. Consult nearby physician. And check your haemoglobin. Take high protein diet and balanced nutrition. Contact me through practo direct consultation for further information

You can do antiworming course of medicine for treatment and share your details about Health parameters and daily routine and food habits and physical activity level along with Health issues for assessment and further guidance.