Hello dear, surely will help you. See, better not use medicine for increasing weight as they have side effect. We ise food as a medicine to treat diseases. There are many reason of being underweight. 1. Endocrine disturbances 2. Genetic 3. Vitamins and minerals deficiency 4. Psychological problem 5.IBS 6. Eating disorder 7. Liver dysfunction And many more   So my opinion is to contact directly to us so that we can find the cause of weight reduction , gathering all your data and according ly we will suggest you.