talk to your doctor about the medication you were perscribed and ask if its harmful to the baby, and if it is harmful ask if theres a medication you can take that wont harm the baby.
Try eating apple sauce and some soft fruits to keep your metabolism up, try a fruit salad, its soft on your throat.
OH! What about making a fruit smoothie and blueberries, raspberries, strawberries..all fruits that have antioxotains in them that are good for you and the baby.
Try to eat what you can, stay hydrated like your doing now, drink orange juice, its good for you too:)
But maybe give your doctor a call and ask him if the perscription is ok to take.