Weed is used to stimulate the appetite in other patients who won't eat and it's very effective.
Plenty of water and juice with vitamin and mineral supplements. Try those Innocent smoothies that come in bottles or cartons; you don't need a lot because they're absolutely full of sugar and made of nice, yummy fruit.
Imodium (loperamide) will help, a little bit, and really eating might seem like a huge hassle when you just don't feel any way about it—food just doesn't interest you and can even make you feel very uncomfortable and potentially nauseous despite having not eaten. Basically: force yourself. Maybe get some crisps or sweets or anything that has precious fats and sugars that you need without taking up much space or requiring much effort.
If you don't eat for long enough, you're going to feel even worse: no energy, no sleep, strange noises and hallucinations, etc. It's really very difficult to conduct a life, particularly if you've a job or need to interact with people often, whilst undergoing withdrawal. Still, I'm sure that you'll be able to get through it. Just try to relax whenever you can, for sleeping is not going to be easy.
Force yourself to eat. Hell, drink chocolate milk if you have to or eat jam straight from the jar...