My favorite blood substitute is a sort of tea/juice mixture. It dosen't do the same thing as feeding, but it will reduce rage and discomfort for a while. It takes some getting used to the taste, however.
Start with 2 cups cranberry juice, and set them aside. Pour two cups of springwater into a NON METAL container on the stove and heat on "low". Add 1 tsp. cumin, 4 Tbsp. honey, 1 Tbsp dried and ground rosehips, a pinch cinnamon, 1 tsp. rosemary, a bay leaf, and some dried orange peel. Cook together until the water smells strongly of the herbs, then let cool with the herbs still in it. When cool, strain out the herbs and mix with the cranberry juice. If available, add fresh strawberry or cherry juice, or just eat the fruits whole while drinking.
Another mix is not nearly as good for your teeth, but also helps the hunger and your craving for sweets. Take 6 scoops instant hot chocolate and put in a glass vessel. Add 4 cinnamon sticks, a tsp. cardamon, 1/2 teaspoon nutmeg and a teaspoon instant coffee crystals. Add 2 and 1/2 cups hot water, and some hazelnut flavored creamer (the same amount as for 1 cup coffee). Mix and enjoy while hot.
Also try "Red Zinger" tea by Celestial Seasonings Co. with lots of honey, Freshly squeezed orange juice, or the following for those who can stand it. This one is great if you are really close to frenzy, as it tastes awful but works well. Get a 2 serving container of prepackaged tomato or V-8 juice (one of the drinkable vegetable/tomato based concoctions) and open it. Pour into a blender. Add 3 Tbsp black freshly ground pepper and 1 Tbsp. Cayenne pepper. Blend until well-mixed and add 5 drops lemon juice. Now choke it down if you can, and it honestly will ease the hunger (as well as killing tastebuds by the hundreds). Quickie hunger aids are fresh fruit, a pinch of salt on the tounge, an ice cube melted in the mouth, ice cream, strawberry and chocolate milkshakes, and any dark or milk chocolate.