The parasites or the medication to treat them may also be affecting his appetite. It will probably pick up once he has finished the medications.
Stick with either baby food chicken or egg (hard boiled or scrambled) for protein along with fruits and vegetables until you get the ingredients to prepare the BML.
Once you are feeding BML - be sure to follow the directions and feed only frozen mixed vegetables each night and your choice fruit from those allowed on this feeding plan. (apples, grapes, watermelon, cantaloupe, honeydew, frozen pitted cherries, blueberries)
Here is the link for the full instructions for BML - Bourbon's Modified Leadbeaters.
http://www.bmldiet.com/bml-recipe.html