Sorry to hear he isn't doing any better, I think it may be time to try and find an exotics vet. In the mean time I believe something else is putting him off food, if you could fill these questions out the best you can it may help us determine if there is and what is making him not want to eat.
1. Size of enclosure
2. # of inhabitants - specifically other frogs and size differences
3. Humidity
4. Temperature
5. Water - type - for both misting and soaking dish
6. Materials used for substrate
7. Enclosure set up i.e. plants (live or artificial), wood, bark and other materials.
- How were things prepared prior to being put into the viv.
8. Main food source
9. Vitamins and calcium? (how often)
10. Lighting
11. What is being used to maintain the temperature of the enclosure
12. When is the last time he/she ate
13. Have you found poop lately
14. A pic would be helpful including frog and enclosure (any including cell phone pic is fine)
15. Describe frog's symptoms and/or recent physical changes; to include it's ventral/belly area.
16. How old is the frog
17. How long have you owned him/her
18. Is the frog wild caught or captive bred
19. Frog food- how often and if it is diverse, what other feeders are used as treats
20. How often the frog is handled
21. Is the enclosure kept in a high or low traffic area
22. Describe enclosure maintenance (water changes, cleaning, etc)