I have went through this problem 2 times in 2 years. With my experince with it you are supposed to give them one dose then give them another dose 2 weeks later and then one more dose after that 2 weeks later. a total of 3 doses 1 every 2 weeks. My geckos had Round worms. The fist time they had round worms (around 2 years ago) they were given a deworming medication that didn't work i don't remember the name. Then they were given panacur the way i described it up above then they successfully got rid of the worms. Then they got worms around 4 months ago they i took them to a vet and had a fecal exam done and they had round worms again. I asked the vet to prescribe panacur and he did. gave them the treatments again as prescribed and they have been completly dewormed again. And yes they do lose their appetite for a short amount of time but a couple days after treatment they should eat. IF they don't start eating again i would advise to take a fecal sample back to the vet to check to see if they have gotten rid of the worms after all 3 treatments. IF you have any more questions on deworming you can ask cause i have had experince with it. Also i have found out mine got the round worms from the live pinkies i had fed them. Which i will never feed live pinkies to my leos again only frozen/thawed pinkies.
1.2 Bearded dragons (Login, Raven, & Jean Grey) 1.1.1 Corn snakes(Havoc,Sable, & Kink0 1.5 Leo's (Psyloke (Lucky-male) Speedball, Domino, Rouge, Siren, Elektra) 1.0 Veiled Chams (Neo), 0.1 Rose Hair T. (Night Crawler) 0.0.3 Crested Geckos (Shiva, Storm, Beast) 0.2 Kenyan Sand Boas (Tigra & Cloak)