I've been using Valbazen and Safeguard for years and we eat the eggs after using either product. Still here typing. Besides, Albendazole is used in humans as a wormer.
There's no need to worm your whole flock when it comes to tapeworms, unlike roundworms. You only have to worm the birds that have segments in feces. You can use a black magic marker to mark the combs by process of elimination of which birds have a the segments and the ones that dont. You might...