Collect 7 Hyacinth Mushrooms, 4 Moonpetal Lilies, and 1 Webwood Ichor for Dirania Silveshine in Shadowglen.
We may be able to help Iverron, as I know of an antidote that should help with the poison. It requires some ingredients, though, before I can make it.
I'll need Hyacinth mushrooms. You can find these growing under trees, or you may collect them from the grell south of here; they seem to have taken a liking to them. I'll also need Moonpetal lilies, which only grow around watery pools.
The last ingredient may prove the most difficult. From the very spiders that poisoned Iverron, collect Webwood ichor.