I was just testing if endermen were also able to teleport away from tipped arrows (with effects).
As I was testing it (with a Tipped Arrow of Poison II for two seconds), yes, the enderman test subject teleported away (as expected), but the effect carried through the enderman!
Reproducing
1. (optional) /gamemode 1
2. Shoot at the enderman with any tipped arrow effect.
Results
Expected
The effects should not carry through the enderman.
Observed
The effects carried through the enderman.