Both Tea Tree Oil and Witch Hazel work great for getting rid of Fever Blisters.
Apply the Tea Tree oil or witch hazel to the Fever Blister a few times per day and the Fever Blister should be gone in 1 to 3 days.
You should also apply some ice to the fever blister which can help it heal.
Lemon Balm and Lysine also works for getting rid of Fever Blisters.