I had a sore throat for the first couple of weeks, but it did pass. These things helped me:
1. Stop inhaling for a few days - the nicotine is absorbed through the mouth anyway so inhaling is not necessary. I do like to inhale though, and can do so now no problems.
2. Take cough medicine to soothe the throat.
3. Drink plenty of water.
4. Switch to a juice with a higher VG content.