when i have given my kids the teething drops, I have given them the 4 doses - 1/2 an hour apart, and then four hourly if needed. If you let it go more than the 4 hours - i.e the next day, then you need to do the 4 doses at 1/2 hour intervals again. I found that by the time i get to the 3rd dose they have settled them right down.

good luck with teething!!!!