What Is The Treatment For Itchy Scalp?

my whole house hold started having very itchy scalps about 2 to 3 weeks ago (2 1/2 yr old son, 10 yr old son, 74 yr old grandmother and myself 31 yr old female) we all do not share the same shampoos or hair products, brushes etc. its getting worst I find my youngest itching his head while asleep at times, its driving me nuts I get so itchy, I noticed yesterday I have small tiny bumps where I am itchy on my scalp they are not any different color compared to my scalp and I am the only one with the bumps, we do NOT have lice or anything or the sort. Tried head and shoulders shampoo on all of us, t-gel shampoo as well. what could this be and how can I stop the itching on out scalp. Please help. Tiffany, Ohio.