I am 25 years old female with no other symptoms. I had this hive like rash appear on the top of my right hand only. Has not spread, just gotten a deeper red color. Has some scab like areas I think because I scratched it at first. Does not itch anymore. Have not used any new products or exposed to any allergens. I am aware of to cause this. Again, only on my right hand. This is the fourth day of this rash. Have no idea what it could be from. I have taken Benadryl once daily, it had no effect. Also, have applied Hydrocortisone with no effect. Please help.