Calamine
"I had rash due to an allergic reaction to prescibed medication that was so aggressive I was covered head to toe in 35 hours. First trip to ER netted me prednisone, Benadryl and Zantac which helped with the swelling but not the crazy itching! After another 40 hours of trying not to scratch I went back to ER because the rash was still spreading and I was needing a straight jacket for the itch. New antihistamine prescribed and told to get some Calamine lotion. The pink stuff from when you were a kid? Yep. 

In the car and slathering pink all over my arms and I am finally getting a little relief. Begged Mom to rub it on my back. THE RELIEF!!! 

The new pill helped too but I will never underestimate the power of the pink stuff. $6. Thank you GOD."