I know what your going through. My daughter had an earache July 16 2009, and i took her to the doctor that same afternoon. and she was prescribed amoxicillin. the next day we saw small rash, at first we thought it was just a bug bite but it was getting worst. I took her back to the doctor and they told her to try Zyrtec and that did not work either. I did alot of researching myself on the internet and tons of reading how to help her with her rash, i tried aloe and at first it looks like it was helping but the rash was the same, the the itch was not as bad. Then I tried the ''BAG BALM" it is used for healing blisters for Gymnast as my daughter is a gymnast. I would put bag blam on her rash then wrap bandaid on it. I kept doing that for 2 days straight and i started to see a difference. the rash that was on her chest was disappearing, it was 7 rash total on her chest and now its only 2 and i see its healing. oh before i forget, she was taking Benadryl also once in the morning and once again before bed. I give her 3tsp each time. It help her. I still did an appointment to her doctor today and saw her doctor and told her what i have been doing, but he know about amoxicillin could cause rashes and after i told him what i had tried, he prescribed my daughter "HYDROXYZINE" 10mg/5ml SYRUP....and "DESOXIMETASONE 0.05% CREAM 15GM.
i gave it to her at 6pm because i knew she was going to bed at 8 pm and wanted to see if the medicine affects her at all like sleepy or etc....and she did not, like she does not feel sleepy as well when she takes benadryl. Anyways, after i gave her 1 1/2 tsp of the syrup medicine, i applied the cream on her rash, and after 1 hour, i checked up on her rash and i right away saw the difference. she is now sleeping, and i will check again tom. and I'm crossing my fingers that the medicine will work this time and fast, if not I know the "BAG BALM" works even tho it took couple of days for slowly disappearing its working. Its a green can container that you can get from walgreens pharmacy. Its up to you if you want to try it, just letting you know it works for my daughter who has rashes on her arms, chest, legs. email me email@example.com if you want to know about her result tom. morning just incase i don't find this site to tell you. Good Luck and I will pray for your kid.
PS. My daughter took first shot Gardisal June 22nd 2009, then amoxicillin july 16 2009.
Rash Reaction July 17, 2009.