Hi Lesann

Welcome to NT. Hope you can find some answers to the cause of your PN.
As there are more than 100 different types of PN and just as many causes it may help if you can tell us the names of the antihistamines (including the allergy shots) and any other medications you may have taken. eg antibiotics

PN is a well known side effect for several different types of medications.

Also you can use the search function at the top to find other threads/posts about specific medications.