Thanks for your question.
You have probably got a reaction to the clarithromycin.
Your pharmacist has advised to take benadryl and its ok to take. Nothing else is possible at home. You should continue to take this in a dosage of one tablet twice daily.
Observe your symptoms and see if they increases, visit ER immediately as you will be in need of a steroid shot but since sometime has passed since you got the reaction hopefully it will not increase further but please keep observing yourself very closely.
And go to your doctor to have an examination done at the earliest.
I hope this helps you.
Please ask more if you want or click ACCEPT if i have answered your question
Thank you very for your help.
Catnip you are most welcome
i wish that you get well soon