I'm not sure if this is the right forum, but I'll give it a go.
About 5 days ago, after a quick snack my face began to swell. I've had this happen once before, so I knew to take some antihistamine, but within minutes I couldn't swallow, so I went to the hospital to get checked out. They said it did appear to be an allergic reaction and gave me a different antihistamine (phenergen) but as my vitals were OK said I could go home, but to keep taking the phenergen which I have been, 2 or 3 times daily since. In the days that followed, my facial swelling got better.
Yesterday after lunch my face swelled again, so I'm not sure if its something I'm eating which is causing this. I took an extra phenergen (making the total for the day 3) and it didn't get any worse, but is still there today. I went to the GP this morning and he gave me a prescription for prednisone which he said would help the swelling to go down. He said if it didn't work or got worse I was to go to the ER again. I took the prednisone about 3 1/2 hours ago. The swelling is still there, I can't tell if it's any better yet. Not worse fortunately.
My question is, how long should the prednisone take to work, and when should I consider going to the hospital again? I'd rather avoid the hospital option if possible.
You really need to identify what is causing this reaction. You should contact an allergist for help. It would also be helpful if you were to keep a journal of your diet and other things you were exposed to and a record of symptoms. If you can, go back and reconstruct the last week or so as accurately as possible. This might shed some light on what is causing you to react.
Feel better.