Never workout immediately following allergy shots

What happens when you get an allergy shot before arms day at the gym.
Apparently shots don't mix with handstand pushups. 

Never work out immediately following an allergy shot or four.

For some reason, I thought my allergy doctor said it was fine to workout after getting my shots. I've gotten my shots in workout clothes, even told the nurses I was going to go workout. And I have before. I got an allergy shot after work, say 5:20 and then headed to the 6 p.m. class at the gym and had no reaction.

Today, I got an allergy shot after 5, headed directly to the 6 p.m. circuit training class—and my arm broke out into a giant itchy welt.

I didn't actually notice it until I got home around 8 p.m. But it was massive. I put hydrocortisone on it, took a pictures for the doctor and vowed not to do it again.

But, you're really supposed to wait about two hours after a shot to work out—otherwise there's too much blood flow to the tissues and cause the allergens to get into your blood faster. (Thanks WebMD)

So now I know! And from now on, only lunch time shots if I'm working out in the evening.