That's exactly what my doctor prescribed:

1st take the Benadryl.

Then take a Zirtec for longer relief.

Then take Prednisone for longer term reduction of swelling.

If at any point you notice the symptoms of anaphylaxis, inject with the epipen. And be prepared to do that twice after the first one wears off.

And get to medical attention ASAP. Which might be a bit of a challenge 18 miles into a backpacking trip...
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