When Should I Replace a Bottle of Sawyer Permethrin Spray

I have a bottle of Sawyer pre-mixed Permethrin spray that has been sitting in my home for a couple of years (never colder than 65F, never hotter than 83F).  Is the active ingredient still “active”?  Or should I replace it to be safe?

I don’t want to fool around, because I’m planning a trip to Lyme-Disease-central (Vermont), and I’d dearly like to complete my trip without getting bitten by a tick!

Edited to add: I have all the original packaging, and nowhere is there an “expiration date”.

Send a email to johntsmith@sawyerproducts.com concerning your question. I believe the FORM would like seeing the reply when you receive a return from the email

Great idea, thanks, Ken!!!  I have sent the email; being a holiday weekend, I don’t expect an answer for a while.

Well, that’s the best customer service I’ve ever experienced — he answered (Sunday of a holiday weekend).  Here’s the answer:

John Smith <johntsmith@sawyer.com></div>
Sun 5/27/2018, 5:07 PM</div>

The permethrin lasts about 10 years. Look at the color after shaking well, if it’s white its good – brown to black it’s bad.  You need 4 oz on an outfit or it’s not going to be effective.