[Adilegian]

Regular Speedstick works for me.

Also, depending on your wardrobe, you might consider buying two pairs of the same shirt with you if you anticipate getting gross. When you're done with whatever's making you sweat (work or just being in humidity) you can find a public bathroom, pull the duplicate shirt out of your bag, and swap them out.

Though, if you take this route, I also recommend putting your sweaty shirt in a grocery bag to help keep the inside of your bag from getting mildewed.
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