I can't comment on the re hydration aspect, but I can tell you a little about the bugs. I spent 2 years in Panama in the infantry. We spent a lot of time in the jungle and we tested Vit B Complex to see if it help with the bugs. We found that taking enough to change the color of your urine to yellow or orange helped a great deal.We ended up starting to take the B complex a day or two before we into the jungle and combined it with repellant on our uniforms. We could watch mosquitos land on a sweaty arm and take off without biting.
The B complex worked for about 80% of those who tried it.
We also found that some commercial repellants tended to attract bugs to a few people..This wasn't a scientific study, but we all felt that the results were valid and we continued to use B complex. Don't try to dissolve the B complex in water and drink it, it tastes really bad.