A duhggen is a dog that has old man features. Most commonly seen in scottish terriers and sometimes irish wolf hounds. Duhggen can also be used in many different situations and can also be a name for a person you really like.
Taken from its paralleled alcohol counterpart the DUI, a DUHigh is a driving-related offense due to excess levels of marijuana in the driver's system. Although weed does not impair driving abilities as drastically as alcohol, some people still can't handle the pressure and get pulled over, whereupon the officer realizes the driver is high as shit and arrests him for a DUHigh.
Passenger: Dude, why are you going 15 MPH in a 35?
Driver: I'm high as a kangaroo on a trampoline yo, I feel like I'm going 60.