dog-tired
1. [ adjective ] drained of energy or effectiveness; extremely tired; completely exhausted
Synonyms: exhausted fatigued played_out worn_out spent worn-out washed-out fagged
Examples:

"the day's shopping left her exhausted" "he went to bed dog-tired" "was fagged and sweaty" "the trembling of his played out limbs" "felt completely washed-out" "only worn-out

Related terms: tired