Euro 2012 qual. - Earnshaw out of Wales squad
The 29-year-old, who has scored 14 goals in 51 internationals, has missed Forest's last three Championship games with a thigh injury and will not join up with his international team-mates.
Wales face Bulgaria at Cardiff City Stadium on Friday before travelling to Basel to play the Swiss the following Tuesday.
Caretaker manager Brian Flynn has called up Southampton forward Ryan Doble, 19, as his replacement.
Doble has been already been capped at under-17, under-19 and under-21 level for Wales but has yet to make a senior appearance for Saints.
Norwich midfielder Andrew Crofts has also been drafted into the club.
Crofts has been a big hit at Carrow Road since his summer move from Brighton and has been called up in place of injured Doncaster midfielder Brian Stock.
The Welsh will face Bulgaria at Cardiff's new stadium on Friday night before flying out to play Switzerland on Tuesday, October 12.