noun

Someone who is considered to be exaggerating a danger and so causing needless worry or panic.

the problem is a fabrication by alarmists

scaremonger,gloom-monger,doom-monger,voice of doom,doomster,doomsayer,doom merchant,Cassandra

adjective

Creating needless worry or panic.

alarmist rumors

gloomy,dismal,pessimistic,negative,defeatist,downbeat,gloom-ridden,cynical,bleak,grim,fatalistic,black,sombre,drab,dreary