Millions of workers from teachers to fitness instructors are losing their voices and costing the economy millions each year, says the TUC.
Call centre workers are among those at threat from voice loss
Germs, dry centrally-heated offices and jobs which require too much talking are to blame, says the Work Hoarse report.
The TUC warns bosses not to persuade sick workers back to work early and to make sure workers have decent breaks.
One in five teachers go off sick with voice problems, five times the UK average, says the report.
Other professions at risk include call centre workers, shop staff, radio and TV reporters, barristers, bingo callers and fitness instructors.
The report's author, Rory O'Neill, said: "In many service sector jobs, it is easy to forget the voice is working overtime throughout the entire shift - and that is dangerous talk.
"Whatever name you give it - repetitive voice injury, call centre-itis or the curse of the chalkface - it is a potentially career threatening condition."
The TUC wants companies to make sure employees drink plenty of water and that offices are free of dust and chemicals.
It says its research suggests the problem is growing and is costing the economy £200m a year.
TUC General Secretary Brendan Barber said loss of voice could become a serious condition which could end up costing workers their jobs.
He urged people to speak up when they first develop symptoms.