In bold, bright red lettering, a full-page advertisement in Tuesday’s Boston Globe warns readers that elderly nursing homes residents in three HealthBridge Management-owned Massachusetts facilities are given antipsychotic drugs at rates much higher than the national average -- despite federal warnings about lethal side effects from the powerful sedatives.

The ad was paid for by 1199SEIU United Healthcare Workers East, a union that represents thousands of workers in five states, including Massachusetts, and is affiliated with a labor group battling Healthbridge in six Connecticut nursing homes.