If a bizarre-behaving colleague isn't someone you're close with, there's a decent chance your offer to "talk" and lend support will be rebuffed. That's when it's time to alert a supervisor to your concerns, King said. (For those who'd rather not get involved, King points out that many employers have a substance abuse policy requiring workers to let management know if they learn someone is using at work.)
Julie Le Blanc, associate director of clinical services at Harris, Rothenberg Intl., which provides employee assistance program counseling to 2,800 companies, agrees with kicking your concerns up the food chain. This becomes imperative if you're worried a co-worker might physically harm himself or others -- for example, if they start talking about suicide or become violent.
"Any time there's any potential perceived or real danger, people have to report it," Le Blanc said. "That's why you have that gut instinct. If it doesn't feel right, go to a person of authority and say, 'It might be nothing, but here's what I saw.'"
Managers: Focus the Conversation on Performance
For the sake of argument, let's assume the person in question isn't a perceived physical threat to themselves or others, just a professional train wreck. Since erratic behavior often goes hand in hand with compromised job performance, and in some cases, decreased morale among other employees, managers can't just turn a blind eye.
When confronting someone you're supervising, Le Blanc advises leading with the uncharacteristic behavior the person has been displaying. (A direct "I've noticed you coming in to work 90 minutes late and wandering the halls aimlessly this past week. Is everything OK?" should do the trick.) Don't chastise, penalize or guess what the problem might be. Instead, Le Blanc said, tell the co-worker you care and want to support her but that you're worried a problem at home or at work is affecting her ability to do her job. If appropriate, remind them of the relevant benefits your company offers -- counseling, employee assistance hotline, paid time off, short-term disability and the like.
After conferring with her HR department on how to proceed, Gabor Hawkins had a conversation like this with Miranda, her employee who'd been foundering after her medical crisis.
"We talked a long time," Gabor Hawkins said. "I did not make it personal. It was all based on her job duties and her not meeting them. I told her I thought she would want to know so she would change. There were tears and she knew her job was on the line. I was firm, but she knew I had her back and was there to help."
For the next month, Gabor Hawkins closely tracked Miranda's output and met with her weekly to ensure she was on top of her deadlines.
"Within a week or so, she became the employee that she was before," Gabor Hawkins said. "I think it helped that we had a good relationship. She knew I wanted her to succeed. And I knew she could."
This work is the opinion of the columnist, and in no way reflects the opinion of ABC News.
Michelle Goodman is a freelance writer and former cubicle dweller. Her books include My So-Called Freelance Life: How to Survive and Thrive as a Creative Professional for Hire and The Anti 9-to-5 Guide: Practical Career Advice for Women Who Think Outside the Cube. Follow her at @anti9to5guide.