No one wants to be accused of being a narcissist: someone with an excessive interest in themselves. But how can you tell if you (or someone you know) is a narcissist? When does self-interest become self-limiting? The answer lies in knowing the difference between healthy and unhealthy narcissism.

We all have narcissistic tendencies—which isn’t a bad thing, says Dr. Craig Malkin, a Harvard Medical School lecturer and author of the internationally acclaimed book Rethinking Narcissism: The Secret to Recognizing and Coping With Narcissists. In healthy doses, narcissism creates our drive to stand out, and this drive helps us to thrive. “These rose-colored glasses help us to be more resilient, persist in the face of failure, and feel ambitious. It’s okay to feel good and dream big,” Malkin says.

However, narcissism becomes unhealthy when people become addicted to feeling special and will do whatever it takes to feel this way. Despite the caricature as a chest-thumping egomaniac, many unhealthy narcissists see themselves as unique because they think their emotional pain is more important than everyone else’s. They suck the air out of a room, demanding attention or praise while offering little in return. Think of the teenager whose break-up is the worst ever, the stressed-out boss who consistently takes full credit for the work of the team (yet shirks responsibility when things go wrong), or the friend who acts like their life is always perfect and protects this image at all costs.

If you’re connected to an unhealthy narcissist, whether in your personal or professional life, Malkin suggests using empathy prompts to underscore the importance of your relationship. The goal is to shift the focus from “you and me” to “we.” Here are three hallmarks of unhealthy narcissism and how to handle them:

1. They’re afraid of emotions. At the root of unhealthy narcissism is insecurity. Narcissists try to boost their self-confidence by imagining that they’re completely self-sufficient and unaffected by feelings. They can’t feel vulnerable. If they’re hurt or upset, they lash out in anger and become condescending, pointing out the other person’s flaws. By masking their hurt with anger and bluster, they can avoid feeling discomfort. Think of the friend who simply changes the subject or gets huffy, trivializing your needs each time you bring up a difficult topic.
How to cope: Use empathy. Say, “You’re my friend. When you lash out at me, it hurts me and derails the conversation. Can we try to talk about this in a calm and respectful way?”

2. They exert stealth control. Unhealthy narcissists need to remain in charge. They feel uneasy asking for help or making their needs known, because they’re afraid to depend on people. Think of the pal who always cancels plans at the last minute instead of simply saying she’d rather do something else, or who becomes quiet when you suggest what you’d like to do, then steers the conversation back to what he or she had in mind.
How to cope: Tell them how you feel. Say, “When you cancel our plans without warning, it makes me feel sad, like I’m not important to you.”

3. They play “hot potato.” Unhealthy narcissists fear emotions, and emotional hot potato lets them pass those emotions on to someone else—like you. They engage in projection, denying their own feelings and assigning them to someone else. Think about the coworker who avoids you for days and then says, “Are you mad at me?” Rather than confronting her own possible angry feelings, she accuses you of having them instead—which might make you pretty mad, right? By doing this, an unhealthy narcissist coerces you into experiencing their emotions, so they don’t have to.
How to cope: Let them know they matter. Say, “Our relationship is important to me. When you don’t reply to my messages, it makes me feel concerned.”

Ultimately, the only person who can change an unhealthy narcissist is themselves—but by being able to spot the warning signs, you can take steps toward nudging them into healthier interactions.

Kara Baskin is a Boston-based journalist who writes about food, health, well-being, and lifestyle for The Boston Globe, Boston Magazine, Women’s Health, and AARP’s Life Reimagined. She’s also the author of “Size Matters: The Hard Facts About Male Sexuality That Every Woman Should Know” (Random House). Find her on Twitter @kcbaskin