If you've ever worked with toxic people, you know that dealing with them can be mentally, emotionally, and physically taxing.

One recent poll of 800 managers and employees in 17 industries, as reported by Harvard Business Review, found that among employees who've been on the receiving end of negative behaviors like manipulation, bullying, and inappropriate use of power:  

  • 48 percent intentionally decreased their work effort.
  • 38 percent intentionally decreased the quality of their work.
  • 80 percent lost work time worrying about the incident.
  • 66 percent said that their performance declined.
  • 25 percent admitted to taking their frustration out on customers.

Manipulative people are among the worst. 

Among the most toxic coworkers or bosses you'll find, manipulators are especially tough to deal with. The worst kind of manipulator will do anything to shake your confidence, make you feel stupid, uncertain, and second-guess yourself and your worth.

Manipulative people love to plant seeds of doubt to keep you unfocused so they can take what they want from you. They manipulate you into believing that their opinions are objective facts, and that you're the one who's crazy or inadequate.

They'll tell you how to live your life according to how they think it should be lived. And if you don't heed their advice and make changes the way they want you to change, you're doomed to fail. 

The most dangerous aspect of a manipulator is control -- they want to control you to validate their low self-esteem and keep you from outdoing them at work or in life. Don't get conned into thinking they care about you or your interests. They may sound like they are, but manipulators are only worried about their own.

To counter the schemes of manipulators roaming your office hallways, displaying your confidence is key to eliminate unwanted behaviors. Put these strategies into place to send the message that their toxic manipulation will not be tolerated. 

1. Stiff-arm them with a confident comeback line.

A manipulator will usually try to dictate your emotions and tell you how you feel to get you to respond defensively with anger, fear or sadness, which plays right into their need for control.  By having a self-assured come-back line in your verbal arsenal when they attempt a manipulative attack, it will stop them dead in their tracks. Try this: "I reject your assessment of my emotional state." This come-back validates your own self-worth and sends a strong message that you cannot be controlled.

2. Diffuse their anger with a calm demeanor.

Some of you might think that will just tick them off, right? Perhaps, but certain manipulators thrive on on drama and want to start a confrontation to draw out your emotional state and suck you into theirs. Don't fall for it. Rise above it by reducing their anger before you engage in conversation. Here's what to do: Respond calmly with, "I'd like to request that you calm down before we start discussing this issue, or I'm walking away." This sends a clear message that you won't be trampled on. It will also control your own urge to react to an attack with an attack -- a sure way to keep your 'best supporting actor' role in their pathetic drama.

3. Simple ignore them.

Before you choose to get worked up (which is what manipulators want), an even better approach is to resist the urge to engage with them by ignoring them. While doing so may be infuriating for the manipulator, you'll condition them to accept that they can't change your emotions and will soon move on to another target.

4. Reject their flattery.

Consultant Liz Kislik writes in Harvard Business Review, "refuse to keep secrets or to act as interpreter in ways that normalize underhanded behavior." She adds, "These schemers may treat you like a trusted insider, feeding you tidbits about other people's inadequacies and failures, as if only you have the perspective and discretion to understand what's important. Don't be taken in by the implied flattery." To put a monkey wrench in their mechanism, Kislik says we should ask for details and specifics to flush out their intent. For example: "I'm not sure I understand what you mean. Why are you telling me this? What is it you're asking me to do?"

5. Remember that you are not the problem.

Being ensnared by the manipulator's agenda may cause feelings of inadequacy and self-blame to surface. In these situations, Preston Ni writes in Psychology Today, "it's important to remember that you are not the problem; you're simply being manipulated to feel bad about yourself, so that you're more likely to surrender your power and rights." Ni says we should assess the health of our relationship with the manipulator by asking ourselves:

  • Am I being treated with genuine respect?
  • Are this person's expectations and demands of me reasonable?
  • Is the giving in this relationship primarily one way or two ways?
  • Ultimately, do I feel good about myself in this relationship?

"Your answers to these questions," writes Ni, "give you important clues about whether the 'problem' in the relationship is with you or the other person.