The employee you have come to know and trust usually performs as expected and shows up in a way that is productive for the entire team. But over time, or even just occasionally, you are seeing someone whom you don't recognize.

I recently wrote about coaching versus counseling, but this question was asked by numerous readers: "How can you tell when an employee needs coaching, and when he needs more serious help?" Don't get me wrong, but coaching can be serious help. However, I think what you are actually asking is: When does an employee need professional psychological help based on the observation of a significant change in behavior?

According to the National Alliance on Mental Illness (NAMI), a mental illness is a condition that impacts a person's thinking, feeling, or mood and that may affect his or her ability to relate to others and function on a daily basis. Each person will have different experiences; even people with the same diagnosis will react differently. As an employer, your job is not to diagnose or be intrusive, but rather to create an environment wherein all employees feel a sense of security. There are early-warning signs that are observable and can suggest that something more serious is occurring. I believe you will be able to tell if an employee needs professional help by his actions and behaviors that impair his day-to-day activities. Here are three primary behaviors that you should be concerned about.

1. Playing the role of Houdini.

A person with a mental illness may ordinarily be reliable to a fault, but when experiencing an episode he may appear to pulling a disappearing act. The employee may miss work for hours to weeks without any excuse or explanation. This may be due to a diagnosed or undiagnosed mental illness such as anxiety disorders, mood disorders, psychotic disorders, impulse control and addiction disorders, personality disorders, or even post-traumatic stress disorder (PTSD).

However, before we label someone as mentally ill when they disappear, keep in mind that some people may be experiencing financial, marital, or work-related issues that are so overwhelming that they just need and want a time-out, and run away as a form of escape. In any case, this can be disruptive to an organization, and needs to be addressed by speaking with the employee.

2. Going from zero to 60 within seconds.

A person who may need professional help is often unable to control his emotions, especially when having an episode. If you notice that an employee is becoming agitated and/or irritated easily, especially when everyone else is remaining calm, you may want to take action. Negative behaviors such as an increased need to get involved in multiple projects by skipping from one thing to another, taking on risky business ventures without considering the risks, and exhibiting signs of restlessness are additional telltale signs that something is going on with that employee.

These are just a few of the many things that you may notice during the 9-to-5 day. But there are also the grandiose thoughts, over-socializing, talkativeness, and behaviors that appear giddy one moment and brooding the next that should give you a sense that the employee may need help. In short, if you engage an employee and you notice that everyone is looking bewildered by his behaviors, whether good or bad, you may want to inquire about how he's feeling. Unfortunately, when there is some form of mental illness, the person afflicted will be unaware of his behaviors. It is common for people who have a relationship with that employee to notice something amiss long before the employee himself recognizes a change in his behavior.

3. Presenting an abnormal appearance.

This can run the gamut from looking disheveled to actually acting high. When an employee is experiencing mental health challenges, especially undiagnosed, you will notice a difference in his appearance. This may mean that he isn't taking care of his personal hygiene, e.g. shaving, grooming, etc. It may also mean looking as if he hasn't slept in days, which may actually be the case. Some mental health disorders cause people to get little to no sleep.

Then there is the foggy distant look, indicating the employee may be high from self-medicating. It is not uncommon for some people to abhor actual medication from a psychiatrist but rather partake in marijuana, Vicodin, cocaine, caffeine, or alcohol to soothe his nerves or calm his mind. Regardless of an employee's drug of choice, you may see in his eyes and behaviors that he is in fact high as a way of escaping from depression or other feelings and emotions that he doesn't want to deal with.