Generally speaking, OCD involves worry, often excessive and unrelenting. Usually, the anxiety is about the kinds of things most other people wouldn't fret about that much: fear that you've been exposed to a horrible disease, or a gnawing apprehension that you have not done something you should have (such as locking the front door) or done it well enough (such as writing a paper). If you or someone you care about has experienced something like this, take heart: Your problem has a name and many possible solutions.

You may have different worries: constant fear of personal attack or electricity, or a vague belief that your thoughts or actions can influence events. You may be tormented by bizarre unwanted sexual thoughts, or have a secret fear of harming someone — even a child or spouse you care about very much. You might feel a need to save or collect garbage, or to wash your groceries when you come home from the store. The thoughts and behaviors that can signal OCD really do run the gamut.

Obsessions

People who have OCD tend to obsess about certain things. These obsessions almost always stem from anxiety. The number of objects, situations, and places that people have been known to fear are nearly without limit. If you're terrified of electricity (or, conversely, of electrical appliances not working), cities, tall buildings, certain numbers or colors, vomiting, choking, blood, teeth, various animals, car accidents, or contracting AIDS, hantavirus, rabies, botulism, Ebola, avian flu, cancer, or any number of other serious diseases, you're not alone.

If you sometimes go so far as to do yourself harm trying to escape from the situations that frighten you (if, for instance, you sometimes wash or even gargle with chemical solutions), you're not alone.

If your fears sometimes seem to “cancel one another out,” (that is, if you fear for example, both diseases and the vaccinations that can prevent them — or the needles that deliver those vaccines); if you secretly worry that you'll shout out a curse word at an inappropriate time (or that perhaps you already have); if you often agonize because you think you might have accidentally hit a pedestrian while driving, even though you don't see an apparent victim; if your head is frequently filled with visions of terrible events; even if you worry about poison or other unwholesome substances in your food or water … you're not alone.

Compulsions

To compensate for these obsessive fears and worries, people who have OCD often perform compulsions — certain “rituals” they feel the need to carry out. For example, if you constantly worry about your car being stolen you might spend an hour each day just checking all the doors and windows to make sure all locks are completely secure. The amount of time you take performing your ritual can help a doctor evaluate whether you have OCD and, if so, how severe it may be.

Some OCD sufferers end up checking their stoves or door locks, washing themselves or their belongings, or praying against harm for hours at a time. Even 15 minutes spent making sure your front door is locked are about 14 and a half more than you need. The amount of time you give each day (or week or year) to obsessions and compulsions may provide a clue about whether you have OCD. Here are a few more examples of compulsive behaviors:

• Washing your hands so often that the skin routinely cracks and bleeds

• Feeling the need to shower after someone touches you — even after a simple handshake or pat on the back

• Avoiding communal objects that are touched by many people, such as elevator buttons, public computers, and library books

• Worrying that you might deliberately or accidentally hurt someone

• Habitually spitting things out

• Checking your clothing for insects before getting dressed

This is only a fraction of the possibilities out there. No matter what your obsessions and compulsions, chances are you're not the only person who experiences them.

Other Components of OCD

But OCD isn't just as simple as obsession and compulsion. There are other feelings, experiences, and behaviors that people who have OCD commonly exhibit:

• A feeling of powerlessness. You can't seem to gain control over your behaviors, however hard you try. The need to “ward off” unhappy consequences — or save stacks of magazines or empty boxes, or whatever your compulsion is — overwhelms the desire to relax and enjoy life as others seem to.

• The knowledge that, on some level, these behaviors are irrational. While it may seem as if avoiding the feared situation or object has “worked” so far (that is, no harm has come to you yet), you know that other people do not employ these tactics but don't seem to suffer terrible fates as a result.

• A degree of irrational thinking. While a person who fears needles might avoid hospitals and people known to use intravenous medicines or drugs, a person with an obsessive fear of needles might imagine them everywhere, or go to extreme lengths to avoid all needles, even foregoing lab testing and ignoring medical advice.

• Heightened anxiety. When you can't avoid your feared thing or situation, or at least practice the behavior that makes you feel somewhat safe around it, you suffer emotionally. You might also find yourself tormented by visions of disastrous consequences arising from your actions or lack of same.

• The frequent need for reassurance that your worries are unfounded. (Often, these so-called “reassurances” fail — and can create conflict in close relationships, besides.)

• Disruption of your daily life. For instance, when you make plans, do you always factor in time so you can avoid public bathrooms and run home to use your own? If so, you may have OCD. If you often end up not making plans altogether for fear that you would not be able to practice your avoidance or ritual behavior, again OCD is the likely culprit.