OCD is a disease which interferes our "fight Or flight" managing system. It switches on fight Or flight mode on even if there is no danger. It's chemical actions which we can't control but can manage. Best way is to prevent Or postpone ur response (ERP) when u alerted that there's some danger. Bcoz of this we start believing in some unrealistic danger. "Fight Or flight" mode means the response of our body if we Saw a tiger. Our blood starts flowing fastly so that we can run fastly.
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I often think of OCD as a faulty house or car alarm that is set off by the wind blowing on it. The trouble is that we automatically react to it.
After all, even if we all have OCD there is little bit uniqueness in us. We should understand it in the language which works for us. Language which we can understand easily.
That’s exactly how I look at it too. I often get this sense of impending doom for no good reason, it’s just a sense of unease, and I try to tell myself it’s my faulty alarm going off. It usually starts when I’ve been trying to kick the OCD out.
Paediatric ocd and mean dose for sertraline
Answers on OCD and treatment. An extract on mindfulness, easy to read and implement. 
New here & just discovered that I have OCD
OCD worries/anxiety