On Friday, I logged on to Twitter and typed three letters into the search box that have had an important bearing on my life: OCD.

“My OCD is killing me,” one user was saying, beside a snapshot of an office wall where one photo is ever so slightly out of kilter with the others. “Is anyone else OCD about the volume being on even numbers?” queried another.

All the classic OCD stereotypes are here. There are immaculately sharpened pencils and perfectly ordered bookshelves with captions like “my OCD is so happy right now!”, and posts from people disgruntled with co-workers for using their coffee cup because it’s the “only thing I am OCD about”.

Such comical takes on OCD are at best insulting and at worst really damaging to anyone who is genuinely afflicted. As another Mental Health Day comes and goes, perhaps it is time for people to abandon this trivialised take on Obsessive Compulsive Disorder and start facing up to what it really is: a destructive anxiety disorder that latches on to – and then ravages – the things that a sufferer holds the most dear.

OCD is not some quirky disease that is kind of funny. OCD is waking up in the inky blue of the night, in tears, washing and scrubbing your hands until they are red raw through an unrelenting fear of contamination. It is taking hair straighteners to work – tucked there beside your packed lunch – because that’s the only way you can be sure they are definitely unplugged and a deadly fire has been averted. It is checking your door is locked 10, 15, 20 times. It is shutting down your social life and immersing yourself in a never-ending loop: obsession, compulsion, temporary relief.

It is also an illness that often has no immediately obvious outward tells, leaving sufferers alone to deal with an internal bully that won’t permit them a moment’s peace.

I understand that laughter is sometimes the best medicine. All I’m asking is that we stop calling someone “quite OCD” because they never step on the pavement cracks, and start taking the plight of genuine sufferers seriously.

• Yesterday (Wednesday) was World Mental Health Day.