I've a form of OCD, anxiety and panic attacks as well.
I am not afraid of the food being contaminated but I am afraid of using any medication (even paracetamol) or consuming stuff I used to love like caffeine and alcohol. Any substance that might cause even the slightest symptoms, I am afraid will trigger some worse mental problem like schizophrenia or worse anxiety. It's probably irrational to believe that schizophrenia will be triggered like that by...caffeine or alcohol (although anxiety can definitely get worse and I'm afraid I will create another panic attack). But when I am thinking that it might, I get really anxious and as a result I get more physical symptoms for which I worry about intensely thus more physical symptoms, etc, etc -> Panic attack. It's vicious cycle and it's difficult to break out of it.
The worst symptoms are vision problems and dizziness. My vision gets slightly blurred and bright lights look like stars (that's the scariest of the symptoms). I also get dizzy in the same way one might get dizzy if one has done 60 minutes of running. Only I get that when I'm resting. Same with heart pounding although I don't find that as scary for some reason?
Due to sleep deprivation, I also get rare moments during which for literally 1 second I get a dizzy spell (feels like I'm about to fall asleep) and mild nausea (feels like sea sickness). That's ****ing scary as well but it has only happened twice so far and only when I'm really tired and trying to focus intensely on something like reading or driving fast.
In my case, symptoms subside when I refrain from taking any medication or any other substance that might cause any change in my body (cos then I get panicked as hell). Also, and this is a MAJOR one, I feel FAR better if I am not googling stuff. Seriously, that is what has destroyed me. I believe that if I hadn't googled my symptoms 8 years ago, I'd not have had this kind of anxiety now. Also, a good night's sleep is paramount although I wake up 4-5 (perhaps more) times every single night. If I get enough sleep, I feel less stressed even with this kind of constant interruption.
And ofc talking to friends (not always about your illness btw - better to talk about other things to get your mind off it) and aerobic exercise (football and running for me) help too. But in my case, I need to confront my phobias. So I have also started drinking a bit of coffee (less than 100mg of caffeine/day) and try to remind myself of how awesome it was when I was not worried about ****ing caffeine. Alcohol is more difficult 'cos I get REALLY anxious when I get that first buzz. But anyway, I need to expose myself more to my fears 'cos I know that they're not rational (or do I...?)