OTC and Rx allergy meds can cause double vision.

How do I know that? From experiance. ....

In early 2014 I was diagnosed with severe food allergies and environmental allergies.(pollen, dust, etc)   I was told by my doc to take off allergy pills, one or combination of few - including zantac (it is histmine h2 blocker) for hearth burn caused by food allergies.  

I was taking a few of them every day.  And I tried to rotate them once in a while to see what works best ...

Now, that I think back - as I started taking them - I started having double vision... First it was not very noticible...but it got worse over time.  Lately it got so bad that I had a problem driving. I often drove with one eye closed... Yea...crazy. 

My gastro thought I need to bevretested for food allergies...see if I got better (we are working on healing my leaky gut - SIBO and Candida.  ) 

So I had to get off all of my allergy meds..for 5 days.  After 3 days I noticed my double vision went away. 

I still have my "normal" astigmatism... 

I had 2 eye docs And when I complained about double vision - they told me I need new glasses with prism. That The glasses should be able to correct It.  . The thought my double vision was a result of myopia and lasic surgery I had in 2000 and cataract surgery I had in 2009...  No one conected me taking daily allergy pills and double vision. 

I am glad I decide to have get tested for allergies. Btw- I still have my normal environmental allergies, but my food allergies are no longer are showing on the skin scratch test... I am not cured - and I need to be careful...

But I no longer need to avoid some foods. (or restaurants) .... 

My food allergies showed app 3-4  years post op RNY...at the same time I was dealing with a lot of gut issues, had a few surgeries... 

It you take one pill - like alleges or zantac- you may get it, if you take 2 or more daily - your changes are more than double...if you take them long term - the incidence of double vision increases... 

Good luck allergy sufferers... I know I need it.