I've never had problems with antihistamines for my pollen allergies, other than most of them not being 'strong' enough to work.

I went for a hike recently and felt the preliminary symptoms coming on, so I took a phenergan. All good. That night, I had around 5 drinks (G&Tonic) at home before heading out, which is a typically tolerable amount for me. My friends lost me when I ran off. I was later arrested and locked up for my own safety. I don't remember anything except being very angry and violent (which is simply not in my character). I'm told I was jumping fences and running along train tracks. People called the police to come and get me. I'm lucky they did. I barely even remember leaving home.  

My friends and the police were all wondering what I took? When I went back to the police station to apologise later, I don't think the police believed me when I said it was a reaction to mixing antihistamine and alcohol.

I am now battered and bruised from resisting arrest, thrashing about in the cell and god knows what else. I didn't even recognise my own mother. It's a shameful and embarrasing thing. I'm a father.

Alcohol and antihistamines don't mix.