Alcohol flush, but only for the first few sips.

I don’t drink that much or that often, maybe 4-6 drinks on one night per month.

After the first few sips, I get the most ridiculous flush going on. Face is full tomato and sometimes it spreads to my neck.

After about 20 minutes I return to my regular colour and can drink as much as I want.

Any ideas why this happens? I have some Aisan friends so I’m familiar with the Asian flush, but they seem to stay red for the entire time alcohol is in their system so I don’t think it’s that.